Global Volcanism Program

Klyuchevskoy

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Russia
Eastern Kamchatka Volcanic Arc
Composite | Stratovolcano
2023 CE

Country
Volcanic Region
Landform | Volc Type
Last Known Eruption

56.056°N
160.642°E
4,754 m
15,597 ft
300260

Latitude
Longitude
Summit
Elevation
Volcano
Number

Most Recent Weekly Report: 4 September-10 September 2024 Cite this Report

KVERT lowered the Aviation Color Code for Klyuchevskoy to Green (the lowest level on a four-color scale) at 2300 on 7 September, noting that seismicity had decreased to background levels and no signs of eruptive activity were identified in satellite data. Dates and times are in UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Most Recent Bulletin Report: December 2022 (BGVN 47:12) Cite this Report

Strombolian eruption in November 2022

Klyuchevskoy is one of the most active stratovolcanoes in Russia’s northern Kamchatka Peninsula. After almost three months of inactivity, renewed eruptions in October 2020 included Strombolian activity, explosions, lava flows, and ash plumes (BGVN 45:09). Strong activity continued through January 2021, but then decreased in February, although lava flows, Strombolian activity, and gas-and steam emissions were still present through mid-March (BGVN 46:04). This report covers activity from April 2021 through December 2022, including a short eruption in November, and is based on information provided by the Kamchatkan Volcanic Eruption Response Team (KVERT) and satellite data. During this period, the volcano was inactive until November 2022 when a new eruption phase began.

On several occasions during the reporting period, high winds resuspended unconsolidated ash from the flanks to form plumes (table 18), prompting KVERT to raise the Aviation Color Code (ACC) to Orange (the second highest level on a four-color scale). Each time, the ACC was lowered to Green over the next one to three days, as conditions quieted. These events were not renewed volcanic activity.

Table 19. Dates reported by KVERT during September 2021-September 2022 when high winds resuspended loose ash on Klyuchevskoy’s flanks, prompting an Aviation Color Code increase.

Dates	Plume altitude	Drift
29 Sep 2021	3-5 km	75 km E
25-26 Aug 2022	--	205 km E
04-05 Sep 2022	3-4 km	180 km E
21-23 Sep 2022	3.5-4.5 km	460 km SE

On 17 November 2022 at 2330 local time, an explosive Strombolian eruption began, along with gas-and-steam plumes. A thermal anomaly had been detected starting on 13 November, and intensified when the Strombolian activity began. Lava fountaining at the summit was visible and a thermal anomaly over the summit was identified in satellite images during 17-20 and 24 November. The eruption persisted, and on 20 November (figure 74), KVERT raised the ACC to Yellow (the second lowest level). The eruption continued through at least 26 November and possibly until 5 December. On 1 December, possible ash plumes rose 150 m above the summit. KVERT began to characterize the activity as moderate on 6 December, and on the 22nd KVERT lowered the ACC to Green. On their volcano summary page KVERT listed the eruption dates as 16-26 November 2022.

Figure 74. Image of incandescence above the crater from renewed eruptive activity at Klyuchevskoy on 20 November 2022. Photo by Y. Demyanchuk, courtesy of KVERT.

The MIROVA thermal detection system recorded a few low-power thermal anomalies within 5 km of the summit, some of which included November 2022 eruption period. Sentinel-2 thermal data compiled by MIROVA also showed summit thermal anomalies during the November activity. The HIGP MODVOLC Thermal Alerts System recorded one weak anomaly on 20 November.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/).

Weekly Reports - Index

4 September-10 September 2024 Cite this Report

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 August-3 September 2024 Cite this Report

A sudden increase in seismicity at Klyuchevskoy during 1-3 September prompted KVERT to raise the Aviation Color Code to Yellow (the second lowest level on a four-color scale) at 0822 on 4 September. Dates and times are in UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 December-2 January 2024 Cite this Report

An explosive Strombolian eruption began at Klyuchevskoy on 27 December and a bright thermal anomaly was identified in satellite images. On 30 December an ash plume rose as high as 6 km (19,700 ft) a.s.l. and drifted 195 km NW based on satellite and webcam images. KVERT raised the Aviation Color Code to Orange (the third level on a four-color scale). On 31 December explosions generated ash plumes that rose to 6.5 km (21,300 ft) a.s.l. and drifted 230 km WNW. A thermal anomaly persisted through 1 January, though explosions were not detected; the Aviation Color Code was lowered to Yellow. Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 November-21 November 2023 Cite this Report

KVERT issued a Volcano Observatory Notice for Aviation (VONA) for Klyuchevskoy on 12 November, noting that a plume of resuspended ash rose as high as 6 km (19,700 ft) a.s.l. and drifted more than 60 km E. A thermal anomaly detected in satellite images 14 November was 27 degrees Celsius, cooler than to the 115-degree anomaly detected on 1 November. Fumarolic activity persisted. On 15 November the Aviation Color Code was lowered to Green. On 16 November collapses of hot material in the Apakhonchichsky drainage on the SE flank. Ash plumes from the collapses rose to 5 km (16,400 ft) a.s.l. and drifted 140 km E based on webcam images.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 November-7 November 2023 Cite this Report

An intense eruption at Klyuchevskoy began on 31 October, prompting KVERT to raise the Aviation Color Code to Red (the highest level on a four-color scale). Ash plumes rose as high as 14 km (45,900 ft) a.s.l. and drifted as far as 2,255 km ESE during 31 October-1 November. Lava fountains rose as high has 1 km above the summit and fed lava flows that descended the Apakhonchichsky, Krestovsky, and Kozyrevsky drainages on the SE, S, and W flanks. According to Kamchatka Volcanological Station observers pyroclastic flows descended the flanks. Lahars descended the Studenoy River, blocking the Kozyrevsk-Petropavlovsk federal highway, and descended the Krutenkaya River, blocking the road E of Klyuchi. According to news articles the ash plumes caused some flight cancellations and disruptions in the Aleutians, British Columbia, and along flight paths connecting the Unites States to Japan and South Korea.

Activity began to wane at around 2300 on 1 November and by 2000 on 2 November ash plumes were rising only as high as 6.5 km (21,300 ft) a.s.l. and drifting NNE. The Aviation Color Code was lowered to Orange. The main plume from the most intense phase of the eruption had drifted more than 3,000 km E and SE and contained about 0.1 teragram (100,000 tonnes) of sulfur dioxide based on satellite data. Eruptive activity at the summit continued during 3-4 November, producing ash plumes that rose as high as 5.5 km (18,000 ft) a.s.l. and drifted 125 km ENE. The eruption had ceased by 5 November. Collapses of material and phreatic explosions from hot lava interacting with ice and snow along the Apakhonchichsky drainage generated ash plumes that rose 5.5-8.2 km (18,000-26,900 ft) a.s.l. and drifted almost 260 km E and ENE during 3 and 5-6 November.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station; Simon Carn; NewsBreak; Unalaska Community Broadcasting; CHEK Media

25 October-31 October 2023 Cite this Report

KVERT reported that the Strombolian eruption at Klyuchevskoy continued during 20-29 October and a daily bright thermal anomaly was identified in satellite images. Lava fountains sometimes rose as high as 500 m above the summit and fed lava flows that descended the Apakhonchichsky and Kozyrevsky drainages on the SE and S flanks. Phreatic explosions were sometimes generated from the interaction with lava and glaciers on the flanks and caused collapses of older deposits in the drainages. Plumes of the previously deposited ash generally rose as high as 7 km (23,000 ft) a.s.l. and drifted 280 km NE, E, and SE during 22-29 October, though on 23 and 29 October plumes rose as high as 8 km (26,200 ft) a.s.l. Scientists at the Kamchatka Volcanological Station visited the volcano on 28 October and noted that the cinder cone at the summit had grown. They also observed advancing lava on the E flank that extended about 2 km from the summit to 2,700 m elevation, incandescent material being ejected 500 m above the crater, and avalanches in the Apakhonchichsky drainage. Ash plumes rose more than 2 km.

Activity intensified on 31 October. Ash plumes were identified in satellite images rising as high as 10 km (32,800 ft) a.s.l., prompting KVERT to raise the Aviation Color Code to Red (the highest level on a four-color scale). Ash plumes had drifted as far as 1,300 km SSE. Dates and times are in UTC; specific events are in local time where noted.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

18 October-24 October 2023 Cite this Report

KVERT reported that the Strombolian eruption at Klyuchevskoy continued during 13-20 October and fed lava flows that descended the Apakhonchichsky drainage on the SE flank. Lava descended the Kozyrevsky drainage on 17 October. A daily bright thermal anomaly was identified in satellite images and plumes of resuspended ash rose to 6 km (19,700 ft) a.s.l. and drifted 430 km E. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates and times are in UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 October-17 October 2023 Cite this Report

KVERT reported that the Strombolian eruption at Klyuchevskoy continued during 11-16 October and fed lava flows the descended the Apakhonchichsky drainage on the SE flank. Activity was notable during 11-12 October, characterized by the presence of ash in gas-and-steam plumes and an increase in the lava effusion rate. KVERT raised the Aviation Color Code to Orange (the third level on a four-color scale) as a result. According to observers at the Kamchatka Volcanological Station, lava effusion was almost continuous and incandescent material was ejected as high as 300 m above the crater rim. On 16 October lava on the SE flank melted snow and ice, causing phreatic explosions and large collapses of material from the margins of the flow. Dates and times are in UTC; specific events are in local time where noted.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

4 October-10 October 2023 Cite this Report

KVERT reported that the Strombolian eruption at Klyuchevskoy continued 28 September-11 October. Lava fountaining fed flows that alternately advanced down the Apakhonchichsky and Kozyrevsky drainages on the S and SE flanks. A daily bright thermal anomaly was identified in satellite images; the anomaly was larger during 8-9 October. On 11 October activity increased and gas-and-steam plumes containing a small amount of ash drifted 65 km NE. The Aviation Color Code was raised to Orange (the third level on a four-color scale). Dates and times are in UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 September-3 October 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued 21-28 September. The explosions produced variable amounts of ash. A daily bright thermal anomaly was identified in satellite images. Lava fountaining fed flows that advanced down the Apakhonchichsky and Kozyrevsky drainages on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 September-26 September 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued 14-21 September. A daily bright thermal anomaly was identified in satellite images. Lava fountaining fed flows that advanced down the Kozyrevsky drainage on the SE flank. Plumes of resuspended ash (deposited on the volcano’s N flanks from Sheveluch’s 10-13 April eruption) drifted 50 km E on 22 September, prompting KVERT to raise the Aviation Color Code to Orange (the third level on a four-color scale). The Aviation Color Code was lowered back to Yellow on 24 September; Strombolian activity continued to feed the lava flow. Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 September-19 September 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 7-14 September. A daily bright thermal anomaly was identified in satellite images. Lava fountaining fed flows that advanced down the Apakhonchichsky and Kozyrevsky drainages on the SE flank. Plumes of resuspended ash drifted 550 km E and SE during 9-11 September. The Aviation Color Code remained at Yellow (the second level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 September-12 September 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued 31 August-7 September. A bright thermal anomaly was identified in satellite images every day, except on 7 September due to weather clouds. Lava fountaining fed flows that advanced down the Apakhonchichsky and Kozyrevsky drainages. Plumes of resuspended ash drifted 120 km E during 3-5 September. The Aviation Color Code remained at Yellow (the second level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 August-5 September 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 24-31 August and a daily bright thermal anomaly was identified in satellite images. A plume of ash resuspended by strong winds drifted 95 km E at 3-3.5 km (10,000-11,500 ft) a.s.l., prompting KVERT to raise the Aviation Color Code to Orange (the third level on a four-color scale) at 1240 on 4 September, local time. By 1940 the plume had drifted as far as 170 km E, remining at the same altitudes; the Aviation Color Code was lowered back to Yellow at 1954 (local time). The Aviation Color Code was again raised to Orange for a few hours, during 1532-1808 local time on 5 September, due to plumes of resuspended ash drifting 120 km ENE. KVERT noted that Strombolian activity continued, feeding a lava flow that advanced down the Kozyrevsky drainage on the SW flank. Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 August-29 August 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 17-24 August and a daily bright thermal anomaly was identified in satellite images. Lava advanced down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 August-22 August 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 10-17 August and a daily bright thermal anomaly was identified in satellite images. Lava advanced down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 August-15 August 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 3-10 August and a daily bright thermal anomaly was identified in satellite images. Lava advanced down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 August-8 August 2023 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy continued during 28 July-3 August and a daily bright thermal anomaly was identified in satellite images. Lava advanced down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 July-1 August 2023 Cite this Report

KVERT reported that the Strombolian eruption at Klyuchevskoy continued during 20-27 July and a daily bright thermal anomaly was identified in satellite images. The new lava flow from 19 July continued to advance down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 July-25 July 2023 Cite this Report

KVERT reported that the minor Strombolian eruption at Klyuchevskoy continued during 13-20 July and a daily bright thermal anomaly was identified in satellite images. A new lava flow was first seen on 19 July advancing down the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 July-18 July 2023 Cite this Report

KVERT reported that the minor Strombolian eruption at Klyuchevskoy continued during 6-13 July. A daily thermal anomaly was identified in satellite images. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 July-11 July 2023 Cite this Report

KVERT reported that the minor Strombolian eruption at Klyuchevskoy continued during 29 June-6 July. A daily thermal anomaly was identified in satellite images. Small ash plumes were occasionally observed over the crater during 4-6 July. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 June-4 July 2023 Cite this Report

KVERT reported that a minor Strombolian eruption that began at Klyuchevskoy on 22 June continued through 29 June. A daily thermal anomaly was identified in satellite images. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 June-27 June 2023 Cite this Report

KVERT reported that a minor Strombolian eruption began at Klyuchevskoy at 2323 on 22 June and a bright thermal anomaly was visible in satellite images. The Aviation Color Code was raised to Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 December-27 December 2022 Cite this Report

On 22 December KVERT lowered the Aviation Color Code for Klyuchevskoy to Green (the lowest level on a four-color scale), noting that the eruption had ended in November and the thermal anomaly that had been identified in satellite images had returned to background levels. Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 December-20 December 2022 Cite this Report

KVERT reported that the explosive Strombolian eruption at Klyuchevskoy that began on 16 November had decreased. The Kamchatka Branch of Geophysical Services (KBGS; Russian Academy of Sciences) noted that possible ash plumes rose as high as 150 m above the summit on 1 December. KVERT began to characterize the activity as moderate on 6 December and noted that the periodic thermal anomalies identified in satellite images had become weak on 9 December. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale).

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Institute of Volcanology and Geodynamics, Russian Academy of Natural Science

23 November-29 November 2022 Cite this Report

On 24 November KVERT reported that the Strombolian eruption that had begun at Klyuchevskoy on 16 November was ongoing. Lava fountaining at the summit was visible and a thermal anomaly over the summit was identified in satellite images during 17-20 and 24 November. The Aviation Color Code remained at Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 November-22 November 2022 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was first identified on 13 November and was visible daily through 20 November. An explosive Strombolian eruption began at 2330 local time on 17 November, the same day that the thermal anomaly intensified. Gas-and-steam plumes drifted SE. The Strombolian eruption and gas emissions persisted; KVERT raised the Aviation Color Code to Yellow (the second lowest level on a four-color scale) on 20 November.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 September-27 September 2022 Cite this Report

Strong winds re-suspended ash from the E flank of Klyuchevskoy and created plumes that were visible in satellite images drifting 460 km SE during 21-22 September. KVERT raised the Aviation Color Code to Orange on 21 September but lowered it back to Green on 24 September. Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 August-6 September 2022 Cite this Report

Strong winds re-suspended ash from the E flank of Klyuchevskoy and created plumes that were visible in satellite and webcam images drifting 180 km E on 5 September, local time. The plumes rose to altitudes of 3-4 km (9,800-13,100 ft) a.s.l. KVERT raised the Aviation Color Code to Orange but lowered it back to Green the next day.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 August-30 August 2022 Cite this Report

Strong winds re-suspended ash from the E flank of Klyuchevskoy and created plumes that were visible in satellite images drifting more than 205 km E during 25-26 August. KVERT raised the Aviation Color Code to Orange on 26 August; plumes were not visible the next day so the Aviation Color Code was lowered back to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 September-5 October 2021 Cite this Report

On 29 September strong winds resuspended unconsolidated ash from Klyuchevskoy’s flanks causing KVERT to raise the Aviation Color Code to Orange (the second highest level on a four-color scale). Conditions were quiet the next day; KVERT lowered the Aviation Color Code back to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 September-28 September 2021 Cite this Report

KVERT reported that on 29 September high winds caused unconsolidated ash from Klyuchevskoy’s flanks to form plumes that rose to 3-5 km (9,800-16,400 ft) a.s.l. and drifted 75 km E. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 March-30 March 2021 Cite this Report

KVERT reported that the flank eruption on Klyuchevskoy’s lower NW flank had ended on 20 March. Weak incandescence from the cinder cone and lava flows visible in webcam images reflected cooling. The temperature of the thermal anomaly identified in satellite data continued to decrease. On 24 March the Aviation Color Code was lowered to Green (the lowest level). According to satellite data, a plume of resuspended ash extended for 72 km E of the volcano on 25 March; no eruption was reported. On 25 March the Aviation Color Code was briefly increased to Orange (the second highest level on a four-color scale) and was lowered to Green by 26 March.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 March-23 March 2021 Cite this Report

KVERT reported that the Strombolian eruption from vents on Klyuchevskoy’s lower NW flank continued during 12-19 March. A large, bright thermal anomaly over the vents was identified in satellite images. Kamchatka Volcanological Station scientists visited the eruption site on 16 March and observed decreased activity. A small lava flow effused from a vent at the W base of the cone and lava flowed from the N side. Every few seconds material was ejected as high as 100 m above the cone’s rim. On 22 March the cinder cone was weakly incandescent and lava effusion continued to be observed in webcam images. The temperature of the thermal anomaly identified in satellite data also significantly decreased. The Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale) on 22 March. Two days later, on 24 March, the Aviation Color Code was lowered to Green (the lowest level); weak incandescence from the cone and flows visible in webcam images reflected cooling.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

10 March-16 March 2021 Cite this Report

KVERT reported that the Strombolian eruption from vents on Klyuchevskoy’s lower NW flank continued during 5-12 March. A large, bright thermal anomaly over the vents was identified daily in satellite images. A plume of re-suspended ash drifted 375 km E on 5 March. IVS FEB RAS posted that the lava traveled downslope, melting ice and snow on the Erman glacier; the meltwater formed mud flows along the along the Krutenkaya River. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

3 March-9 March 2021 Cite this Report

KVERT reported that the eruption from vents on Klyuchevskoy’s lower NW flank continued during 26 February-5 March. A large, bright thermal anomaly over the vents was identified daily in satellite images. IVS FEB RAS volcanologists visited the field site on 2 March during good weather conditions. They estimated that the cinder cone was 54 m high and 101 m wide at the base. Lava effused from the cone and traveled downslope, melting ice and snow that formed muddy streams. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

24 February-2 March 2021 Cite this Report

KVERT reported that the eruption at two vents on Klyuchevskoy’s lower NW flank continued during 24-26 February. Both vents produced lava flows and ejected lava 50 m high. A cinder cone had formed over the higher vent. A bright thermal anomaly over the vents was identified in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

17 February-23 February 2021 Cite this Report

KVERT reported that during 1100-1150 on 18 February a new vent opened on Klyuchevskoy’s lower NW flank, near Erman glacier at elevations of 2,500-2,700 m, based on satellite images. Snowfall in the area of Klyuchi during 18-19 February inhibited webcam views. Bright incandescence was visible in webcam images beginning at 0323 on 21 February, likely indicating an advancing lava flow. On 23 February the Kamchatka Volcanological Station team reported that lava was flowing from two vents and bombs were being ejected 50 m high. A lahar along the Krutenkaya River was visible in an area 7 km E of Klyuchi Village (30 km NNE). Bright incandescence over the two flank vents was identified in satellite and video images on 24 February. KVERT raised the Aviation Color Code to Orange (the second highest level on a four-color scale).

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

10 February-16 February 2021 Cite this Report

KVERT reported that activity at Klyuchevskoy notably decreased, with the eruption likely ending on 8 February. The temperature of the thermal anomaly identified in satellite images abruptly dropped on 7 February, and the magnitude of volcanic tremor decreased during 7-8 February and continued to decline through 12 February. Strombolian activity was not visible at night during 11-12 February. The Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale) on 12 February.

The Tokyo VAAC reported that re-suspended ash was identified in satellite images during 12-13 February. On 15 February an ash plume rose to 5.2 km (17,000 ft) a.s.l. and drifted NE.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

3 February-9 February 2021 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 29 January-5 February and lava advanced down the Apakhonchich drainage on the SE flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 92 km in multiple directions. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 January-2 February 2021 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 22-29 January and lava advanced down the Kozyrevsky drainage on the S flank and the Apakhonchich drainage on the SE flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 125 km in multiple directions. On 24 January collapses from the lava flow sent large amounts of material and pyroclastic flows down the Apakhonchich drainage. An ash cloud rose to 9.6 km (31,500 ft) a.s.l. and drifted 60 km N then NE. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 January-26 January 2021 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 15-22 January and lava advanced down the Kozyrevsky drainage on the S flank and the Apakhonchich drainage on the SE flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 200 km in multiple directions. A notable eruptive event on 18 January generated an ash plume that rose as high as 7.5 km (24,600 ft) a.s.l. and drifted 500 km W. Ashfall (1 cm thick) was reported in Kozyrevsk. On 24 January collapses from the lava flow at about 2,200 elevation sent large amounts of material and pyroclastic flows down the Apakhonchich drainage. KVERT estimated that the ash plumes from the event rose to 8.5 km (27,900 ft) a.s.l. The Tokyo VAAC stated that ash plumes rose as high as 10.4 km (34,000 ft) a.s.l. and drifted W on the same day. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 January-19 January 2021 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 8-15 January and lava advanced down the Kozyrevsky drainage on the S flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 90 km in multiple directions. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 January-12 January 2021 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 1-8 January and lava advanced down the Kozyrevsky drainage on the S flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 70 km in multiple directions. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 December-5 January 2021 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 25 December-1 January and lava advanced down the Kozyrevsky drainage on the S flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 250 km in multiple directions. Kamchatka Volcanological Station observers reported that at about 1720 on 2 January a landslide descended the Apakhonchich drainage on the SE flank, producing a cloud of ash that rose about 1 km and quickly drifted SE. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 December-29 December 2020 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 18-25 December and lava advanced down the Kozyrevsky drainage on the S flank. Lava first flowed down the S flank on 8 December. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 340 km mainly E. The Kamchatka Volcanological Station field team visited the area on 24 December to do work on field stations. They observed explosions that ejected incandescent material 300 m above the crater rim. A growing cinder cone in the summit crater was about 75 m higher than part of the crater rim. The lava flow ended at about 3,700 m elevation and spalled off incandescent material, descending an additional 350 m. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatka Volcanological Station

16 December-22 December 2020 Cite this Report

KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 11-18 December and lava advanced down the Kozyrevsky drainage on the S flank. A large bright thermal anomaly was identified daily in satellite images. A steam-and-gas plume with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 120 km NE on 13 December. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 December-15 December 2020 Cite this Report

KVERT reported that Strombolian and Vulcanian activity at Klyuchevskoy continued during 4-7 December and lava advanced down the Kozyrevsky drainage on the S flank. A large bright thermal anomaly was identified daily in satellite images. Steam-and-gas plumes with some ash rose to 7 km (23,000 ft) a.s.l. and drifted 130 km NW and NE. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 December-8 December 2020 Cite this Report

KVERT reported that Strombolian and Vulcanian activity at Klyuchevskoy continued during 27 November-4 December and lava advanced down the Apakhonchich drainage on the SE flank. A large, bright thermal anomaly was identified daily in satellite images. During 20-21 and 23-26 November steam-and-gas plumes with some ash rose to 7 km (23,000 ft) a.s.l. and drifted 300 km NW and E. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 November-1 December 2020 Cite this Report

KVERT reported that Strombolian and Vulcanian activity at Klyuchevskoy continued during 20-27 November and lava advanced down the Apakhonchich drainage on the SE flank. A large bright thermal anomaly was identified daily in satellite images. During 20-21 and 23-26 November ash plumes drifted 186 km N, E, and SE. The Aviation Color Code remined at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 November-24 November 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy continued during 13-20 November and lava advanced down the Apakhonchich drainage on the SE flank. A large, bright thermal anomaly was identified daily in satellite images. During 16-18 November explosions recorded in satellite and video data produced ash plumes that rose as high as 7.5 km (24,600 ft) a.s.l. and drifted 104 km E, SE, and S. The Aviation Color Code remained at Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 November-17 November 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy continued during 6-13 November and lava advanced down the Apakhonchich drainage on the SE flank. Gas-and-steam emissions contained some ash and during 7-9 November drifted 85 km E. A large bright thermal anomaly was identified daily in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 November-10 November 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy continued during 30 October-6 November and lava advanced down the Apakhonchich drainage on the SE flank. Gas-and-steam emissions contained some ash. A large bright thermal anomaly was identified daily in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 October-3 November 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy continued during 23-30 October and lava advanced down the Apakhonchich drainage on the SE flank. Gas-and-steam emissions contained some ash. A large, bright thermal anomaly was identified daily in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 October-27 October 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy continued during 16-23 October and lava advanced down the Apakhonchich drainage on the SE flank. A large bright thermal anomaly was identified daily in satellite images and on 18 October an ash plume drifted 90 km E. The Aviation Color Code remained at Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 October-20 October 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was continuing during 9-16 October and a lava flow was advancing down the Apakhonchich drainage on the SE flank. A large bright thermal anomaly was identified in satellite images and during 8-9 October ash plumes drifted 270 km SE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 October-13 October 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was continuing and a lava flow was advancing down the Apakhonchich drainage on the SE flank. Activity increased during 7-8 October and was characterized by strong explosions, collapses of parts of the drainage sides, strong thermal anomalies, and ash plumes that drifted over 200 km SE. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale) on 8 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 September-6 October 2020 Cite this Report

Strombolian activity at Klyuchevskoy began at 1003 on 2 October prompting KVERT to raise the Aviation Color Code to Yellow (the second lowest level on a four-color scale). Explosions ejected ash 300-400 m above the volcano and produced gas-and-steam plumes with some ash that drifted down the E flank.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 July-14 July 2020 Cite this Report

KVERT reported that the temperature of the thermal anomaly at Klyuchevskoy sharply decreased on 3 July, possibly signaling the end of the current Strombolian phase. During 4-14 July the anomaly continued to decline and only weak fumarolic activity was visible. The Alert Level was lowered to Yellow (the second lowest level on a four-color scale) on 14 July.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 July-7 July 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 26 June-3 July along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Avalanches of material on the S side of the lava flow were sometimes visible. Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 June-30 June 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 19-26 June along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Avalanches of material on the S side of the lava flow were sometimes visible. Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 June-23 June 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 12-19 June along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Avalanches of material on the S side of the lava flow were sometimes visible. Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 June-16 June 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 5-12 June along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Gas-and-steam plumes with some ash drifted 40 km W and E on during 6-7, 9, and 11 June. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 June-9 June 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 29 May-5 June along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Gas-and-steam plumes with some ash drifted 465 km SE and E on 29 and 31 May, and 1 June. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 May-2 June 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 22-29 May along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Gas-and-steam plumes with some ash drifted over 200 km E during 22 and 25-28 May. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 May-26 May 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 15-22 May along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Gas-and-steam plumes with some ash drifted 100 km NW, E, and SE during 15-17 and 21 May. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 May-19 May 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 8-15 May along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. Vulcanian activity on 8, 10, and 13 May produced ash plume that drifted 145 km SE and E. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 May-12 May 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 1-8 May along with a bright thermal anomaly identified in satellite images. A lava flow continued to advance down the Apakhonchich drainage on the SE flank. An ash plume drifted 22 km SE on 2 May. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 April-5 May 2020 Cite this Report

KVERT reported that Strombolian and Vulcanian activity at Klyuchevskoy was visible during 24 April-1 May along with a bright thermal anomaly identified in satellite images. Ash plumes drifted about 425 km W, and a lava flow continued to descend the Apakhonchich drainage on the SE flank. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 April-28 April 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 17-24 April along with a bright thermal anomaly identified in satellite images. Gas-and-steam plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 470 km E. A lava flow began to descend the SE flank in the Apakhonchich drainage at 0607 on 19 April. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 April-21 April 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 10-17 April along with a bright thermal anomaly identified in satellite images. Gas-and-steam plumes with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 200 km S and E on those same days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 April-14 April 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 3-10 April along with a bright thermal anomaly identified in satellite images. Vulcanian activity was visible during 6-9 April; ash plumes drifted 200 km S, SE, and E at altitudes of 5.5-6 km (18,000-19,700 ft) a.s.l. on those same days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 April-7 April 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 27 March-3 April, and a bright thermal anomaly was identified in satellite images those same days except for 1 April. Vulcanian activity was visible during 29-20 March; ash plumes drifted as far as 455 km E and NE at altitudes of 5.5-6 km (18,000-19,700 ft) a.s.l. on those same days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 March-31 March 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 20-27 March, and a bright thermal anomaly was identified in satellite images those same days. Vulcanian activity was visible on 20 and 25 March; ash plumes drifted as far as 180 km E and NE at altitudes of 5.5-6 km (18,000-19,700 ft) a.s.l. on those same days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 March-24 March 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 13-20 March, and the number of hot avalanches descending all of the flanks continued to increase. A bright thermal anomaly was identified daily in satellite images. Gas-and-steam plumes containing some ash drifted as far as 170 km E, NE, and N at altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l. during 15 and 18-19 March. Vulcanian activity was visible on 19 March. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 March-17 March 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 6-13 March, and the number of hot avalanches descending the flanks in all directions significantly increased. A bright thermal anomaly was identified daily in satellite images, and gas-and-steam plume containing some ash drifted 135 km E, NE, and N during 8-9 and 12 March. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 March-10 March 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 28 February-6 March, and a bright thermal anomaly was identified in satellite images those same days. A gas-and-steam plume containing some ash drifted 60 km WNW on 2 March. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 February-3 March 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 21-28 February, and a strong thermal anomaly was identified in satellite images those same days. A gas-and-steam plume containing some ash drifted 120 km E on 23 February. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 February-25 February 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 14-21 February, and a thermal anomaly was identified in satellite images those same days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 February-18 February 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 7-14 February, and a thermal anomaly was identified in satellite images those same days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 February-11 February 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 31 January-7 February, and a thermal anomaly was identified those same days in satellite images. Vulcanian activity was recorded on 31 January and 4 February; explosions generated ash plumes that rose to 5.5 km (18,000 ft) a.s.l. and drifted 145 km E. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 January-4 February 2020 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 24-31 January, and a thermal anomaly was identified in satellite images during 27-28 and 30 January. Vulcanian activity was recorded on 30 January; explosions generated ash plumes that rose to 5.5 km (18,000 ft) a.s.l. and drifted 282 km E. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 January-28 January 2020 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 17-24 January. Strombolian activity was visible daily, and Vulcanian activity was evident on 22 January. Explosions produced ash plumes that rose 5-6 km (16,400-19,700 ft) a.s.l.; an ash plume drifted 460 km E on 22 January. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 January-21 January 2020 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 10-12 and 15-16 January. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 January-14 January 2020 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 3-10 January. Strombolian activity was visible all week and Vulcanian explosions were noted on 6 January. Ash plumes drifted 55 km ENE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 January-7 January 2020 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 28-30 December and 2 January, and ash plumes drifted 150 km SE during 29-30 December. Strombolian and Vulcanian activity were observed during 29-31 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 December-31 December 2019 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy and a weak thermal anomaly identified in satellite images were recorded each day during 17-27 December. A gas-and-steam plume drifted 16 km NE on 22 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 December-24 December 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 12-15 and 17 December, and Strombolian activity was visible during 13-15 and 17 December. Gas-and-steam plumes rose to 5-5.5 km (16,400-18,000 ft) a.s.l. and drifted 45 km NE on 14 and 19 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 December-17 December 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 5, 7, and 11-12 December, and Strombolian activity was visible during 11-12 December. An ash plume rose to 4.5 km (14,800 ft) a.s.l. and drifted 30 km SE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 December-10 December 2019 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible on 29 November and 1 December, the same days a weak thermal anomaly was identified in satellite images. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 November-3 December 2019 Cite this Report

KVERT reported that Strombolian activity at Klyuchevskoy was visible during 21 and 26-27 November, and a weak thermal anomaly was identified in satellite images during 21-25 and 28 November. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 November-26 November 2019 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images on 14 November. Strombolian activity and a series of ash explosions were visible on 20 November. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 November-19 November 2019 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 8 and 10-13 November. Strong crater incandescence was visible at night during 10-11 November. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 November-12 November 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images on 6 November. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 October-5 November 2019 Cite this Report

KVERT reported that ash plumes and steam-and-gas plumes with some ash drifted 130 km SW on 25 October according to video and satellite data. A weak thermal anomaly was identified in satellite images during 26-27 and 30 October. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 October-29 October 2019 Cite this Report

A small amount of ash began to be visible in gas-and-steam emissions at Klyuchevskoy beginning at 1020 on 24 October, prompting KVERT to raise the Aviation Color Code to Yellow (the second lowest level on a four-color scale). Later that day video images showed an ash plume rising as high as 6 km (19,700 ft) a.s.l. and drifting 40 km NE. The Aviation Color Code was raised to Orange. KVERT and the Tokyo VAAC noted that during 25-28 October ash plumes rose to 5.5 km (18,000 ft) a.sl. and drifted 15-20 km SE, E, and NW. A weak thermal anomaly over the volcano was identified on 18 and 24 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 September-24 September 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was sometimes visible in satellite images, though the temperature of the anomaly had steadily decreased over time. Gas-and-steam emissions persisted; ash was last emitted on 2 July. The Aviation Color Code was lowered to Green (the lowest on a four-color scale) on 24 September.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 August-3 September 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was sometimes visible in satellite images and that gas-and-steam emissions continued, though ash was last emitted on 2 July. The Aviation Color Code was lowered to Yellow (the second highest lowest on a four-color scale) on 30 August.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 August-27 August 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 17-23 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 August-20 August 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 13-14 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 August-13 August 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 5-6 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 July-6 August 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 26, 29, and 31 July, and 1 August. An ash emission was visible in webcam images on 1 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 July-30 July 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 18-19 July. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 July-23 July 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images on 15 July. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 July-16 July 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 4-5 and 7 July. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 July-9 July 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images during 1-3 July, and ash plumes drifted as far as 85 km E and SE during 1-2 July. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 June-2 July 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images on 23 and 26 June, and a gas-and-steam plume with some ash content drifted E on 26 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 June-25 June 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible in satellite images on 14 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 June-18 June 2019 Cite this Report

KVERT reported that a weak thermal anomaly at Klyuchevskoy was visible in satellite images during 11-13 June. Explosions during 11-12 June were recorded in video and satellite data generating ash plumes that rose to 5.5-6 km (18,000-19,700 ft) a.s.l. and drifted 200 km WNW. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 June-11 June 2019 Cite this Report

On 12 June ash plumes from Klyuchevskoy rose to an altitude of 5 km (16,400 ft) a.s.l. and drifted 10 km N, prompting KVERT to raise the Aviation Color Code to Orange (the second highest level on a four-color scale). Ash emissions continued later that day with plumes rising to 5 km a.s.l. and drifting 68 km WNW.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 May-4 June 2019 Cite this Report

KVERT reported that ash plumes from Klyuchevskoy were last observed on 22 April and a weak thermal anomaly was last identified on 15 May. KVERT lowered the Aviation Color Code to Yellow (the second lowest level on a four-color scale) on 31 May.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 May-28 May 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images on 17, 19, and 21 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 May-21 May 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images on 10 and 15 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 May-14 May 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 6 and 8-9 May. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 May-7 May 2019 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 26 April-3 May. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 April-30 April 2019 Cite this Report

KVERT reported that during 21-22 April a weak thermal anomaly over Klyuchevskoy was identified in satellite images along with gas-and-steam plumes containing ash drifting 160 km E. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 April-23 April 2019 Cite this Report

KVERT reported that at 0921 and 1155 on 22 April ash plumes from Klyuchevskoy rose to altitudes of 5-5.5 km (16,400-18,000 ft) a.s.l. and drifted 130-140 km E, based on satellite and webcam data. KVERT noted that the ash content in the plumes had significantly increased compared to emissions first observed on 9 April. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 April-9 April 2019 Cite this Report

KVERT reported that at 1030 on 9 April a small ash plume from Klyuchevskoy was identified in satellite images rising to altitudes of 3-3.5 km (10,000-11,500 ft) a.s.l. and drifting 20 km SW. The Aviation Color Code was raised to Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 September-18 September 2018 Cite this Report

On 12 September KVERT reported that activity at Klyuchevskoy had continued to decrease. A weak thermal anomaly was occasionally visible though the temperature of the anomaly had steadily decreased. Gas-and-steam emissions continued. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 June-3 July 2018 Cite this Report

On 29 June KVERT reported that activity at Klyuchevskoy had decreased, with the last ash plume visible on 15 June. Gas-and-steam emissions continued. The Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 June-26 June 2018 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 16-17 and 19 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 June-19 June 2018 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 13-14 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 June-12 June 2018 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy and a diffuse ash plume drifting 12 km W were identified in satellite images on 6 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 May-5 June 2018 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images on 25 and 28 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 May-29 May 2018 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 19-20 and 24 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 May-22 May 2018 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 13-14 May. Strong explosions began at 0315 on 15 May, and generated ash plumes that rose as high as 10.5 km (34,400 ft) a.s.l. The ash clouds lingered around Klyuchevskoy and surrounding volcanoes for about eight hours before gradually dissipating. Nighttime summit incandescence and a hot avalanche were noted. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 May-8 May 2018 Cite this Report

Based on webcam and satellite observations KVERT reported that at 1150 on 8 May an ash plume from Klyuchevskoy rose to altitudes of 5-5.5 km (16,400-18,000 ft) a.s.l. and drifted 105 km SSE. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 February-20 February 2018 Cite this Report

Based on information from the Yelizovo Airport (UHPP) and satellite images, the Tokyo VAAC reported that on 18 February an ash plume from Klyuchevskoy rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)

17 January-23 January 2018 Cite this Report

Based on satellite observations KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible during 11-12, 15, and 17 January. Gas-and-steam plumes containing some ash drifted about 120 km W and E during 12 and 17-18 January. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 January-16 January 2018 Cite this Report

Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 160 km NW and E during 5-6 and 8-10 January. A weak thermal anomaly was visible on 6 and 8 January. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 January-9 January 2018 Cite this Report

Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 150 km in multiple directions during 1 and 3-4 January. A weak thermal anomaly was visible on 3 January. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 December-2 January 2018 Cite this Report

Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 220 km E during 22-25 December. A weak thermal anomaly was visible on 22 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 December-26 December 2017 Cite this Report

Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 140 km E during 16-19 December. A weak thermal anomaly was visible on 16 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 December-19 December 2017 Cite this Report

Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 95 km E and SW on 7 and 13 December, respectively. A weak thermal anomaly was visible on 11 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 December-12 December 2017 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 5-6 December. Ash plumes rose as high as 5.5 km (18,000 ft) a.s.l. and drifted about 180 km during 5-8 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 November-5 December 2017 Cite this Report

KVERT reported that strong gas-and-steam emissions at Klyuchevskoy were recorded by a webcam during 2-5 December, and contained some ash starting at 2300 on 5 December. The gas-and-ash plumes were visible in satellite data drifting 170 km E. KVERT raised the Aviation Color Code to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 September-26 September 2017 Cite this Report

KVERT reported that during 16-17 September a weak thermal anomaly at Klyuchevskoy was identified in satellite images. KVERT noted that the last time ash was emitted from the volcano was on 7 September; the Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 September-19 September 2017 Cite this Report

KVERT reported that on 8 September a weak thermal anomaly at Klyuchevskoy was identified in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 September-12 September 2017 Cite this Report

KVERT reported that on 7 September explosions at Klyuchevskoy recorded by a webcam generated ash plumes that rose as high as 6 km (19,700 ft) a.s.l. and drifted about 50 km NE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 August-5 September 2017 Cite this Report

Based on satellite data, KVERT reported that ash plumes from explosions at Klyuchevskoy rose 6 km (19,700 ft) a.s.l. and drifted 550 km in multiple directions during 24-25 and 30 August. On 6 September KVERT noted that activity had decreased and that there was snow on the flanks; ash emissions were last observed on 30 August. The Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 August-29 August 2017 Cite this Report

KVERT reported that on 19 August explosions at Klyuchevskoy generated ash plumes that rose 6-7 km (19,700-23,000 ft) a.s.l.; the plumes drifted 140 km NW initially, and then 270 km SW and 90 km NE. Ash plumes during 20-25 August drifted as far as 560 km NW, W, and SW. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 August-22 August 2017 Cite this Report

KVERT reported that ash plumes from Klyuchevskoy were identified in satellite images drifting 315 km E and NW during 11-12 and 15-17 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 August-15 August 2017 Cite this Report

KVERT reported that ash plumes from Klyuchevskoy were identified in satellite images drifting 300 km SW, SE, and NE during 4 and 7-11 August. A thermal anomaly was identified on 4 and 7 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 August-8 August 2017 Cite this Report

KVERT reported that ash plumes from Klyuchevskoy were identified in satellite images drifting 65 km SW on 2 August and 250 km ESE on 3 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 July-1 August 2017 Cite this Report

KVERT reported that during 22-27 July ash plumes from Klyuchevskoy were identified in satellite images drifting 120 km E and NE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 July-25 July 2017 Cite this Report

KVERT reported that during 19-20 July a weak thermal anomaly over Klyuchevskoy was identified in satellite images, and ash plumes drifted 300 km SW, SE, E, and NE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 July-18 July 2017 Cite this Report

KVERT reported that during 8 and 12-13 July explosions at Klyuchevskoy generated ash plumes that rose as high as 5 km (16,400 ft) a.s.l. and drifted about 50 km SE. A weak thermal anomaly was identified in satellite images during 10-12 July. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 July-11 July 2017 Cite this Report

KVERT reported that during 1-2 and 5-6 July a weak thermal anomaly was identified in satellite images at Klyuchevskoy. Explosions during 1-2 and 5-6 July generated ash plumes that rose as high as 5 km (16,400 ft) a.s.l. and drifted 160 km SE, S, and SW. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 June-4 July 2017 Cite this Report

KVERT reported that during 22-24 and 27-28 June a weak thermal anomaly was identified in satellite images at Klyuchevskoy. Explosions on 24 and 26 June generated ash plumes that rose to 5-6 km (16,400-19,700 ft) a.s.l. and drifted 112 km S and SE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 June-27 June 2017 Cite this Report

KVERT reported that during 16-17 June a weak thermal anomaly was identified in satellite images at Klyuchevskoy. Explosions generated ash plumes that rose to 6-7 km (19,700-23,000 ft) a.s.l. and drifted about 300 km E and W during 16-17 and 22 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 June-20 June 2017 Cite this Report

KVERT reported that during 9-16 June explosions at Klyuchevskoy generated ash plumes that rose to 6-7 km (19,700-23,000 ft) a.s.l. and drifted about 580 km SE and SW. A weak thermal anomaly was identified in satellite images during 11-16 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 June-13 June 2017 Cite this Report

KVERT reported that during 2-9 June explosions at Klyuchevskoy generated ash plumes that rose to 5 km (16,400 ft) a.s.l. and drifted about 325 km NE, SE, and SW. A weak thermal anomaly was identified in satellite images on 4 and 8 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 May-6 June 2017 Cite this Report

KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 27 and 30-31 May and 2 June. Explosions during 1-2 June generated ash plumes that rose to 6 km (19,700 ft) a.s.l. and drifted about 400 km SSE. Ash plumes drifted over Petropavlovsk-Kamchatsky and Elizovo. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 May-30 May 2017 Cite this Report

KVERT reported that a weak thermal anomaly was identified in satellite images over Klyuchevskoy on 22 and 25 May; weather clouds often obscured views of the volcano. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 May-23 May 2017 Cite this Report

Based on video and satellite data, KVERT reported that explosions at Klyuchevskoy on 17 May generated ash plumes that rose to 6 km (19,700 ft) a.s.l. and drifted about 180 km N and NE. A weak thermal anomaly was identified daily. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 May-16 May 2017 Cite this Report

KVERT reported that ash plumes from Klyuchevskoy were identified in satellite images drifting 270 km SE and NW during 5-6 and 10-11 May, respectively. A weak thermal anomaly was noted on 5 and 10 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 May-9 May 2017 Cite this Report

KVERT reported that a weak thermal anomaly was identified in satellite images over Klyuchevskoy during 30 April-1 May, and an ash plume drifted about 52 km E on 1 May. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 April-2 May 2017 Cite this Report

KVERT reported that a weak thermal anomaly was identified in satellite images over Klyuchevskoy daily during 21-28 April. Ash plumes drifted about 125 km SW during 22-23 and 25 April. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 April-25 April 2017 Cite this Report

KVERT reported that a weak thermal anomaly was detected over Klyuchevskoy during 14-17 and 23 April. A steam-and-gas plume that rose to 5 km (16,400 ft) a.s.l. and drifted 125 km SW on 23 April contained some ash, prompting KVERT to raise the Aviation Color Code to Orange. On 24 April satellite images showed an ash plume drifting 72 km SW at an altitude of 7 km (23,000 ft) a.s.l. On 25 April KVERT noted that activity had significantly decreased and only steam-and-gas emissions were observed. The Aviation Color Code was lowered to Yellow. On 25 April ash was again present in a plume; KVERT raised the Aviation Color Code to Orange. The plume rose 3-4 km (9,800-13,100 ft) a.s.l. and drifted 60 km SW.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 April-11 April 2017 Cite this Report

KVERT reported that during 1-4 April explosions at Klyuchevskoy generated ash plumes that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. Satellite images showed a thermal anomaly over the volcano during 1-2 and 4 April, and ash plumes that drifted 400 km in multiple directions. No explosions were recorded after 4 April; the Aviation Color Code was lowered to Yellow on 10 April.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 March-4 April 2017 Cite this Report

KVERT reported that during 27-30 March explosions at Klyuchevskoy generated ash plumes that rose to an altitude of 7 km (23,000 ft) a.s.l. Satellite images showed a thermal anomaly over the volcano during the previous week, and ash plumes that drifted 300 km in multiple directions. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 March-28 March 2017 Cite this Report

On 24 March KVERT reported that gas-and-steam emissions continued to rise from Klyuchevskoy's crater, and a weak thermal anomaly was occasionally identified in satellite images. The Aviation Color Code was lowered to Green (the lowest level on a four-color scale). On 28 March a gas, steam, and ash plume identified in satellite data rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted 108 km ENE. The Aviation Color Code was raised to Yellow. The next day an ash plume rose as high as 7.5 km (24,600 ft) a.s.l. and drifted 75 km SW. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 March-21 March 2017 Cite this Report

On 16 March KVERT reported that although gas-and-steam emissions continued to rise from Klyuchevskoy's crater, and a weak thermal anomaly was identified in satellite images, no explosions had been detected since 8 March. The Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 March-14 March 2017 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite data during 2-3, 5, and 8-9 March. Explosions on 8 March produced ash plumes that rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted about 20 km NW. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 March-7 March 2017 Cite this Report

KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite data during 25 February and 1-2 March. At 1340 on 2 March a gas, steam, and ash plume recorded by the webcam rose to altitudes of 8-9 km (26,000-30,000 ft) a.s.l. and drifted 110 km NE and NW. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 January-24 January 2017 Cite this Report

KVERT reported that during 13-20 January gas-and-steam emissions from Klyuchevskoy sometimes contained minor amounts of ash. Satellite images showed a daily thermal anomaly over the volcano. On 22 January an ash plume rose to altitudes of 5-5.5 km (16,400-18,000 ft) a.s.l. and drifted 45 km E. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale), but was again lowered to Yellow on 24 January.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 January-17 January 2017 Cite this Report

KVERT reported that during 6-13 January gas-and-steam emissions from Klyuchevskoy sometimes contained minor amounts of ash. Satellite images showed a daily thermal anomaly over the volcano and ash plumes that drifted 160 km ESE during 9-10 January. The Aviation Color Code was lowered to Yellow (the second lowest level on a four-color scale) on 16 January.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 January-10 January 2017 Cite this Report

KVERT reported that during 2-6 January daily satellite images showed a thermal anomaly over Klyuchevskoy. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 December-3 January 2017 Cite this Report

Based on satellite and webcam images KVERT reported that explosions at Klyuchevskoy recorded on 1 January generated ash plumes that rose to an altitude of 5 km (16,400 ft) a.s.l. and drifted 114 km SE. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 December-27 December 2016 Cite this Report

On 26 December KVERT reported that a weak thermal anomaly over Klyuchevskoy had been detected after the April-November eruption. Gas-and-steam plumes sometimes contained small amounts of ash. The Aviation Color Code was raised to Yellow (the second lowest on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 November-29 November 2016 Cite this Report

KVERT reported that a daily thermal anomaly over Klyuchevskoy was visible in satellite images during 18-25 November. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 November-22 November 2016 Cite this Report

KVERT reported that on 17 November an ash plume from Klyuchevskoy visible in satellite images rose to an altitude of 5 km (16,400 ft) a.s.l. and drifted almost 60 km WNW. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 November-15 November 2016 Cite this Report

On 8 November, KVERT reported that activity at Klyuchevskoy had decreased significantly and therefore the Aviation Color Code was lowered to Yellow. Lava effusion onto the flanks was last noted on 3 November; the next day the thermal anomaly was reduced. Ash plumes were last detected in satellite images during 3-4 November. Strombolian activity in the crater was also observed on those days. Strong gas-and-steam emissions continued.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 November-8 November 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 28 October-4 November. Gas-and-steam emissions with variable amounts of ash rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano. Gas, steam, and ash plumes from explosions rose to altitudes of 5-8 km (16,400-26,200 ft) a.s.l. and drifted 277 km E and SE during 30-31 October and 1-3 November. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 October-1 November 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 21-28 October. Gas-and-steam emissions with variable amounts of ash rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano, and ash plumes from explosions that rose to altitudes of 5-7 km (16,400-23,000 ft) a.s.l. and drifted 335 km E, N, NW, and W during 20-21 and 23-27 October. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 October-25 October 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 14-21 October. Gas-and-steam emissions with variable amounts of ash rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano, and ash plumes from explosions that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted 300 km NW, E, and SE during 14 and 18-19 October. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 October-18 October 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 7-14 October. Gas-and-steam emissions with variable amounts of ash rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano, and ash plumes from explosions that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted 300 km N, NE, E, and SE during 7-12 October. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 October-11 October 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 30 September-7 October. Gas-and-steam emissions with variable amounts of ash rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano, and ash plumes from explosions that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted 260 km E. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 September-4 October 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 23-30 September. Ash emissions rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano. During 23-24 September explosions generated ash plumes that rose as high as 6 km (19,700 ft) a.s.l. and drifted 165 km in multiple directions. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 September-27 September 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 16-23 September. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage and also down the SW flank. Satellite images showed a large and bright daily thermal anomaly at the volcano. During 20-22 September explosions generated ash plumes that rose as high as 7 km (23,000 ft) a.s.l. and drifted 100 km SW, E, and SE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 September-20 September 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 9-16 September. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage and also down the SW flank. Satellite images showed a large and bright daily thermal anomaly at the volcano. On 10, 13, and 15 September ash plumes rose as high as 7 km (23,000 ft) a.s.l. and drifted 50 km NE and SE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 September-13 September 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 2-9 September. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the E flank. A lava flow traveled down the Apakhonchich drainage and also down the SW flank. Satellite images showed a large and bright daily thermal anomaly at the volcano.

At 0943 and 1443 on 7 September explosions generated ash plumes that rose to altitudes of 6.5-7.5 km (21,300-24,600 ft) a.s.l. and drifted as far as 75 km SSW and ESE. The Aviation Color Code was raised to Red (the highest level on a four-color scale), and then lowered back to Orange within a few hours. Explosions at 1804 on 7 September produced ash plumes that rose as high as 7 km (23,000 ft) a.s.l. and drifted 45 km NE. At 0034, 0758, 1341, and 1850 on 8 September explosions generated ash plumes that rose to altitudes of 7-7.5 km (23,000-24,600 ft) a.s.l. and drifted as far as 145 km NE, NW, W, and SW. Ash plumes from explosions on 9 September did not go as high, rising to altitudes of 3-5 km (10,000-16,400 ft) a.s.l. and drifting 315-535 km SW. Minor ash deposits at Koryaksky and Avachinsky volcanoes were detected during 2100-2140; ash plumes continued to drift and dissipate over the Avachinsky bay.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 August-6 September 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 26 August-2 September. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage and also down the SW flank. Satellite images showed a large and bright daily thermal anomaly at the volcano, and ash plumes drifting 230 km NE, SE, S, and SW. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 August-30 August 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 19-26 August. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and bright daily thermal anomaly at the volcano. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 August-23 August 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 12-19 August. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large daily thermal anomaly at the volcano. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 August-16 August 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 5-12 August. Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting about 370 km SE and W during 9 and 11 August. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 August-9 August 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 29 July-5 August. Volcanic bombs that were ejected 200-300 m above the summit crater and 50 m above a cinder cone landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting about 200 km NE, E, and NW during 31 July, 1 August, and 3-4 August. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 July-2 August 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 22-29 July. Volcanic bombs that were ejected 200-300 m above the summit crater and 50 m above a cinder cone landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting over 140 km E during 22-23 and 26 July. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 July-26 July 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 15-22 July. Volcanic bombs were ejected 200-300 m above the summit crater and 50 m above a cinder cone, and landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting over 265 km SW and W during 18-19 July. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 July-19 July 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 8-15 July. Volcanic bombs were ejected 200-300 m above the summit crater and 50 m above a cinder cone, and landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting 170 km NE during 11-12 July. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 July-12 July 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 1-8 July. Volcanic bombs were ejected 200-300 m above the summit crater and 50 m above a cinder cone, and landed in the Apakhonchich drainage on the SE flank. A lava flow traveled down the Apakhonchich drainage. Satellite images showed a large and intense daily thermal anomaly at the volcano, and ash plumes drifting 350 km SW, S, and SE during 2-5 July. Video data showed that activity intensified on 6 July; strong explosions generated ash plumes that rose as high as 7.5 km (24,600 ft) a.s.l. Satellite images showed dense ash plumes drifting 400 km SE and E during 6-7 July. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 June-5 July 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 24 June-1 July. Satellite and video data showed a lava flow continuing to effuse on the SE flank, down the Apakhonchich drainage. Two rock avalanches down the Apakhonchich drainage were recorded by a webcam at 2115 and 2350 on 24 June; ash plumes drifted W and NW. Satellite images showed an intense daily thermal anomaly over the volcano, and gas-and-steam plumes that drifted about 60 km E and W during 27-28 June. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 June-28 June 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 17-24 June. Satellite and video data showed a lava flow continuing to effuse on the SE flank. Satellite images showed an intense thermal anomaly over the volcano, and an ash plume drifting almost 30 km E on 18 June. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 June-21 June 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 10-17 June. Satellite and video data showed a lava flow continuing to effuse on the SE flank. Satellite images showed an intense thermal anomaly over the volcano, and an ash plume drifting almost 50 km W on 13 June. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 June-14 June 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 3-10 June. Satellite and video data showed a lava flow continuing to effuse on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense thermal anomaly over the volcano. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 June-7 June 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 27 May-3 June. Satellite and video data showed a lava flow effusing on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense daily thermal anomaly over the volcano. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 May-31 May 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 20-27 May. Satellite and video data showed a lava flow effusing on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense daily thermal anomaly over the volcano. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 May-24 May 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 13-20 May. Satellite and video data showed a lava flow effusing on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense thermal anomaly over the volcano, and ash plumes drifting as far as 80 km E and SE on 13 and 16 May. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 May-17 May 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 6-13 May. Satellite and video data showed a lava flow effusing on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense thermal anomaly over the volcano. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 May-10 May 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 29 April-6 May. Satellite and video data showed a lava flow effusing on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense thermal anomaly over the volcano, and an ash cloud that drifted 88 km SE on 2 May. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 April-3 May 2016 Cite this Report

KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 21-29 April. Satellite and video data showed a lava flow effusing on the SE flank, moving down the Apakhonchich drainage. Satellite images showed an intense thermal anomaly over the volcano, and an ash cloud that drifted about 500 km SW during 23-24 April. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 April-26 April 2016 Cite this Report

KVERT reported that Strombolian explosions and gas-and-steam emission continued to be observed at Klyuchevskoy during 15-21 April. Satellite images showed an intense daily thermal anomaly over the volcano, and a robust gas-and-steam plume containing ash drifting 55 km NE on 15 April. At 0140 on 25 April a strong explosion generated an ash plume that rose to altitudes of 8-9 km (26,200-29,500 km) a.s.l. and, by 1428, had drifted over 450 km SW. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 April-19 April 2016 Cite this Report

KVERT reported that Strombolian explosions and gas-and-steam emission continued to be observed at Klyuchevskoy during 8-15 April. Satellite images showed an intense daily thermal anomaly over the volcano, and robust gas-and-steam plumes drifting 100 km SE on 10 April and NE on 14 April. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 April-12 April 2016 Cite this Report

KVERT reported that Strombolian explosions and gas-and-steam emission continued to be observed at Klyuchevskoy during 3-8 April. Satellite images showed a thermal anomaly during 1 and 5-7 April. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 March-5 April 2016 Cite this Report

KVERT reported strong gas-and-steam activity at Klyuchevskoy during 25 March-1 April. A weak thermal anomaly was detected over the volcano during 25 and 29-30 March. Strong Strombolian activity began at 2325 on 3 April, and satellite images on 5 April began registering a bright thermal anomaly. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 August-1 September 2015 Cite this Report

KVERT reported that a webcam recorded crater incandescence at Klyuchevskoy at 0344 on 28 August, indicating the onset of Strombolian activity. Strong gas-and-steam emissions were visible during the previous one or two days. The Aviation Color Code was raised to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 July-21 July 2015 Cite this Report

On 21 July KVERT reported that an eruption at Klyuchevskoy ended on 24 March, although activity during 1-10 May was characterized by gas-and steam plumes with minor amounts of ash and a thermal anomaly. Seismicity continued at a high level, and gas-and-steam emissions continued. The Aviation Color Code was lowered to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 May-12 May 2015 Cite this Report

KVERT reported that moderate activity continued at Klyuchevskoy during 1-9 May. Satellite images detected a daily weak thermal anomaly over the volcano, and gas-and-steam plumes containing ash drifting over 450 km SE during 2-5 May. The Aviation Color Code was lowered to Yellow on 13 May.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 April-28 April 2015 Cite this Report

KVERT reported that moderate gas-and-steam activity at Klyuchevskoy was recorded by the webcam during 16-17, 19, 21, and 23 April. Satellite images detected a weak thermal anomaly over the volcano during 16-17 and 23 April. A gas plume containing a small amount of ash drifted 147 km E on 21 April. On 26 April the Aviation Color Code was lowered to Yellow; KVERT noted that gas-and-steam activity and tremor continued.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 April-21 April 2015 Cite this Report

On 18 April KVERT reported that Strombolian activity at Klyuchevskoy continued. A webcam recorded a narrow ash plume that rose 1-2 km and drifted 100 km SE. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 April-14 April 2015 Cite this Report

KVERT reported that gas-and-steam emissions at Klyuchevskoy increased at 0840 on 13 April and continued at least through 1215 on 14 April. Incandescence at the summit was indicative of renewed Strombolian activity. The Aviation Color Code was raised to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 April-7 April 2015 Cite this Report

On 6 April KVERT reported that the Aviation Color Code for Klyuchevskoy was lowered to Green, noting that the explosive eruption had finished on 24 March. KVERT speculated that the continuing high seismicity reflected rebuilding of the magmatic system. Moderate gas-and-steam activity continued.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 March-24 March 2015 Cite this Report

KVERT reported that during 13-20 March the eruption at Klyuchevskoy continued but the energy of the explosions decreased significantly. Explosions generated ash plumes that rose to altitudes of 5-5.5 km (16,400-18,000 ft) a.s.l. During 16-17 March satellite images showed a weak thermal anomaly over the volcano and ash plumes that drifted 90 km E. Ash plumes were again detected in images during 22-23 March. On 25 March the Aviation Color Code was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 March-17 March 2015 Cite this Report

After a quiet period of 24 hours at Klyuchevskoy, volcanic-tremor magnitude significantly increased at 0500 on 10 March prompting KVERT to raise the Aviation Color Code to Orange. Video images showed moderate gas-and-steam activity while satellite images detected a gas-and-steam plume with small amounts of ash drifting about 92 km ESE at an altitude of 5 km (16,400 ft) a.s.l. During 10-11 March a weak thermal anomaly over the summit was detected.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 March-10 March 2015 Cite this Report

KVERT reported that a Strombolian and Vulcanian eruption at Klyuchevskoy continued during 27 February-6 March. Explosions generated ash plumes that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted 400 km E, SE, and NE. Satellite images showed a daily thermal anomaly over the volcano. The magnitude of seismic tremor significantly decreased at 0520 on 9 March, likely signifying the end of the explosive eruption. Only moderate emissions of steam and gas were observed and a thermal anomaly over the summit had been absent for the previous 10 hours. The Aviation Color Code was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 February-3 March 2015 Cite this Report

KVERT reported that during 20-27 February a Strombolian and Vulcanian eruption at Klyuchevskoy continued. Incandescence at the summit was visible and bombs were ejected 150 m above the crater. Explosions generated ash plumes that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. Satellite images showed a daily, big, bright thermal anomaly over the volcano and ash plumes that drifted 430 km mainly NE, E, and SE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 February-24 February 2015 Cite this Report

KVERT reported that during 13-20 February a Strombolian and Vulcanian eruption at Klyuchevskoy continued. Incandescence at the summit was visible and bombs were ejected 150 m above the crater. Explosions generated ash plumes that rose to altitudes of 5-8 km (16,400-26,200 ft) a.s.l.; ashfall was reported in Klyuchi Village (30 km NNE) during 13-16 February. A lava flow effused onto the E flank. Satellite images showed a daily, big, bright thermal anomaly over the volcano, and ash plumes drifted about 600 km mainly E, SE, and S. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 February-17 February 2015 Cite this Report

KVERT reported that during 6-13 February a Strombolian and Vulcanian eruption at Klyuchevskoy continued. Incandescence at the summit was visible and bombs were ejected 200-300 m above the crater. Explosions generated ash plumes that rose to altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l.; ashfall was reported in Kozyrevsk Village (50 km W) on 7 February and Klyuchi Village (30 km NNE) on 11 February. A lava flow effused onto the E flank. Satellite images showed a daily, big, bright thermal anomaly over the volcano, and ash plumes drifting about 400 km mainly NW and N at altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l.

On 15 February at 1035 the webcam recorded ash plumes rising to altitudes of 6-6.5 km (19,700-21,300 ft) a.s.l. and drifting 74 km E. At 1211, 1347, and 1524 ash plumes rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted 110-232 km E and ESE. The Aviation Color Code was raised to Red. At 1656 ash plumes rose to altitudes of 7.5-7.8 km (24,600-25,600 ft) a.s.l. and drifted 232 km ESE. The Aviation Color Code was lowered to Orange. At 1512 on 16 February ash plumes identified in satellite images rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted 270 km S. The next day, at 0641, 1503, and 1505, ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted 114-240 km SE.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 February-10 February 2015 Cite this Report

KVERT reported that during 30 January-6 February a Strombolian and Vulcanian eruption at Klyuchevskoy continued. Incandescence at the summit was visible and bombs were ejected 200-300 m above the crater. Explosions generated ash plumes that rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l.; ashfall was reported in Klyuchi Village (30 km NNE) on 5 February. A lava flow effused onto the E flank. Satellite images showed a daily, big, bright thermal anomaly over the volcano, and ash-and-gas plumes drifting in multiple directions at altitudes of 5.5-6 km (18,000-19,700 ft) a.s.l. During 4-5 February ash plumes drifted about 1,000 km NW and N. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 January-3 February 2015 Cite this Report

KVERT reported that during 23-30 January a Strombolian and Vulcanian eruption at Klyuchevskoy continued. Incandescence at the summit was visible and bombs were ejected 200-300 m above the crater. Explosions generated ash plumes that rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l.; ashfall was reported in Klyuchi Village (30 km NNE) and near the Khapitsa River on 27 January, and in Kozyrevsk Village (50 km W) on 28 January. A lava flow effused onto the E flank; phreatic explosions at the lava flow front produced gas-and-steam clouds with minor amounts of ash that rose 7-8 km (23,000-26,200 ft) a.s.l. during 27-28 January. Satellite images showed a daily, big, bright thermal anomaly over the volcano, and ash-and-gas plumes drifting 300 km W, N, NE, E, and SE at altitudes of 5.5-7 km (18,000-23,000 ft) a.s.l. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 January-27 January 2015 Cite this Report

KVERT reported that during 16-23 January a Strombolian and Vulcanian eruption at Klyuchevskoy continued. A lava flow effused onto the SE flank. Incandescence at the summit was visible and bombs were ejected 200-300 m above the crater. Explosions generated ash plumes that rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l.; ashfall was reported in Klyuchi Village (30 km NNE) on 21 January. Satellite images showed a daily, big, bright thermal anomaly over the volcano, and ash plumes drifting 210 km SW, NW, and NE at altitudes of 5-6 km (16,400-19,700 ft) a.s.l. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 January-20 January 2015 Cite this Report

KVERT reported that during 9-16 January a Strombolian and Vulcanian eruption at Klyuchevskoy continued and a new lava flow started to effuse onto the SE flank. Incandescence at the summit was visible and bombs were ejected 200-300 m above the crater. During 11-15 January explosions generated ash plumes that rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. Ashfall was reported in Kozyrevsk Village (50 km W) on 11 January. Satellite images showed ash plumes drifting 160 km SW and NE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 January-13 January 2015 Cite this Report

KVERT reported that a Strombolian eruption began at Klyuchevskoy on 1 January; bombs were ejected 300-400 m above the crater. On 10 January strong gas-and-steam emissions containing ash were recorded by the webcam. Video images also indicated a possible lava flow on the S flank. The Aviation Color Code was raised to Orange. Strombolian and Vulcanian activity continued during 11-12 January, and explosions generated ash plumes that rose 5-7 km (16,400-23,000 ft) a.s.l. Satellite images on 11 January showed a 12.5-km-wide, 36.8-km-long ash plume drifting at an altitude of 5 km (16,400 ft) a.s.l. On 12 January an ash plume rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted 35 km.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 December-6 January 2015 Cite this Report

Based on seismic data from KB GS RAS, KVERT reported that seismic activity at Klyuchevskoy began to increase during 19-20 December and then increased again on 31 December. Although cloud cover prevented views of the volcano during 31 December-1 January, a thermal anomaly was detected in satellite images on 1 January, possibly indicating that a Strombolian eruption had begun. The Aviation Color Code was raised to Yellow on 2 January.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 January-7 January 2014 Cite this Report

On 2 January KVERT reported that the explosive eruption at Kliuchevskoi had finished on 20 December 2013; the last strong explosion was detected on 17 December 2013. Video images showed gas-and-steam plumes continuing to rise from the volcano. Satellite images detected thermal anomalies over the summit and the lava flow on the SW flank; both areas were cooling. The Aviation Color Code was lowered to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 December-31 December 2013 Cite this Report

On 27 December KVERT reported that the explosive eruption at Kliuchevskoi had finished; the last strong explosion was detected on 17 December. Video images showed gas-and-steam plumes rising from the volcano during the previous weeks. Satellite images continued to detect thermal anomalies over the summit and the lava flow on the SW flank. The Aviation Color Code was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 December-24 December 2013 Cite this Report

KVERT reported weak seismic activity at Kliuchevskoi during 13-20 December, and video images showed moderate gas-and-steam activity. Satellite images detected daily weak thermal anomalies over the summit and the SW flank. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 December-17 December 2013 Cite this Report

KVERT reported that the explosive eruption at Kliuchevskoi continued during 6-13 December. Seismicity increased on 6 December but then declined on 10 December; during this period video images showed ash plumes rising to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. Satellite images detected a weak thermal anomaly daily, and ash plumes that drifted 1,200 km E during 6-8 December, NW during 9-10 December, and E and SE during 10-11 December. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 December-10 December 2013 Cite this Report

On 7 December activity at Kliuchevskoi significantly increased, prompting KVERT to raise the Alert Level to Red. Ash plumes rose to altitudes of 5.5-6 km (18,000-19,700 ft) a.s.l. and drifted more than 212 km NE and over 1,000 km E. According to a news article, a warning to aircraft was issued for the area around the volcano. The next day KVERT lowered the Alert Level to Orange. Ash plumes rose to altitudes of 5-5.5 km (16,400-18,000 ft) a.s.l. and drifted NE.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); United Press International (UPI)

27 November-3 December 2013 Cite this Report

KVERT reported that moderate seismic activity continued at Kliuchevskoi during 22-29 November. Video data showed Strombolian activity during that period. Satellite images recorded a daily thermal anomaly on the volcano; gas-and-steam plumes containing small amounts of ash were visible drifting 90 km SE on 25 November. On 3 December KVERT noted that since 19 November ash-plume altitudes had been decreasing. The Aviation Color Code was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 November-26 November 2013 Cite this Report

KVERT reported that at 1235 on 17 November an ash plume from Kliuchevskoi, detected in satellite images, rose to an altitude of 6.5 km (19,700 ft) a.s.l. and drifted 160 km NE. At 1322 an ash plume rose to an altitude of 7km (23,000 ft) a.s.l. and drifted 130 km NE. Video data then showed a high-intensity explosion and Strombolian activity prompting KVERT to raise the Aviation Color Code to Orange.

At 1416 on 19 November seismicity indicated a strong explosion, and observers reported that ash plumes rose to altitudes of 10-12 km (32,800-39,400 ft) a.s.l. and drifted SE. The Aviation Color Code was raised to Red. Later that day the altitudes of the ash plumes were lower; video images showed ash plumes rising to altitudes of 5-5.5 km(16,400-18,000 ft) a.s.l. and drifting NE. The Aviation Color Code was lowered to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 October-5 November 2013 Cite this Report

The Aviation Color Code was lowered to Yellow on 30 October. There was ongoing activity during the past week, including moderate seismicity. Video recordings captured Strombolian activity and strong gas-and-steam events. Satellite remote sensing detected a thermal anomaly over the volcano caused by the continuation of the flank eruption; lava flows effused on the SW and SE flanks.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 October-29 October 2013 Cite this Report

KVERT reported that at 0100 on 21 October a sharp decrease in seismicity was detected at Kliuchevskoi and only fumarolic activity was observed. The Aviation Color Code was lowered to Orange. Strombolian activity and the effusion of several lava flows continued through 25 October. Satellite images showed aerosol plumes over Canada during 20-23 October.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 October-22 October 2013 Cite this Report

KVERT reported that a strong explosion from a new cinder cone low on Kliuchevskoi’s SW flank occurred between 2020 and 2030 on 11 October. An ash plume rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted E.

Activity increased on 15 October, prompting KVERT to raise the Aviation Color Code to Red at 1311. Ash plumes rose to altitudes of 7-8 km (23,000-26,200 ft) a.s.l. and drifted 140 km SSW. Phreatic explosions on the SW flank generated ash plumes that rose 3-4 km (9,800-13,100 ft) a.s.l. Satellite images showed an ash plume rising to an altitude of 7.5 km (24,600 ft) a.s.l. at 1419 and drifting 103 km SSW. Activity increased again; ash plumes rose to altitudes of 9 km (29,500 ft) a.s.l. at 1655 and 10 km (32,800 ft) a.s.l. afterwards. Ash plumes drifted SSW and S. At 2056 KVERT lowered the Aviation Color Code to Orange and noted that although activity had slightly decreased it still remained high. Ash plumes rose 8 km (26,200 ft) a.s.l. and drifted ENE. Phreatic explosions at the SW flank continued, as well as lava flows on the SW, W, and SE flanks.

At 0815 on 16 October satellite images detected ash plumes that rose to altitudes of 2-3 km (6,600-9,800 ft) a.s.l. and drifted 480 km NNW. Activity again increased and at 1143 KVERT issued a notice stating that the Aviation Color Code was again being raised to Red. Seismic data indicated that ash plumes rose to an altitude of 10 km (32,800 ft) a.s.l. Clouds prevented direct observations but satellite images showed ash plumes drifting NW. At 1624 satellite images showed ash plumes drifting WSW at altitudes of 7-7.5 km (23,000-24,600 ft) a.s.l. Strombolian and Vulcanian explosions continued. Activity again slightly decreased; the Aviation Color Code was lowered to Orange. Minor ashfall was reported in Mayskoe Village.

During 16-17 October the melting of the Bogdanovich glacier due to the volcanic activity caused increased water flow in the Studenaya River, which destroyed part of a road near Kozyrevsk village (about 50 km W).

On 18 October the Aviation Color Code was again raised to Red but lowered to Orange later that day. Ash plumes rose to altitudes of 8-9 km (26,200-29,500 ft) a.s.l. and drifted 20-100 km SE. Strombolian activity continued and several lava flows continued to effuse onto the W, SW, and SE flanks. At 0559 on 19 October ash plumes observed in satellite images drifted 630 km SE at altitudes of 8-9 km (26,200-29,500 ft) a.s.l. The Aviation Color Code was raised to Red. Ash plume altitudes fluctuated between 7-8 km (23,000-26,200 ft) a.s.l. later that day. A large amount of ash continued to drift 600 km SE. At 0100 on 21 October a sharp decrease in seismicity was detected and only fumarolic activity was observed. The Aviation Color Code was lowered to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 September-24 September 2013 Cite this Report

KVERT reported that moderate seismic activity at Kliuchevskoi was detected during 13-20 September. A video camera recorded incandescence from the summit and the WSW flank at night, and gas-and-steam plumes containing minor amounts of ash. Strombolian the activity continued and a lava flow effused onto the W and SW flanks. A large thermal anomaly from the lava dome was detected daily in satellite images. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 September-17 September 2013 Cite this Report

KVERT reported that moderate seismic activity at Kliuchevskoi was detected during 6-13 September. A video camera recorded incandescence from the summit and the WSW flank at night, and gas-and-steam plumes containing minor amounts of ash. Strombolian activity continued and a lava flow effused onto the W and SW flanks. A large thermal anomaly from the lava dome was detected in satellite images. On 14 September, KVERT stated that lava flows on the NW, W, and SW flanks may soon interact with glaciers, potentially producing tall ash plumes from phreatic explosions. The Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 September-10 September 2013 Cite this Report

KVERT reported that moderate seismic activity at Kliuchevskoi was detected during 30 August-6 September. A video camera recorded incandescence from the summit and WSW flank at night, and gas-and-steam plumes containing minor amounts of ash. Strombolian activity continued and a lava flow effused onto the SW flank. A large thermal anomaly from the lava dome was detected in satellite images.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 August-3 September 2013 Cite this Report

KVERT reported that moderate seismic activity at Kliuchevskoi was detected during 23-30 August. A video camera recorded incandescence from the summit at night and gas-and-steam plumes containing minor amounts of ash. A large thermal anomaly from the lava dome was detected in satellite images. Strombolian activity that began on 15 August continued; a new lava flow effused onto the SW flank on 26 August, producing a thermal anomaly detected in satellite images. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 August-27 August 2013 Cite this Report

KVERT reported that moderate seismic activity at Kliuchevskoi was detected during 16-23 August. A video camera recorded incandescence from the summit at night, and gas-and-steam plumes containing minor amounts of ash rising to an altitude of 5.5 km (18,000 ft) a.s.l. A thermal anomaly from the lava dome was detected in satellite images during 16-18 and 20-23 August; cloud cover obscured views on 19 August. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 August-20 August 2013 Cite this Report

Based on seismic data from the Kamchatka Branch of Geophysical Services (KBGS; Russian Academy of Sciences), KVERT reported that a Strombolian eruption from Kliuchevskoi began at 1830 on 15 August. Video images recorded incandescence from the crater that night, and gas-and-steam plumes containing minor amounts of ash rising as high as 6 km (19,700 ft) a.s.l. and drifting NE during 15-16 August. Satellite images detected a large, bright thermal anomaly during 15-16 August. The Aviation Color Code was raised to Yellow, the second lowest of a four-color scale. Gas-and-steam plumes containing minor amounts of ash rose to an altitude of 5.5 km (18,000 ft) a.s.l. during 16-17 August. Incandescence from the crater at night and a thermal anomaly in satellite images continued to be reported during 17-19 August.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 March-19 March 2013 Cite this Report

KVERT reported that activity at Kliuchevskoi decreased in late 2012, around the same time the Tolbachik eruption started. In mid-January 2013 seismic activity decreased and Strombolian activity ceased. Starting in February incandescence at the summit and thermal anomalies were not observed. Weak seismic activity continued. On 18 March the Aviation Color Code was lowered to Green, the lowest level.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 January-29 January 2013 Cite this Report

KVERT reported that during 18-25 January video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. Views from satellite were obscured by cloud cover. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 December-25 December 2012 Cite this Report

KVERT reported that during 14-21 December video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A thermal anomaly was detected in satellite images on 16 and 18 December; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 December-18 December 2012 Cite this Report

KVERT reported that during 7-14 December video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A thermal anomaly was detected in satellite images during 7-8, 10, and 12-13 December; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 December-11 December 2012 Cite this Report

KVERT reported that during 30 November-7 December video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A weak thermal anomaly was detected in satellite images during 1 and 4-6 December; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 November-4 December 2012 Cite this Report

KVERT reported that during 23-30 November video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions. A weak thermal anomaly was detected in satellite images during 23-26 November; cloud cover obscured views on the other days. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 October-23 October 2012 Cite this Report

KVERT reported moderate seismic activity at Kliuchevskoi during 12-19 October. Strombolian activity was observed during 13-15 October; clouds prevented views on the other days. A weak thermal anomaly was detected in satellite imagery during 14-15 October. The Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 October-16 October 2012 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi had been gradually increasing since June; episodes of volcanic tremor were first detected on 21 June and continued through 14 October. A weak thermal anomaly was detected in satellite imagery during 1 September-14 October. Strombolian activity was observed at night during 14-15 October. The Aviation Color Code was raised to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 November-8 November 2011 Cite this Report

The Tokyo VAAC reported that a possible ash plume from Kliuchevskoi, drifting at an altitude of 6.7 km (22,000 ft) a.s.l., was observed in satellite imagery. The VAAC noted that the ash plume may have been from Bezymianny.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)

29 June-5 July 2011 Cite this Report

Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that an eruption from Kliuchevskoi on 3 July produced a plume that rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)

1 June-7 June 2011 Cite this Report

KVERT reported that during 27 May-3 June seismic activity at Kliuchevskoi was detected. Moderate steam-and-gas activity was observed on 30 May and 1 June; cloud cover prevented observations on the other days of the week. The Aviation Color Code was lowered to Green.

The Tokyo VAAC reported that on 6 June a possible eruption detected in satellite imagery produced a plume that rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted NE. The VAAC stated that the ash could have also originated at Bezymianny.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

25 May-31 May 2011 Cite this Report

Based on video data and ground-based observations, KVERT reported that on 29 May an ash plume from Kliuchevskoi rose to an altitude of 5 km (16,400 ft) a.s.l. and drifted SW. The Aviation Color Code was raised to Orange. No activity was noted on 30 May and the volcano was obscured by clouds the next day. The Aviation Color Code was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 March-5 April 2011 Cite this Report

Based on analyses of satellite imagery, the Tokyo VAAC reported that a possible eruption from Kliuchevskoi on 30 March produced a plume that rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted E. Subsequent images that day showed continuing ash emissions that later dissipated. The Aviation Color Code remained at Green.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

9 February-15 February 2011 Cite this Report

Although moderate seismic activity was recorded at Kliuchevskoi during 4-11 February, KVERT reported that seismicity had essentially decreased. Gas-and-steam activity was observed during 4-7 February; clouds prevented observations on later days. Gas-and-steam plumes drifted 20 km NE on 5 and 7 February. Satellite imagery showed a weak thermal anomaly over the crater on 6 and 7 February. The Aviation Color Code was lowered to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 December-21 December 2010 Cite this Report

KVERT reported that during 10-17 December seismic activity at Kliuchevskoi did not exceed background levels. Steam-and-gas emissions were observed during 10-13 December. Satellite imagery showed a weak thermal anomaly over the crater on 11 and 12 December. The Aviation Color Code level was lowered to Yellow.

The Tokyo VAAC reported that on 20 December a possible eruption detected in satellite imagery produced a plume that rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted N.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

8 December-14 December 2010 Cite this Report

KVERT reported that during 3-10 December seismic activity at Kliuchevskoi was slightly above background levels. Satellite imagery showed a weak thermal anomaly over the crater during 3 and 6-8 December. Gas-and-steam plumes sometimes containing ash were observed during 3-4 and 8-9 December. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

1 December-7 December 2010 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was slightly above background levels during 26-27 November, and did not exceed background levels during 28 November-3 December. Satellite imagery showed gas-and-ash plumes drifting 430 km N and NE during 26-29 November and a weak thermal anomaly over the crater on 26, 28, and 29 November. Ash plumes were seen rising to an altitude of 6.3 km (20,700 ft) a.s.l. on 26 and 29 November and 1 December. Ash fell in Kozyrevsk (about 50 km W) on 27 November and in Klyuchi (30 km NNE) on 28 November. Strombolian activity was observed on 1 and 2 December. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 November-30 November 2010 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi did not exceed background levels during 19-26 November. Strong fumarolic activity was observed daily and an ash plume rose to an altitude of 5 km (16,400 ft) a.s.l. on 24 November. Satellite imagery showed a thermal anomaly over the crater during 19-21 November and a gas-and-steam plume that drifted 111 km NE on 24 November. The Aviation Color Code level was raised to Orange.

Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 25 November an ash plume rose to an altitude of 7.9 km (26,000 ft) a.s.l. and drifted E. Possible eruptions detected in satellite imagery on 27 and 29 November produced plumes that rose to altitudes of 5.8 km and 6.7 km (19,000 and 22,000 ft) a.s.l., respectively, and drifted NE.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

17 November-23 November 2010 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 12-14 November and at background levels during 15-19 November. A weak thermal anomaly over the volcano was detected daily in satellite imagery. Fumarolic activity was observed during 16-18 November; cloud cover prevented observations on the other days. Satellite imagery also showed an ash plume that drifted 40 km NE on 13 November and a gas-and-steam plume that drifted 28 km NE the next day. The Aviation Color Code level remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 November-16 November 2010 Cite this Report

KVERT reported that during 8-10 November seismic activity at Kliuchevskoi was at background levels. During 9-10 November strong fumarolic activity was seen and a weak thermal anomaly over the crater was observed in satellite imagery. Based on analyses of satellite imagery and information from KVERT, the Tokyo VAAC reported that on 13 November an eruption produced a plume that drifted NE. Later that day, images showed that the ash had dissipated. The Aviation Color Code level remained at Yellow.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

3 November-9 November 2010 Cite this Report

KVERT reported that during 29 October-3 November seismic activity at Kliuchevskoi was above background levels and Strombolian activity was observed. Satellite imagery analyses showed a thermal anomaly over the volcano and ash plumes that drifted 480 km SE. Vulcanian activity produced ash plumes that rose to an altitude of 7 km (23,000 ft) a.s.l. during 31 October and 1-4 November. Seismicity sharply decreased on 4 November, and only gas-and-steam activity was observed. On 9 November, KVERT reported that the eruption that began in August 2009 had finished on 4 November and that seismicity had continued to decrease. The Aviation Color Code level was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 October-2 November 2010 Cite this Report

KVERT reported that during 22-29 October seismic activity at Kliuchevskoi was above background levels and Strombolian activity was observed. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano and two lava flows descending the W and SW flanks from the summit crater. Ash plumes also detected in imagery drifted more than 2,300 km E. Ash plumes rose to altitudes of 8-9 km (26,200-29,500 ft) a.s.l. during 22-25 and 27 October. The Aviation Color Code level remained at Red. A news article from 29 October stated that ash from Kliuchevskoi and Shiveluch caused area flight diversions.

On 30 October explosive activity decreased along with the magnitude of volcanic tremor. Based on visual observations and analysis of satellite imagery, ash plumes rose to altitudes of 5-5.5 km (16,400-18,000 ft) a.s.l. and drifted 100 km SE. The Aviation Color Code level was lowered to Orange. The Tokyo VAAC reported that, based on analyses of satellite imagery and information from KVERT, eruptions on 31 October and 2 November, and a possible eruption on 1 November produced ash plumes that rose to altitudes of 5.2-6.7 km (17,000-22,000 ft) a.s.l. and drifted SE and E.

Sources: Associated Press; Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

20 October-26 October 2010 Cite this Report

KVERT reported that during 15-22 October seismic activity from Kliuchevskoi was above background levels and two lava flows from the summit crater traveled down the SW and W flanks. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano and ash plumes that drifted 420 km E and SE. Strombolian activity, observed every day, ejected material 250 m above the crater. Ash plumes rose to an altitude of 7.5 km (24,600 ft) a.s.l. during 20-21 October and to an altitude of 6.5 km (21,300 ft) a.s.l. on the other days during 15-22 October. The Aviation Color Code level remained at Orange.

On 23 October, KVERT reported increased seismicity, characterized by an abrupt change in volcanic tremor, and explosive activity. Ash plumes rose to altitudes of 8-9 km (26,200-29,500 ft) a.s.l. and drifted more than 300 km N. The Aviation Color Code level was raised to Red. The next day the magnitude of tremor decreased and gas-and-steam plumes rose to an altitude of 6.5 km (21,300 ft) a.s.l. Gas-and-steam plumes possibly containing ash drifted SE. The Aviation Color Code level was lowered to Orange. On 25 October, the magnitude of volcanic tremor fluctuated. Ash plumes rose to altitudes of 8-8.5 km (26,200-27,900 ft) a.s.l. and drifted SE. The Aviation Color Code level was again raised to Red. The VAAC reported on 26 October that ash was observed in satellite imagery.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

13 October-19 October 2010 Cite this Report

KVERT reported that during 8-15 October seismic activity from Kliuchevskoi was above background levels and lava from the summit crater flowed down the SW and W flanks. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. Strombolian activity was observed during 7-11 October. Daily gas-and-steam plumes rose to an altitude of 5.8 km (19,000 ft) a.s.l., but on 11 October the plumes rose to an altitude of 7.8 km (25,600 ft) a.s.l. Ash plumes seen in satellite imagery drifted 90 km NE and E during 10 and 12-14 October. The Tokyo VAAC reported that ash was seen in satellite imagery on 16 October. The next day possible eruptions reported by KVERT, and seen in satellite imagery, produced plumes that rose to altitudes of 5.2-5.8 km (17,000-19,000 ft) a.s.l. and drifted SE. Ash seen in imagery on 18 October may have been from an eruption earlier that day. Ash again seen in satellite imagery from a possible eruption on 19 October rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted N. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

6 October-12 October 2010 Cite this Report

KVERT reported that during 1-8 October seismic activity from Kliuchevskoi was above background levels and lava from the summit crater flowed down the SW flank. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. Strombolian activity was observed almost every day, and gas-and-ash plumes rose to an altitude of 6.3 km (20,700 ft) a.s.l. Ash plumes seen in satellite imagery drifted 50 km SE during 5-6 October. The Aviation Color Code level remained at Orange. Based on analyses of satellite imagery and information from KVERT, the Tokyo VAAC reported ash drifting NE on 11 October. The next day an eruption seen in satellite imagery produced an ash plume that rose to an altitude of 10.1 km (33,000 ft) a.s.l. and drifted E. A subsequent notice stated that ash had dissipated. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

29 September-5 October 2010 Cite this Report

KVERT reported that during 24 September-1 October seismic activity from Kliuchevskoi was above background levels and lava from the summit crater flowed down the SW flank. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. Ash plumes were seen rising to altitudes of 6.5-7 km (21,300-23,000 ft) a.s.l. on 22 and 24 September, and Strombolian activity was observed during 23, 25, and 28-29 September. Ash plumes seen in satellite imagery drifted 185 km E on 22 and 28 September and 78 km W on 24 and 25 September. KVERT noted that eruptive activity from Kliuchevskoi had been continuous since 1 September 2009. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 September-28 September 2010 Cite this Report

KVERT reported that during 17-24 September seismic activity from Kliuchevskoi was above background levels and lava from the summit crater flowed down the SW flank. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. Strombolian activity was observed during 17 and 20-21 September, and ash plumes were seen rising to altitudes of 6.5-7 km (21,300-23,000 ft) a.s.l. on 20 and 21 September. Satellite imagery showed ash plumes drifting about 60 km W on 19 September and about 240 km E on 20 and 21 September. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 September-21 September 2010 Cite this Report

KVERT reported that during 10-17 September seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW flank. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. During 9-15 September ash plumes rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted 575 km S and SE based on analyses of satellite imagery and visual observations. Strombolian activity was seen on 11 September. Based on analyses of satellite imagery and information from KEMSD, the Tokyo VAAC reported that possible eruptions on 21 and 22 September produced ash plumes that rose to altitudes of 5.2-6.1 km (17,000-20,000 ft) a.s.l. and drifted E. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

8 September-14 September 2010 Cite this Report

KVERT reported that during 3-10 September seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW and NW flanks. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. During 2-4 September ash plumes seen in satellite imagery drifted 150 km S and SW at an altitude of 6.5 km (21,300 ft) a.s.l. Phreatic bursts on the SW flank were observed on 5 September and Strombolian activity was seen during 5-7 September. Seismic data suggested that during 5-6 September ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l.

Based on analyses of satellite imagery, the Tokyo VAAC reported that a possible eruption on 12 September produced a plume that rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted SE. On 13 September an ash plume rose to an altitude of 9.8 km (32,000 ft) a.s.l. and drifted NE according to information sent from the Yelizovo Airport (UHPP). Ash was seen in subsequent satellite images during 13-14 September. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

1 September-7 September 2010 Cite this Report

KVERT reported that 27 August-3 September seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW flank. Satellite imagery analyses showed a large and intense daily thermal anomaly over the volcano. On 27 August, activity increased; ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted 120 km SE. Strombolian activity was observed during 27-30 August. Phreatic explosions occurred on the SW flank on 29 and 30 August. Ash plumes rose to an altitude of 6.5 km (21,300 ft) a.s.l. on 30 August and drifted 278 km SE.

Based on analyses of satellite imagery and information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported a possible eruption on 3 September. Subsequent images showed continuing emissions. Later that day a notice stated that ash had dissipated. Another possible eruption that day produced a plume that rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted E. During 4-7 September eruptions reported by KVERT and seen in satellite imagery produced ash plumes that rose to altitudes of 5.2-7 km (17,000-23,000 ft) a.s.l. and drifted NW, E, and SE. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

25 August-31 August 2010 Cite this Report

KVERT reported that 20-27 August seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW flank. Strombolian activity and gas-and-ash emissions were observed on 20 and 21 August. Cloud cover prevented observations the other days. Satellite imagery analyses showed a large and intense daily thermal anomaly from the volcano and ash plumes that drifted more than 200 km SE on 20 August. Based on analyses of satellite imagery and information from KEMSD, the Tokyo VAAC reported that an eruption on 28 August produced plumes that rose to altitudes of 7.6-10.4 km (25,000-34,000 ft) a.s.l. and drifted SE. Satellite imagery showed a possible eruption on 30 August. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

18 August-24 August 2010 Cite this Report

KVERT reported that 13-20 August seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW flank. Strombolian activity and gas-and-ash emissions were observed during 14-16 August. Cloud cover prevented observations the other days. Satellite imagery analyses showed a large and intense daily thermal anomaly from the volcano and ash plumes that drifted more than 325 km SE. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 August-17 August 2010 Cite this Report

KVERT reported that during 6-13 August seismic activity from Kliuchevskoi was above background levels and lava flowed down the SW flank. Strombolian activity and gas-and-ash emissions were observed during 6 and 8-12 August. Cloud cover prevented observations the other days. Satellite imagery analysis showed a large and intense daily thermal anomaly on the volcano. Based on analyses of satellite imagery, the Tokyo VAAC reported a possible eruption on 16 August. A subsequent notice stated that ash had dissipated. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

4 August-10 August 2010 Cite this Report

KVERT reported that 30 July-6 August seismic activity from Kliuchevskoi was above background levels and lava flowed down the SSE flank. Strombolian activity and gas-and-ash emissions were observed during 29-30 July and 4-5 August. Cloud cover prevented observations the other days. Satellite imagery analysis showed a large daily thermal anomaly from the volcano and a gas-and-ash plume that drifted 65 km NW on 30 July. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 July-3 August 2010 Cite this Report

KVERT reported that during 23-30 July seismic activity from Kliuchevskoi was above background levels and lava flowed down the SSE flank. Strombolian activity and gas-and-ash emissions were observed during 23-24 and 29 July. Cloud cover prevented observations the other days. Satellite imagery analysis showed a large daily thermal anomaly from the volcano and gas-and-ash plumes that drifted 145 km SW on 28 July. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 July-27 July 2010 Cite this Report

KVERT reported that during 16-23 July seismic activity from Kliuchevskoi was above background levels and Strombolian activity was seen. Gas-and-steam activity was noted with ash plumes periodically rising to an altitude of 6.3 km (20,700 ft) a.s.l. Effusive lava flows descended the SSW flank. Satellite imagery analysis showed a large daily thermal anomaly from the volcano and ash plumes that drifted about 55-160 km SW, SE, and NE. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 July-20 July 2010 Cite this Report

KVERT reported that during 9-16 July seismic activity from Kliuchevskoi was above background levels. Satellite imagery analysis showed a large daily thermal anomaly over the volcano and a gas-and-ash plume that drifted 45 km NW on 14 July. Strombolian activity and gas-and-ash emissions were observed during 9, 12, and 14-15 July. Ash plumes occasionally rose to an altitude of 6.8 km (22,300 ft) a.s.l. Based on analyses of satellite imagery and information from KVERT, the Tokyo VAAC reported a possible eruption on 17 July. Ash was seen in satellite imagery and then later dissipated. An eruption on 19 July and a possible eruption the next day produced plumes that rose to altitudes of 5.2-5.5 km (17,000-18,000 ft) a.s.l. and drifted SW and SE. The Aviation Color Code level remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

7 July-13 July 2010 Cite this Report

KVERT reported that during 2-9 July seismic activity from Kliuchevskoi was above background levels. Satellite imagery analysis showed a large daily thermal anomaly over the volcano and a gas-and-steam plume that drifted 76 km S on 2 July. Ash plumes occasionally rose to an altitude of 5.3 km (17,400 ft) a.s.l., and gas-and-steam activity was seen during 2-4 July. According to a news article, lava flowed from a fissure during 8-9 July. The Aviation Color Code level remained at Orange.

Sources: Itar-Tass News; Kamchatkan Volcanic Eruption Response Team (KVERT)

30 June-6 July 2010 Cite this Report

KVERT reported that during 25 June-2 July seismic activity from Kliuchevskoi was above background levels and Strombolian activity was observed on 24 and 29 June. Ash plumes occasionally rose to an altitude of 5.3 km (17,400 ft) a.s.l. Satellite imagery analysis revealed a large daily thermal anomaly from the volcano and an ash plume that drifted 32 km S on 1 July. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 June-29 June 2010 Cite this Report

KVERT reported that during 18-25 June seismic activity from Kliuchevskoi was above background levels and Strombolian activity was sometimes observed. Ash plumes occasionally rose to an altitude of 5.5 km (18,000 ft) a.s.l. Satellite imagery analysis revealed a large daily thermal anomaly from the volcano and ash plumes that drifted 120 km in multiple directions during 19 and 22-23 June. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 June-22 June 2010 Cite this Report

KVERT reported that during 11-18 June seismic activity from Kliuchevskoi was above background levels and Strombolian activity was observed. Ashfall was reported in Klyuchi, 30 km NNE on 11 June. Ash plumes occasionally rose to an altitude of 5.5 km (18,000 ft) a.s.l. during 13-16 June. Satellite imagery analysis revealed a large daily thermal anomaly from the volcano and ash plumes that drifted 40 km SE on 13 and 15 June. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 June-15 June 2010 Cite this Report

KVERT reported that during 4-11 June seismic activity from Kliuchevskoi was above background levels and Strombolian activity was seen. Gas-and-steam plumes, occasionally containing a small amount of ash, were also noted. On 5 June ash plumes rose to an altitude of 7.3 km (24,000 ft) a.s.l. Satellite imagery revealed a large daily thermal anomaly from the volcano, and ash plumes that drifted 60-190 km NE on 5 and 8 June. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 June-8 June 2010 Cite this Report

KVERT reported that during 28 May-4 June seismic activity from Kliuchevskoi was above background levels and Strombolian activity was seen. Gas-and-steam plumes occasionally containing a small amount of ash were also noted. Satellite imagery revealed a large daily thermal anomaly from the volcano, and ash plumes that drifted 40 km NW on 28 and 31 May. On 1 June an ash plume rose to an altitude of 7.3 km (24,000 ft) a.s.l. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 May-1 June 2010 Cite this Report

KVERT reported that during 21-28 May seismic activity from Kliuchevskoi was above background levels and Strombolian activity was seen. Gas-and-steam plumes occasionally containing a small amount of ash were also noted. During 23-26 May observed ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. Satellite imagery revealed a large daily thermal anomaly from the volcano, and ash plumes that drifted 185 km in multiple directions on 24 and 26 May. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 May-25 May 2010 Cite this Report

KVERT reported that during 14-21 May seismic activity from Kliuchevskoi was above background levels and Strombolian activity was seen. Gas-and-steam plumes containing a small amount of ash were noted during 13-18 May. Satellite imagery revealed a large daily thermal anomaly from the volcano, and ash plumes that drifted 20-145 km E on most days. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 May-18 May 2010 Cite this Report

KVERT reported that during 7-14 May seismic activity from Kliuchevskoi was above background levels and Strombolian activity was seen. Gas-and-steam plumes containing a small amount of ash were noted during 6 and 8-12 May. Satellite imagery revealed a large daily thermal anomaly from the volcano, and a gas-and-ash plume that drifted 21 km N on 7 May. Based on information from KVERT, the Tokyo VAAC reported that on 18 May an ash plume rose to an altitude of 5.8 km (19,000 ft) a.s.l. and drifted NE. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

5 May-11 May 2010 Cite this Report

KVERT reported that during 30 April-7 May seismic activity from Kliuchevskoi was above background levels. Ground observations were prevented due to meteorological cloud cover. Satellite imagery revealed a large daily thermal anomaly from the volcano. Ash plumes drifted 125 km N on 2 May and 70 km W at an altitude of 5.5 km (18,000 ft) a.s.l. on 3 May. Gas-and-steam plumes drifted 55 km W and SW both days. Based on information from KEMSD, the Tokyo VAAC reported that on 10 May an eruption produced a plume that rose to an altitude of 6.1 km (20,000 ft) a.s.l. The Aviation Color Code level remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

28 April-4 May 2010 Cite this Report

KVERT reported that during 22-30 April seismic activity from Kliuchevskoi was above background levels. Strombolian activity was noted and lava continued to flow down the flanks. Gas-and-steam plumes containing small amounts of ash were seen on 22 April. Similar plumes rose to an altitude of 7.3 km (23,900 ft) a.s.l. during 25-27 April, and drifted W and SW. Satellite imagery revealed a large daily thermal anomaly from the volcano. An ash plume drifted about 65 km W on 24 April, and gas-and-steam plumes drifted 55 km W and SW during 24-27 April. Based on analyses of satellite imagery, the Tokyo VAAC reported that on 3 May a possible eruption produced a plume that rose to an altitude of 4.9 km (16,000 ft) a.s.l. and drifted W. The Aviation Color Code level remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

21 April-27 April 2010 Cite this Report

KVERT reported that during 16-23 April seismic activity from Kliuchevskoi was above background levels. Strombolian activity was noted and lava continued to flow down the flanks. Gas-and-steam plumes rose to an altitude of 5.7 km (18,700 ft) a.s.l. Satellite imagery revealed a large daily thermal anomaly from the volcano, and ash plumes that drifted about 45 km S on 18 April. Gas-and-steam plumes drifted 90-100 km E on 20 and 21 April. Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 27 April an ash plume rose to an altitude of 7.9 km (26,000 ft) a.s.l. and drifted W. The Aviation Color Code level remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

14 April-20 April 2010 Cite this Report

KVERT reported that during 9-15 April seismic activity from Kliuchevskoi was above background levels. Strombolian activity periodically ejected material 200 m above the crater and lava continued to flow down the flanks. Satellite imagery revealed a large daily thermal anomaly from the volcano, and gas-and-steam plumes that drifted about 85 km NE on 9 April. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 April-13 April 2010 Cite this Report

KVERT reported that during 2-9 April seismic activity from Kliuchevskoi was above background levels. Strombolian activity periodically ejected material 200 m above the crater and lava continued to flow down the flanks. Satellite imagery revealed a large daily thermal anomaly from the volcano, and gas-and-steam plumes that drifted 30-180 km NNE. On 7 April, gas-and-steam plumes containing small amounts of ash rose to an altitude of 6.3 km (20,700 ft) a.s.l. The next day, a diffuse ash plume drifted 55-60 km NE. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 March-6 April 2010 Cite this Report

KVERT reported that during 26 March-2 April seismic activity from Kliuchevskoi was above background levels, and gas-and-steam plumes containing small amounts of ash were sometimes seen rising to an altitude of 5.3 km (17,400 ft) a.s.l. Strombolian activity ejected material 300 m above the crater and lava continued to flow down the flanks. Satellite imagery revealed a large daily thermal anomaly from the volcano, and gas-and-steam plumes that drifted about 70 km E on 30 March. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 March-30 March 2010 Cite this Report

KVERT reported that during 19-29 March seismic activity from Kliuchevskoi was above background levels. Strombolian activity ejected material 100-300 m above the crater and lava continued to flow down the flanks. Satellite imagery revealed a large daily thermal anomaly from the volcano, and gas-and-steam plumes that drifted over 80 km E during 18-20 March. Ash plumes seen in satellite imagery drifted about 75 km NE on 21 and 24 March. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 March-23 March 2010 Cite this Report

KVERT reported that during 12-19 March seismic activity from Kliuchevskoi was above background levels. Strombolian activity ejected material 200 m above the crater and lava continued to flow down the flanks. Gas-and-steam plumes rose to altitudes of 5 km (16,400 ft) a.s.l. during 12 and 15-16 March. Satellite imagery revealed a large daily thermal anomaly at the volcano. Based on information from KVERT, the Tokyo VAAC reported that on 21 March an ash plume rose to an altitude of 4.9 km (16,000 ft) a.s.l. and drifted NE. The Aviation Color Code level remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

10 March-16 March 2010 Cite this Report

KVERT reported that during 5-12 March seismic activity from Kliuchevskoi was above background levels. Strombolian activity ejected material 300 m above the crater. Gas-and-steam plumes rose to altitudes of 5-6.8 km (16,000-22,000 ft) a.s.l. and were occasionally seen on satellite imagery drifting 80 km E. On 4 March new lava flows traveled down the S and NE flanks. A satellite image from 9 March showed that the S-flank lava flow was about 1.3 km long. Phreatic explosions sometimes occurred from the fronts of the lava flows. Satellite imagery also revealed a large daily thermal anomaly at the volcano. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 March-9 March 2010 Cite this Report

KVERT reported that during 26 February-5 March seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 300 m above the crater, and phreatic explosions occurred from the fronts of the lava flows. Steam-and-gas plumes rose to an altitude of 6.8 km (22,300 ft) a.s.l. most days, and on 3 March one drifted 50 km NE. Satellite imagery revealed a large daily thermal anomaly from the volcano. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 February-2 March 2010 Cite this Report

KVERT reported that during 19-26 February seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 300 m above the crater, and phreatic explosions occurred from the fronts of the lava flows. Satellite imagery revealed a large daily thermal anomaly at the volcano and gas-and-steam plumes that drifted 90 km NNW on 23 February and 25 km ESE the next day. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 February-23 February 2010 Cite this Report

KVERT reported that during 12-19 February seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 200 m above the crater, and phreatic explosions occurred from the front of the lava flow. Satellite imagery revealed a large daily thermal anomaly at the volcano and gas-and-steam plumes that drifted over 240 km NE. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 February-16 February 2010 Cite this Report

KVERT reported that during 5-12 February seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 300 m above the crater. Steam plumes rose to an altitude of 6 km (19,700 ft) a.s.l. on 8, 9, and 10 February, and were seen on satellite imagery drifting 65 km NE. Satellite imagery also revealed a large daily thermal anomaly at the volcano. The Aviation Color Code level remained at Orange. Based on information from KVERT and analyses of satellite imagery, the Tokyo VAAC reported that on 13 February an ash plume rose to an altitude of 6.4 km (21,000 ft) a.s.l. and drifted NW.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

3 February-9 February 2010 Cite this Report

KVERT reported that during 29 January-5 February seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 300 m above the crater, and phreatic explosions occurred from the front of the lava flow. Satellite imagery revealed a large daily thermal anomaly at the volcano. On 30 and 31 January, gas-and-steam plumes rose to an altitude of 6.2 km (20,300 ft) a.s.l. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 January-2 February 2010 Cite this Report

KVERT reported that during 22-29 January seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 200 m above the crater, and phreatic explosions occurred from the front of the lava flow. Satellite imagery revealed a large daily thermal anomaly at the volcano. Ashfall was reported in Klyuchi, about 30 km to the NE, on 22 January. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 January-26 January 2010 Cite this Report

KVERT reported that during 15-22 January seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material 300 m above the crater. Phreatic explosions from the front of the lava flow ejected material that rose to altitudes of 4.5-8 km (14,800-26,200 ft) a.s.l. Satellite imagery also revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange. Based on information from the Yelizovo Airport (UHPP) and analyses of satellite imagery, the Tokyo VAAC reported that during 22-23 January ash plumes rose to altitudes of 7-10.1 km (23,000-33,000 ft) a.s.l. and drifted NE.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

13 January-19 January 2010 Cite this Report

KVERT reported that during 8-15 January seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the NW flank. Strombolian activity periodically ejected material above the crater. Phreatic explosions were seen from the front of the lava flow, which was about 1.2 km in length. Satellite imagery also revealed a large daily thermal anomaly at the volcano. During 12-14 January, gas-and-steam plumes rose to an altitude of 6.8 km (22,300 ft) a.s.l. and drifted E. The Level of Aviation Color Code remained at Orange. Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 18 January an ash plume rose to an altitude of 9 km (30,000 ft) a.s.l. and drifted N.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

6 January-12 January 2010 Cite this Report

KVERT reported that during 1-8 January seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity periodically ejected material 500 m above the crater. A new lava flow seen on the NW flank likely began during 2-3 January. On 5 January two lava flows, on the ESE flank and NW flanks, were seen in satellite imagery. Satellite imagery also revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 December-5 January 2010 Cite this Report

KVERT reported that during 24-31 December seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity ejected material 500 m above the crater. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 December-29 December 2009 Cite this Report

KVERT reported that during 18-25 December seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity ejected material 300 m above the crater. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 December-22 December 2009 Cite this Report

KVERT reported that during 11-21 December seismic activity from Kliuchevskoi was above background levels. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 December-15 December 2009 Cite this Report

KVERT reported that during 4-11 December seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity ejected tephra 200-300 m above the crater. Gas-and-steam plumes containing small amounts of ash rose to an altitude of 6.3 km (20,700 ft) a.s.l. and drifted E during 5-9 December. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 December-8 December 2009 Cite this Report

KVERT reported that during 27 November-4 December seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity ejected tephra 300 m above the crater. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 November-1 December 2009 Cite this Report

KVERT reported that during 20-27 November seismic activity from Kliuchevskoi was above background levels and lava continued to flow down the ESE flank. Strombolian activity ejected tephra 300 m above the crater during 21-25 November. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 November-24 November 2009 Cite this Report

KVERT reported that during 13-20 November seismic activity from Kliuchevskoi was above background levels. Strombolian activity ejected tephra 200 m above the crater during 13-15 November. On 14 November, a new lava flow traveled 500 m down the ESE flank. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 November-17 November 2009 Cite this Report

KVERT reported that during 6-13 November seismic activity from Kliuchevskoi was above background levels. Strombolian activity ejected tephra 300 m above the crater on 5, 7, and 10 November. Satellite imagery revealed a large daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 November-10 November 2009 Cite this Report

KVERT reported that during 30 October-6 November seismic activity from Kliuchevskoi was above background levels. Strombolian activity ejected tephra 300 m above the crater and fumarolic activity was occasionally noted. Satellite imagery revealed a daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 October-3 November 2009 Cite this Report

KVERT reported that during 23-30 October seismic activity from Kliuchevskoi was above background levels; tremor increased on 26 October. Strombolian activity ejected tephra 200 m above the crater and fumarolic activity was occasionally noted. Satellite imagery revealed a daily thermal anomaly at the volcano. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 October-27 October 2009 Cite this Report

KVERT reported that during 16-23 October seismic activity from Kliuchevskoi was above background levels. Satellite imagery revealed a daily thermal anomaly at the volcano. During 16 and 18-22 October, Strombolian activity ejected tephra 500 m above the crater and fumarolic plumes were noted. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 October-20 October 2009 Cite this Report

KVERT reported that during 9-16 October seismic activity from Kliuchevskoi was above background levels and weak tremor was detected. Satellite imagery revealed a daily thermal anomaly at the volcano. On 11 October, Strombolian activity ejected tephra 200 m above the crater. Fumarolic plumes containing small amounts of ash rose to an altitude of 5.7 km (19,700 ft) a.s.l. The Level of Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 October-13 October 2009 Cite this Report

KVERT reported that during 2-9 October seismic activity from Kliuchevskoi was above background levels; many earthquakes and weak tremor were detected. Satellite imagery revealed a weak thermal anomaly over the volcano. During 2-3 October, Strombolian eruptions sent tephra 70-100 m above the crater and fumarolic activity was noted. On 7 October a fumarolic plume containing some ash rose to an altitude of 5.7 km (19,700 ft) a.s.l. The Level of Aviation Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 September-6 October 2009 Cite this Report

KVERT reported that during 25 September-2 October seismic activity from Kliuchevskoi was slightly above background levels and weak tremor was detected. Satellite imagery revealed a weak thermal anomaly over the volcano. Strombolian activity ejected tephra 70-100 m above the crater during 28-30 September. The Level of Aviation Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 September-22 September 2009 Cite this Report

KVERT reported that although seismic activity from Kliuchevskoi did not exceed background levels during 11-18 September, weak tremor was detected. Satellite imagery revealed a weak thermal anomaly over the volcano from 13 to 17 September. Strombolian activity that ejected tephra 70 m above the crater was seen at night on 16 and 17 September. The Level of Aviation Color Code was raised to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 August-18 August 2009 Cite this Report

Based on analyses of satellite imagery and information from KEMSD, the Tokyo VAAC reported that on 17 August an eruption from Kliuchevskoi produced a plume that rose to an altitude of 5.2 km (17,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)

29 July-4 August 2009 Cite this Report

On 2 August, KVERT reported that seismic activity from Kliuchevskoi had gradually increased since 30 July, and continuous seismic tremor was detected. A strong thermal anomaly was seen in satellite imagery at night. The Level of Concern Color Code was raised to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 June-16 June 2009 Cite this Report

On 11 June, KVERT reported that seismic activity from Kliuchevskoi had remained at background levels since 12 May. Weak intermittent volcanic tremor and fumarolic activity continued to be detected. The Level of Concern Color was lowered to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 April-21 April 2009 Cite this Report

KVERT reported that seismic activity from Kliuchevskoi was slightly above background levels on 11 April and at background levels the other days during 12-17 April. Satellite imagery revealed gas-and-ash plumes that drifted 90 km NE on 9 and 10 April, and a weak thermal anomaly over the volcano on 14 April. Fumarolic activity was seen on 15 and 16 April. The Level of Concern Color remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 April-14 April 2009 Cite this Report

KVERT reported that fumarolic activity from Kliuchevskoi was observed during 3-10 April. Satellite imagery indicated a thermal anomaly over the volcano on 5 and 6 April, and weak volcanic tremor was detected during 5-8 April. Based on analysis of satellite imagery, the Tokyo VAAC reported that a possible eruption on 9 April produced a plume that rose to an altitude of 4.9 km (16,000 ft) a.s.l. and drifted NE. Imagery later indicated that any ash that may have been present had dissipated. On 11 April, imagery again indicated a possible eruption; any resultant ash plumes had dissipated by a few hours later. The Level of Concern Color remained at Yellow.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

28 January-3 February 2009 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was at background levels during 22-24 and 28 January, and above background levels during 25-27 January. Diffuse steam-and-gas plumes were noted. Analysis of satellite imagery revealed a weak daily thermal anomaly in the crater. The Level of Concern Color Code was lowered to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 January-27 January 2009 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 15-18 and 26-27 January and at background levels during 19-21 January. Diffuse steam-and-gas plumes were noted. The magnitude of volcanic tremor rapidly decreased during 16-21 January. Analysis of satellite imagery revealed a weak daily thermal anomaly in the crater. The Level of Concern Color Code was lowered to Yellow. Strombolian activity in the summit crater was noted on 26 January. Ash plumes were seen drifting NE and E at altitudes of 5.3 km (17,400 ft) a.s.l. during 26-27 January, and were detected on satellite imagery drifting 80 km E at an altitude of 5.2 km (17,000 ft) a.s.l. on 27 January. The Level of Concern Color Code was raised to Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

14 January-20 January 2009 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 9-16 January. Gas-and-steam plumes rose to an altitude of 6.8 km (22,300 ft) a.s.l. and drifted about 50 km S and E. Strombolian activity was noted on 9 and 10 January. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater and gas-and-steam plumes that drifted 70 km W on 12 January. The Level of Concern Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 January-13 January 2009 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 1-9 January. Strombolian activity and lava effusion on the NW flank continued. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. Ashfall was reported in Kozyrevsk village (about 50 km W) on 1 January. Ash plumes drifted 60 km N on 1 January and 35 km SW on 2 January.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 December-6 January 2009 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels 26 December-2 January. Strombolian activity was noted on 25 and 27 December, and lava effusion on the NW flank continued. On 25 December gas-and-steam plumes containing ash rose to an altitude of 5.5 km (18,000 ft) a.s.l. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. Ash plumes drifted 250 km NE during 25-26 December. On 27 December ashfall was reported in Kozyrevsk village. The Tokyo VAAC reported that on 2 January ash plumes were continuously observed on satellite imagery.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

24 December-30 December 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 19-26 December. Gas-and-steam plumes containing ash rose to an altitude of 7 km (23,000 ft) a.s.l. during 20-24 December. Lava effusion on the NW flank continued and Strombolian activity was noted during 21-25 December. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. Ash plumes drifted 270 km E and NE during 20-25 December.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 December-23 December 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 12-19 December. Strombolian activity was noted on 12, 13, 14, and 16 December, and lava effusion on the NW flank continued. Gas-and-steam plumes containing ash rose to an altitude of 8 km (26,200 ft) a.s.l. during 12-14 and 18 December. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. Ash plumes rose to altitudes of 4-8 km (13,100-26,200 ft) a.s.l. and drifted 500 km E, NE, and SE during 12-14 and 16-18 December.

Based on analysis of satellite imagery, the Tokyo VAAC reported that on 21 December a possible eruption produced a plume to an altitude of 5.2 km (17,000 ft) a.s.l. The plumes drifted N. Ash emissions continued the next day. An eruption on 23 December produced an ash plume to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted NE.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

10 December-16 December 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 5-12 December. Strombolian activity ejected bombs 500 m above the crater and lava effusion on the NW flank continued. Phreatic bursts occurred where the lava flow front contacted the Erman Glacier. On 6 and 9 December, ashfall was reported in Klyuchi, about 30 km to the NE. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. Gas-and-steam plumes containing small amounts of ash rose to altitudes of 5-6 km (16,400-19,700 ft) a.s.l. and drifted more than 300 km E. During 8-10 December, ash plumes rose to altitudes of 7.5-8 km (24,600-26,200 ft) a.s.l. and drifted about 700 km E. The Level of Concern Color Code remained Orange.

Based on information from KVERT and analysis of satellite imagery, the Tokyo VAAC reported that during 13-15 December eruptions ash produced plumes to altitudes of 5.2-8.2 km (17,000-27,000 ft) a.s.l. Plumes drifted E and NE.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

3 December-9 December 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 28 November-10 December; Strombolian activity ejected bombs 500 m above the crater and lava effusion on the NW flank continued. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater. During 27-29 November, and 2 and 4 December, gas-and-steam plumes with little ash content rose to altitudes of 6-6.2 km (19,700-20,300 ft) a.s.l. and drifted 40-115 km NE, E, SE, and SW. During 4-5 December, the ash content in plumes increased. On 8 December, phreatic bursts occurred where the lava flow front contacted the Erman Glacier. On 9 December, a 50-km-wide ash plume drifted about 550 km ENE. The Level of Concern Color Code was raised to Red. KVERT warned that the activity was dangerous for international and low-flying aircraft. On 10 December, the Level of Concern Color Code was lowered back to Orange because explosive activity decreased. A gas-and-steam plume with a small amount of ash drifted NE.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 November-2 December 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 21-28 November; Strombolian activity and lava effusion continued. On 21 November, a lava flow traveled 1.5-1.8 km down the NW flank. Gas-and-steam plumes drifted 80 km NW on 24 November and 20-40 km SE during 25-26 November. Gas-and-steam plumes containing slight amounts of ash rose to altitudes of 5.3-5.5 km (17,400-18,000 ft) a.s.l. during 26-27 November. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater during 21-28 November. The Level of Concern Color Code remained Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 November-25 November 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 14-21 November and Strombolian activity continued. Video and visual observations showed that during 13-17 November gas-and-steam plumes containing a small amount of ash rose to an altitude of 5.3 km (17,400 ft) a.s.l. On 17 November, "bursting" sounds from the volcano were heard in Klyuchi, about 30 km to the NE. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater during 14-21 November. On 22 November a lava flow traveled 1.5-1.8 km down the NW flank. The Level of Concern Color Code remained Orange. [Correction: a lava flow traveled down the NW flank on 21 November.]

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 November-18 November 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 7-13 November. Video and visual observations showed that during 8 and 10-12 November gas-and-steam plumes that contained a small amount of ash rose to an altitude of 5.1 km (16,700 ft) a.s.l. Analysis of satellite imagery revealed a daily thermal anomaly in the crater. The Level of Concern Color Code remained Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 November-11 November 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 31 October-7 November. Video and visual observations showed that during 31 October, and 1-2 and 5-6 November, gas-and-steam plumes that contained a small amount of ash rose to an altitude of 5.2 km (17,100 ft) a.s.l. On 3 and 4 November, "bursting" sounds from the volcano were heard in Klyuchi, about 30 km to the NE. Analysis of satellite imagery revealed a daily thermal anomaly in the crater. The Level of Concern Color Code remained Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 October-4 November 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 24-31 October. Video and visual observations showed fumarolic activity during 24-25 and 28-30 October. "Bursting" sounds from the volcano were heard in Klyuchi, about 30 km to the NE. Analysis of satellite imagery revealed a daily thermal anomaly in the crater. The Level of Concern Color Code remained Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 October-28 October 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 17-24 October. Fumarolic activity was noted during 17-19 and 22-23 October by video and visual observations. Analysis of satellite imagery revealed a daily thermal anomaly in the crater. The Level of Concern Color Code remained Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 October-21 October 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was above background levels during 10-17 October. Fumarolic activity was noted during 10-11 and 13-16 October. Observers in Klyuchi, about 30 km to the NE, reported nighttime incandescence in the crater on 13 and 14 October. Analysis of satellite imagery revealed a thermal anomaly in the crater during 10-11 and 13-15 October. The Level of Concern Color Code remained Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 October-14 October 2008 Cite this Report

KVERT reported that fumarolic activity from Kliuchevskoi was seen during 2-6 and 8-9 October. During approximately 4-9 October analysis of satellite imagery revealed a thermal anomaly in the crater; seismic activity was above background levels. On 8 October after KVERT staff detected Strombolian activity in the summit crater the level of Concern Color Code was raised to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 August-12 August 2008 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi had slowly increased since June and was slightly above background levels during 1-8 August. Observations of satellite imagery revealed that the size and intensity of a thermal anomaly in the crater increased. On 8 August, the level of Concern Color Code was raised to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 August-21 August 2007 Cite this Report

On 17 August, KVERT reported that seismic activity at Kliuchevskoi was at background levels during the past five weeks, and ash plumes had not been noted for the last four weeks. Satellite imagery showed a thermal anomaly on 11 August. The Level of Concern Color Code was lowered from Yellow to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 July-24 July 2007 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi was at background levels during 13-20 July. Based on observations of satellite imagery, ash plumes drifted E on 13 July and a thermal anomaly in the crater was noted during 13-20 July. Ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted SE and E during 13-15 July, according to video and visual observations. Gas-and-steam plumes were observed on 12, 16, and 18 July. The Level of Concern Color Code was lowered from Orange to Yellow due to a decrease in seismicity and an absence of ash plumes during 17-20 July.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 July-17 July 2007 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi had decreased, but remained above background levels during 6-13 July. Ash plumes were visible on satellite imagery drifting NE and NW during 5-11 July. Plumes rose to estimated altitudes of 5-6.5 km (16,400-21,300 ft) a.s.l. based on atmospheric profiles. Based on video data, ash plumes rose to an altitude of 7 km (23,000 ft) a.s.l. during 9-11 July. The Level of Concern Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 July-10 July 2007 Cite this Report

KVERT reported that seismic activity at Kliuchevskoi had decreased, but remained above background levels during 29 June-6 July. Based on seismic interpretation, ash plumes possibly rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. On 4 July, the Level of Concern Color Code was lowered from Red to Orange. During 2-5 July, ash plumes rose to estimated altitudes of 5-6 km (16,400-20,000 ft) a.s.l. based on atmospheric profiles. Plumes were visible on satellite imagery drifting NNW, W, and SE.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 June-3 July 2007 Cite this Report

KVERT reported that during 22-29 June, seismic activity at Kliuchevskoi continued above background levels. Based on atmospheric profiles, ash plumes rose to estimated altitudes of 4.5-9.5 km (14,800-31,200 ft) a.s.l. and drifted in multiple directions during 21-24 and 28 June. A thermal anomaly continued to be detected in the crater on satellite imagery during 22-23 and 26-27 June. On 28 June, seismicity increased and indicated that an ash plume rose to an altitude of 9 km (30,000 ft) a.s.l. The Level of Concern Color Code was raised to Red.

Ash plumes were visible on satellite imagery drifting E more than 2,000 km on 29 June and drifting SW more than 900 km on 30 June. Based on video and visual observations, ash plumes rose to an altitude greater than 10 km (32,000 ft) a.s.l. and drifted W on 30 June. Ash plumes were visible on satellite imagery drifting E. On 1 July, plumes drifted N.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 June-26 June 2007 Cite this Report

KVERT reported that during 15-22 June, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Based on video and visual observations, ash plumes rose to an altitude of 5 km (16,400 ft) a.s.l. and drifted NE on 15 June. Clouds inhibited observations on other days. Plumes were seen drifting N, W, and S on satellite imagery during 15-22 June.

A large ash cloud, about 300 km in diameter, was observed near Yelizovo airport during 20-21 June. Based on atmospheric profiles, the plumes rose to estimated altitudes of 6.5-9.5 km (21,300-31,200 ft) a.s.l. and drifted SE.

On 25 June, KVERT reported that seismic activity decreased during 22-24 June. Ash plumes were visible on satellite imagery drifting multiple directions. The plumes rose to estimated altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l. based on atmospheric profiles. A thermal anomaly continued to be detected in the crater. The Level of Concern Color Code was lowered to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 June-19 June 2007 Cite this Report

KVERT reported that during 8-15 June, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Strombolian and Vulcanian activity at the summit crater, lava flows, and phreatic bursts at the SE flank of the volcano were observed on 8 and 13 June. Based on video and visual observations, ash plumes rose to altitudes of 7 km (23,000 ft) a.s.l. during 8-10 and 13 June and drifted E, SE, and NW. Ash plumes were visible on satellite imagery drifting multiple directions during 8-15 June.

KVERT reported that seismicity increased on 19 June at 1010. Beginning at 0400 on 20 June, ash plumes were visible on satellite imagery, drifting W. Based on atmospheric profiles, plume altitudes rose to an altitude of 6.5-7.5 km (21,300-24,600 ft) a.s.l. Ashfall was reported from Kozyrevsk village. The Level of Concern Color Code was raised to Red.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 June-12 June 2007 Cite this Report

KVERT reported that during 1-8 June, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Video and visual observations during 1-4 June indicated Strombolian and Vulcanian eruptions at the summit crater. Lava flows generated phreatic bursts from places where hot lava interacted with ice on the NW and SE flanks. Ash plumes rose to altitudes of 7 km (23,000 ft) a.s.l. and drifted E and SE during 1-6 June. Plumes were seen on satellite imagery drifting E and S during 1-8 June. Based on information from KVERT, the Tokyo VAAC reported that an ash plume rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted NW on 12 June. The Level of Concern Color Code remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

30 May-5 June 2007 Cite this Report

KVERT reported on 1 June that the Level of Concern Color Code for Kliuchevskoi was lowered from Red to Orange. During 25 May-1 June, seismic activity continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. According to video data and visual observations on 27 and 31 May, there was Strombolian and Vulcanian activity at the summit crater, lava flows, and phreatic bursts on the NW flank from where lava interacted with ice. Ash plumes rose to altitudes of 5-7 km (16,000-26,200 ft) a.s.l. during 29-31 May and drifted in multiple directions. Strong phreatic bursts were seen from the front of a new lava flow from on the E flank on 31 May.

Based on information from KVERT, the Tokyo VAAC reported that ash emissions produced plumes on 2 and 5 June to an altitude of about 5.8 km (19,000 ft) a.s.l. Ash was not identified on satellite imagery. During 3-4 June, ash plumes to altitudes of 5.2-7 km (17,000-23,000 ft) a.s.l. were possibly identified on satellite imagery.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

23 May-29 May 2007 Cite this Report

KVERT reported that during 18-25 May, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. On 18 May, ashfall was reported from the town of Klyuchi, about 30 km to the NE. According to video data and visual observations, Vulcanian activity at the summit crater and phreatic bursts on the NW flank of the volcano were observed during 22-24 May. Ash plumes rose to 5-8 km (16,000-25,600 ft) a.s.l. and drifted SE. Plumes were visible on satellite imagery drifting N, NE, and SE during the reporting period. Clouds inhibited observation on other days. The Level of Concern Color Code remained at Red.

Based on satellite image observations and information from KVERT, the Tokyo VAAC reported that ash emissions produced possible plumes on 26 May to an altitude of 6.4 km (21,000 ft) a.s.l. and on 27 May to an altitude of 10.1 km (33,000 ft) a.s.l. Plumes drifted E, S, SW, and W. Ash plumes were also observed on satellite imagery during 28-29 May drifting S, SW, and W.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

16 May-22 May 2007 Cite this Report

KVERT reported that during 11-22 May, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. According to video data and visual observations, Vulcanian activity at the terminal crater and phreatic bursts at the NW flank of the volcano were observed on 11 and 16 May. Also on 11 and 16 May, ash plumes rose to 9.7 km (31,800 ft) a.s.l. and drifted E and NE, respectively. Clouds inhibited observation on other days. Ashfall was reported from the town of Klyuchi, about 30 km to the NE, during 11-12 and 16-17 May. KVERT raised the Level of Concern Color Code from Orange to Red on 17 May.

On 18 May, KVERT reported that deposits from a mudflow filled the Krivaya river. During 18-22 May, ash plumes rose to an altitude of 8.5 km (27,900 ft) a.s.l. Based on observations from satellite imagery, ash plumes drifted N, NE, NW, and E during 11-22 May.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 May-15 May 2007 Cite this Report

KVERT reported that during 4-11 May, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Lava flows continued to advance on the NW flank. Phreatic activity and ash plumes from lava-flow fronts were noted. Gas-and-steam plumes containing ash rose to altitudes of 6.7 km (22,000 ft) a.s.l. and drifted N during 4-7 May. Ash plumes were seen on satellite imagery drifting NE, NW, W, and E during the reporting period. Ashfall was reported on 4 May and explosions were heard during 3-6 May in the town of Klyuchi, about 30 km to the NE. Based on information from KEMSD and satellite imagery, the Tokyo VAAC reported that on 11 May ash plumes rose to altitudes of 7.6 km (25,000 ft) a.s.l. and drifted SE and E. On 12 May, the Anchorage VAAC reported that ash plumes were visible on satellite imagery. On 15 May, the Tokyo VAAC reported that an eruption plume was possibly seen on satellite imagery to an altitude of 5.2 km (17,000 ft) a.s.l. drifting N. The Level of Concern Color Code remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Anchorage Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

2 May-8 May 2007 Cite this Report

Based on observations and video data, KVERT reported that Strombolian activity occurred at Kliuchevskoi during 27 April-4 May. Seismic activity continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Mudflows and lava flows continued to advance on the NW flank. Phreatic activity and ash plumes from lava-flow fronts were noted. Gas-and-steam plumes containing ash rose to altitudes of 6.2 km (20,400 ft) a.s.l. during the reporting period and were visible on satellite imagery drifting S and SE. Based on information from KVERT, the Tokyo VAAC reported that ash plumes rose to an altitude of 5.2 (17,000 ft) a.s.l. and drifted NE on 3 May. According to a news article, an ash plume rose to altitudes of 5.3-5.5 km (17,400-18,000 ft) a.s.l. and drifted NE on 7 May. Ashfall was reported from the town of Klyuchi, about 30 km to the NE. The Level of Concern Color Code remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT); Itar-Tass News

25 April-1 May 2007 Cite this Report

During 20-27 April, KVERT reported that Strombolian activity occurred at Kliuchevskoi, based on observations and video data. Seismic activity continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Mudflows and lava flows continued to advance on the NW flank. Phreatic activity and ash plumes from lava-flow fronts were noted. Gas-and-steam plumes containing ash rose to altitudes of 7.2 km (23,600 ft) a.s.l. and were visible on satellite imagery drifting E and SE. Based on satellite imagery and information from KVERT, the Tokyo VAAC reported that ash plumes rose to an altitude of 5.2 (17,000 ft) a.s.l. and drifted E during 25-26 April. The Level of Concern Color Code remained at Orange.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT)

18 April-24 April 2007 Cite this Report

During 13-20 April, Strombolian activity occurred at Kliuchevskoi, based on observations and video data. Seismic activity continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Fumarolic activity intensified during 15 and 17-18 April. Gas-and-steam plumes possibly containing small amounts of ash rose to altitudes of 6.3-7.2 km (20,700-23,600 ft) a.s.l. during 15 and 17-18 April and drifted in multiple directions. Based on pilot reports, satellite imagery, and observations in the Petropavlovsk-Kamchatsky Flight Information Region (FIR), the Tokyo VAAC reported several E-drifting ash plumes. They rose to altitudes of 5.2 (17,000 ft) a.s.l. and 8.8 km (29,000 ft) on 18 and 22 April, respectively. On 24 April, KVERT reported mudflows and phreatic activity at lava flow fronts on the NW flank. Resultant ash plumes rose from the lava flow fronts to an altitude of 3.5 km (11,500 ft) a.s.l. The Level of Concern Color Code remained at Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Kamchatkan Volcanic Eruption Response Team (KVERT)

11 April-17 April 2007 Cite this Report

Seismic activity at Kliuchevskoi continued above background levels during 10-13 April. Based on observations and video data, lava flowed down the NW flank and Strombolian activity occurred at the crater. Everyday during 10-13 April a gas-and-steam plume possibly containing a small amount of ash rose to an altitude of 6.3 km (20,700 ft) a.s.l. and drifted E. A thermal anomaly in the crater was detected on satellite imagery during 10-12 April. The Level of Concern Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 April-10 April 2007 Cite this Report

Seismic activity at Kliuchevskoi continued at above background levels during 4-10 April. A gas-and-steam plume with a small amount of ash rose to an altitude of 5.3 km (17,400 ft) a.s.l. and drifted W and SW during 4-8 April. Strombolian activity was seen at the crater during 4-9 April. Based on observations and video data, lava was observed flowing down the NW flank on 9 April. A thermal anomaly in the crater was detected on satellite imagery during 2-10 April. The Level of Concern Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 March-3 April 2007 Cite this Report

Based on observation and video data, lava from Kliuchevskoi flowed down the NW flank on 29 March. On 31 March, lava bombs from Strombolian activity were projected about 100-200 m above the crater. According to a news article, lava flows are interacting with snow and ice and producing vapor plumes.

Sources: RIA Novosti; Kamchatkan Volcanic Eruption Response Team (KVERT)

21 March-27 March 2007 Cite this Report

Strombolian activity from Kliuchevskoi was observed during 16-18 February and 21-22 March. Lava bombs were ejected about 50-100 m above the crater. Clouds inhibited visual observations during most of February and March, but a thermal anomaly was detected on satellite imagery each day.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 February-27 February 2007 Cite this Report

Seismic activity at Kliuchevskoi continued at above background levels during 16-22 February. Based on observation and video data, gas-and-steam plumes rose to an altitude of 5.3 km (17,400 ft) a.s.l. and drifted E. These plumes possibly contained some ash. A thermal anomaly at the summit was seen on satellite imagery during 16-19 and 21 February. Based on information from KEMSD and satellite imagery, the Tokyo VAAC reported that eruption plumes possibly reached altitudes of 6.1 km (20,000 ft) a.s.l. and drifted E during 22-23 February.

According to a news article, ash particles up to 2 mm in diameter fell on the village of Klyuchi, about 40 km N on 26 February.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kamchatkan Volcanic Eruption Response Team (KVERT); RIA Novosti

14 February-20 February 2007 Cite this Report

Increased summit activity at Kliuchevskoi on 15 February led KVERT to raise the Concern Color Code from Yellow to Orange. Ash explosions and incandescence at the summit were observed. Strombolian explosions expelled bombs about 300 m above the crater. Based on video data and observations, gas-and-steam plumes with small amounts of ash rose to altitudes of 5.3 km (17,400 ft) a.s.l. and drifted SW. A thermal anomaly at the summit was seen on satellite imagery.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 December-19 December 2006 Cite this Report

On 19 December, KVERT reported that the Level of Concern Color Code for Kliuchevskoi was raised from Green to Yellow due to a slight increase in seismicity above background levels. Moderate fumarolic activity was noted from the crater. A thermal anomaly in the crater was detected on satellite imagery on 14, 15, and 18 December.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 November-8 November 2005 Cite this Report

Seismic activity at Kliuchevskoi was at background levels during the previous 3 weeks and no activity was observed on satellite imagery. Since there were no indications that an eruption was imminent at Kliuchevskoi, KVERT reduced the Concern Color Code from Yellow to Green on 4 November.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 September-20 September 2005 Cite this Report

An increase in seismicity at Kliuchevskoi during 9-16 September led KVERT to raise the Concern Color Code from Green to Yellow. The amplitude of volcanic tremor at the volcano increased. Weak gas-and-steam emissions and a thermal anomaly were visible on satellite imagery during the week.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 August-16 August 2005 Cite this Report

Seismic activity at Kliuchevskoi decreased to background levels during 5-12 August, so KVERT reduced the Concern Color Code from Yellow to Green (the lowest level). Only weak fumarolic activity was observed at the volcano.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 August-9 August 2005 Cite this Report

Seismic activity at Kliuchevskoi decreased to the background levels. Fumarolic activity was observed the week of 3-9 August.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 July-2 August 2005 Cite this Report

A decrease in volcanic tremor at Kliuchevskoi during the end of the week of 22-29 July led KVERT to reduce the Concern Color Code from Orange to Yellow. On 22 July, weak ash-and-gas plumes rose to ~100 m above the crater (16,200 ft a.s.l.).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 July-26 July 2005 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 15-22 July, with spasmodic volcanic tremor and shallow earthquakes occurring. A gas-and-steam plume rose ~5.5 km above the crater (~33,900 ft a.s.l.) on 19 July. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 July-19 July 2005 Cite this Report

Seismicity increased to above background levels at Kliuchevskoi during 8-15 July. Gas-and-steam plumes rose to low levels above the volcano during 8, and 10-13 July. KVERT raised the Concern Color Code from Yellow to Orange around 15 July.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 May-17 May 2005 Cite this Report

Seismic activity was slightly above background levels until 7 May and at background levels on 8-9 May. Weak gas-and-steam plumes were seen rising up to 100 m above the crater and extended E on 6 May and for 5 km to the SE on 7 May. Clouds obscured the volcano at other times. A weak thermal anomaly was detected in satellite data during 6-9 May. Kliuchevskoi remained at Concern Color Code Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 April-19 April 2005 Cite this Report

Seismic activity at Kliuchevskoi decreased during 8-15 April, but remained above background levels. Gas-and-steam plumes rose to low levels above the crater. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 April-12 April 2005 Cite this Report

Seismic activity was above background levels during 1-8 April, with a large number of shallow earthquakes occurring. Ash-and-gas plumes rose to 1 km above the crater (19,100 ft. a.s.l.). Eruptive and seismic activity decreased significantly on 7 April. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 March-5 April 2005 Cite this Report

Seismic activity was above background levels at Kliuchevskoi during 25 March to 1 April. Ash-and-gas plumes rose 2.5-3 km above the crater (24,100-25,700 ft a.s.l.). Incandescence was observed above the summit crater on 28 March. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 March-29 March 2005 Cite this Report

On 24 March KVERT raised the Concern Color Code at Kliuchevskoi to Red (the highest level) due to an increase in seismic and volcanic activity. According to visual and video data, a gas-and-steam plume containing ash rose to ~7.5 km (24,600 ft) a.s.l. on 22 March, and ~8.5 km (~27,900 ft) a.s.l. on 23 March, extending NW. Ash fell in the town of Kluchi during 23-24 March. According to data from AMC Yelizovo, an ash plume that rose to ~7 km (~23,000 ft.) a.s.l. and extended 70-80 km (44-50 mi) to the NW was observed by pilots on 23 March.

During about 27-28 March seismic activity at Kliuchevskoi decreased, leading KVERT to reduce the Concern Color Code to Orange. According to visual and video data, a gas-and-steam plume containing some ash rose ~200 m above the crater (~16,500 ft a.s.l.) and extended W during 27-28 March.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 March-22 March 2005 Cite this Report

Eruptive activity continued at Kliuchevskoi during 11-18 March. Strombolian explosions occurred intermittently from a cinder cone in the summit crater. Lava flows extended from this cinder cone down the NW flank of the volcano. Occasional vigorous explosions from the summit crater and along the path of the lava flow produced ash plumes that reached as high as 7-8 km (23,000-26,200 ft) a.s.l. and drifted many tens or hundreds of kilometers downwind.

Seismicity was above background levels at Kliuchevskoi during the report period. Ash-and-gas plumes rose to 3.2 km above the crater (~26,300 ft a.s.l.) on 11-12 March. Ash fell in the town of Kozyrevsk on 11 March. Strombolian bursts rose 500-1,000 m (1,600- 3,300 ft) above the summit crater. On 15 March two lava flows were observed on the NW slope of the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 March-8 March 2005 Cite this Report

Moderate seismic and volcanic activity continued at Kliuchevskoi during 24 February to 4 March. On 24 February a lava flow continued to travel down the Krestovsky channel on the volcano's NW flank. Strombolian activity occurred during the report period, with plumes rising to ~1 km above the volcano. Ash fell in the village of Icha on 26 February, and in Kozyrevsk on 1 March. Ash plumes were visible on satellite imagery on several days. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 February-22 February 2005 Cite this Report

During 11-18 February, seismicity was above background levels at Kliuchevskoi, with a large number of shallow earthquakes occurring daily. Ash plumes rose ~3 km above the volcano's crater during 12-14 February. Phreatic bursts, which occurred when lava flows contacted a glacier, were seen on 12 and 13 February. During 12-16 February, volcanic bombs were hurled 300-500 m above the crater, Strombolian activity occurred in the crater, and lava traveled into Krestovsky channel on the volcano's NW flank. During a flight on 16 February, a mudflow was seen extending 27 km. According to a news report, a lava flow from Kliuchevskoi melted a large section of Ehrman glacier. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 February-15 February 2005 Cite this Report

During 4-11 February, seismicity was above background levels at Kliuchevskoi and ash plumes rose above the volcano. On 6, 8, and 9 February, ash plumes rose ~2.5 km above the volcano's crater. Gas-and-steam plumes rose to ~3 km during 6-9 February. A cinder cone was noted in the volcano's crater on 6 February. Fresh ash deposits were seen on the SW flank of Ushkovsky volcano (NW of Kliuchevskoi) on 7 February, and in the town of Kluchi on 9 February.

During 31 January to 9 February, Strombolian activity occurred in the terminal crater of Kliuchevskoi and a lava flow traveled into Krestovsky channel on the volcano's NW flank. Phreatic bursts occurred in this channel when a lava flow contacted glaciers during 6-9 February. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 February-8 February 2005 Cite this Report

On 1 February around 1000, a mudflow traveled ~6 km down Kliuchevskoi's NW flank into the Kruten'kaya River. The mudflow reached a height of a few meters and trees were covered with mud to about 1.5 m. Large blocks and trees were carried by the flow. A possible lava flow traveled down Krestovsky channel on the volcano's flank on 31 January.

During 28 January to 4 February, seismicity at Kliuchevskoi was above background levels, with a large number of shallow earthquakes occurring daily. Gas-and-steam plumes rose to ~1 km above the volcano's crater and drifted SW on 29 January and NW on January 31. A small amount of ash fell in Klyuchi on 31 January. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 January-1 February 2005 Cite this Report

Strombolian activity occurred at Kliuchevskoi during 20-23 and 27 January. Explosions sent volcanic bombs 50-300 m above the crater on several nights. Gas-and-steam plumes rose to a maximum height of 1.5 km above the crater. On 21 January a gas-and-steam plume with small amounts of ash extended as far as 23 km NE of the volcano. During 21-28 January seismicity was above background levels, with a large number of shallow earthquakes recorded daily. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 January-25 January 2005 Cite this Report

During 14-21 January, seismicity was above background levels at Kliuchevskoi and the total number of shallow earthquakes continued to increase. Gas-and-steam plumes rose to ~800 m above the lava dome. Incandescence was visible in the volcano's crater during several nights. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 January-18 January 2005 Cite this Report

KVERT raised the Concern Color Code at Kliuchevskoi from Green to Yellow on 14 January as seismic activity at the volcano increased. On 12 January, around 21 shallow earthquakes of M=1.0-1.7 and weak volcanic tremor were recorded. According to visual observations, weak gas-and-steam plumes were noted during 6-8 and 12 January. The plumes extended E from the volcano on 7 January and SW for 5 km from the volcano on 12 January.

KVERT again raised the Concern Color Code from Yellow to Orange as seismic activity increased significantly. During 13-14 January, 15 shallow earthquakes of M > 1.25 were recorded, along with an increase in the amplitude of volcanic tremor. Visual observations on 14 January noted a weak gas-and-steam plume that extended N from the volcano. Satellite data showed a bright thermal anomaly over the summit on 15 January.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 November-30 November 2004 Cite this Report

Around 26 November, the Concern Color Code at Kluichevskoi was reduced from Yellow to Green, the lowest level. During 19-26 November, seismicity was at background levels. Gas-and-steam plumes were seen up to 5 km a.s.l. on 24 November and weak fumarolic activity was observed on several days.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 September-21 September 2004 Cite this Report

Seismic activity was at background levels this week. About 102 earthquakes (M 1.0-2.3) at a depth up to 30 km were recorded this week. A strong ash-and-gas plume rose up to 7 km a.s.l. on 15 September. Weak fumarolic activity was observed the next day. Kliuchevskoi remained at Concern Color Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 March-9 March 2004 Cite this Report

KVERT reduced the Concern Color Code at Kliuchevskoi from Orange to Yellow during 27 February to 5 March. Seismicity was slightly above background levels during 26-27 February and at background levels the rest of the week. Several shallow earthquakes up to M 2.2 were recorded, along with spasmodic tremor. Gas-and-steam plumes rose to low levels.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 February-2 March 2004 Cite this Report

Seismicity at Kliuchevskoi was above background levels during 20-27 February, with ~160 M 1.25-1.75 earthquakes and 12 M 1.25-2.25 earthquakes occurring at depths of 3-7 km beneath the volcano. Gas-and-steam plumes rose to ~700 m above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 February-24 February 2004 Cite this Report

During 13-20 February seismicity was above background levels at Kliuchevskoi, with 135 earthquakes of M 1.25-1.7 and 1-6 earthquakes up to M 1.85 occurring daily at depths of 3-6 km beneath the volcano. Gas-and-steam plumes rose to ~1 km above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 February-17 February 2004 Cite this Report

During 6-13 February, seismicity was above background levels at Kliuchevskoi, with ~225 shallow M 1.25-2 earthquakes recorded during the week. The amount of spasmodic tremor decreased during the report period. In addition, gas-and-steam plumes rose ~700 m above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 February-10 February 2004 Cite this Report

During 30 January to 6 February, seismicity was above background levels at Kliuchevskoi, with ~430 strong shallow earthquakes recorded during the week and gas-and-steam plumes rising to low levels. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 January-3 February 2004 Cite this Report

During 23-30 January, seismicity was above background levels at Kliuchevskoi, with ~130 shallow M 1.9-2.3 earthquakes and a large number of weaker events occurring. Probable Strombolian activity was seen at the volcano on the evenings of 24 and 26 January. Gas-and-steam plumes rose to ~3 km above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 January-27 January 2004 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 16-23 January, with ~130 shallow M 1.9-2.3 earthquakes and a large number of weaker events recorded. Ash explosions produced low-level plumes on 15 January that drifted NW. According to the Tokyo VAAC, an eruption on 24 January produced an ash plume to ~2.7 km a.s.l. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 January-20 January 2004 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 9-16 January, with ~175 shallow M 1.9-2.5 earthquakes and a large number of weaker events recorded. Ash explosions rose 0.5-1 km above the volcano during 11-13 January. Strombolian activity was observed at the central crater during 11-12 January. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 January-13 January 2004 Cite this Report

During 2-9 January, seismicity was above background levels at Kliuchevskoi, with ~115 shallow M1.9-2.3 earthquakes and a large number of weaker events recorded. On 2 January an ash explosion rose slightly above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 December-6 January 2004 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 26 December to 2 January, with ~33 shallow M 1.9-2.2 earthquakes and a large number of weaker events recorded. Gas-and-steam plumes rose to low levels above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 December-30 December 2003 Cite this Report

During 19-26 December, seismicity at Kliuchevskoi was above background levels, with the occurrence of ~135 large shallow earthquakes between M 1.9-2.3 and a large number of weaker events. Gas-and-steam plumes rose to low levels above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 December-23 December 2003 Cite this Report

At Kliuchevskoi seismicity was above background levels during 12-19 December, with ~150 shallow M 1.75-2.25 earthquakes occurring along with a large number of weaker events. Strombolian activity was noted on the nights of 11 and 13 December. Gas-and-steam plumes, possibly containing small amounts of ash, rose to low levels above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 December-9 December 2003 Cite this Report

Seismicity remained above background levels at Kliuchevskoi with ~130 M 2-2.5 and many smaller earthquakes recorded during 28 November to 5 December. Strombolian activity was observed on the nights of 27 and 29 November and on 29 November a gas-and-steam plume with some ash was emitted. On 2 December a gas-and-steam plume rose to 1 km above the crater and extended to over 20 km E. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 November-2 December 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 21 to 28 November, with 80 shallow M 2-2.5 earthquakes and a large number of weak shallow events recorded. Strombolian activity was seen on the night of 21 November. Gas-and-steam plumes containing some ash rose to low levels above the crater on 23-24 November. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 November-25 November 2003 Cite this Report

Strombolian activity was observed at Kliuchevskoi on 14-15 November. During 14-15 and 18 November, gas-and-ash plumes rose to ~2.5 km above the crater and extended more than 10 km W, E, and NE. During 15-20 November, seismic activity continued to be above background levels with 75 shallow M 1.9-2.5 earthquakes and many small, shallow earthquakes recorded. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 November-18 November 2003 Cite this Report

During 7-14 November, seismicity was above background levels at Kliuchevskoi, with the occurrence of 43 large shallow earthquakes (M 1.9-2.5), a large number of weak shallow earthquakes, and spasmodic tremor. Gas-and-steam plumes rose to ~2.5 km above the crater. Strombolian activity was visible at the volcano's central crater during the evening of 9-10 November. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 November-11 November 2003 Cite this Report

A 7 November report noted continued unrest, with recent (late October) activity including unusual numbers and kinds of earthquakes. During the week ending 7 November tremor took place and earthquakes remained elevated. A 9 November satellite observation revealed an ash and steam plume to ~7 km a.s.l. and extending ~100 km from the summit.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 October-4 November 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 24-31 October, with one to five earthquakes (M 1.6-2.3) occurring per day at depths around 30 km. Several large shallow earthquakes (M 1.7-2.6), and weaker earthquakes occurred. Gas plumes rose to ~700 m above the volcano. Incandescence was seen in the crater during 23-24 October. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

22 October-28 October 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 17-24 October, with one to five M 1.7-2.1 earthquakes occurring per day at depths around 30 km. Four larger (M 2.1-2.5) earthquakes occurred, as well as a large number of weak shallow ones. Gas-and steam plumes were emitted during the week. On 18 October pilots saw an ash plume at a height of ~6.8 km a.s.l., extending more than 10 km NNE. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 October-21 October 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 11-17 October, with one to six magnitude 1.6-2.1 earthquakes per day at depths of ~30 km. Nine shallow M 1.7-2.2 earthquakes were recorded along with many smaller ones. On 9, 10, and 11 October, gas-and-steam plumes with little ash rose to 0.5-1.5 km above the volcano's crater and extended more than 10 km E. Similar plumes on 12 and 16 October extended more than 46 km and 50 km to the E and NE, respectively. Strombolian activity was observed on the night of 10-11 October. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 October-14 October 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 3-10 October, with up to 30 M 1.7-2.2 earthquakes occurring at depths around 30 km. Gas-and-steam plumes, with little ash, rose 1-3 km above the volcano's crater and extended more than 10 km, mainly E. Strombolian activity at the volcano's center crater was visible during several evenings. Kliuchevskoi remained at Concern Color Code Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

1 October-7 October 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 26 September to 3 October. Each day, 2-6 earthquakes (M 1.7-2) occurred at depths around 30 km. During the report period, ash-and-gas plumes rose to ~1 km above the volcano and extended as far as 100 km. During the evenings of 25 and 30 September, and 2 October, Strombolian activity was visible in the volcano's central crater. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 September-30 September 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 19-26 September, with 1-3 earthquakes (M 1.7-2.2) at depths around 30 km. A gas-and-steam plume rose to ~700 m above the crater on 24 September. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

17 September-23 September 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 12-19 September, with 2-6 earthquakes between M 1.7 and 2.2 occurring. Ash-and-gas plumes rose to 100 m above the crater and drifted W. The volcano's western flank was covered by fresh ash. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

10 September-16 September 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 5-12 September, when 2-9 earthquakes with magnitudes less than 2.1 occurred per day at depths of ~30 km. During the week, ash-and-gas, and gas-and-steam plumes were seen. The highest rising ash-and-gas plume reached ~1.5 km above the volcano on 10 September. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

3 September-9 September 2003 Cite this Report

During 29 August to 5 September, seismicity was above background levels at Kliuchevskoi, with 4-7 earthquakes less than M 2.2 occurring per day. at depths around 30 km On 29 August gas-and-steam plumes with minor amounts of ash rose to 1 km above the crater. On the evening of 4 September incandescence was visible in the center of the crater. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 August-2 September 2003 Cite this Report

During 22-29 August, seismicity was above background levels at Kliuchevskoi, with 3-8 earthquakes per day of magnitude less than 2.2 occurring at depths around 30 km. On 26 August at 2300 Strombolian activity was seen in the volcano's center crater. Volcanic bombs were hurled to ~200 m above the crater. There were 5-minute intervals between explosions. During 27-28 August, gas-and-steam plumes with minor amounts of ash rose 1.5-2 km above the volcano's crater and drifted SW. Kliuchevskoi remained at Concern Color Code Orange.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Associated Press

20 August-26 August 2003 Cite this Report

During 15-22 August, seismicity was above background levels at Kliuchevskoi. Up to 15 earthquakes were recorded per day at depths around 30 km. Spasmodic tremor was also recorded. Gas-and-steam plumes rose to 700 m above the volcano, weak fumarolic activity was recorded, and a thermal anomaly was visible on satellite imagery. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 August-19 August 2003 Cite this Report

Seismicity was above background levels during 7-15 August at Kliuchevskoi, with 37-60 earthquakes recorded during 7-9 August with magnitudes up to 2.3. Gas-and-steam plumes rose to 800 m above the volcano and extended ~15 km S. A thermal anomaly was visible on satellite imagery. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

6 August-12 August 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 1-8 August. During 1-6 August, up to 18 earthquakes occurred per day with magnitudes less than 2.1 at depths around 3 km. Gas-and-steam plumes rose to 2 km above the crater. Thermal anomalies were seen on satellite imagery on several days. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

30 July-5 August 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 24 July to 1 August. During 24-28 July, 14-17 earthquakes with magnitudes less than 2.1 occurred each day. The number of earthquakes decreased to 9 on 29 July, and 7 on 30 July. Gas-and-steam plumes rose to a maximum height of ~700 m above the crater. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 July-29 July 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi, with 6-17 M 1.8-2.4 earthquakes occurring each day at depths of ~30 km and at shallower levels. Gas-and-steam plumes rose to a maximum height of ~1 km above the crater. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 July-22 July 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 11-18 July. Several earthquakes occurred each day with magnitudes of 1.3-2.2 at depths around 30 km and at shallower levels. Explosions sent ash clouds to a height of ~1 km above the volcano and during 12-16 July ash clouds reached ~2 km above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 July-15 July 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 4-12 July. Several earthquakes with magnitudes of 1.5-2.2 occurred at depths around 30 km and at shallower levels. The amount of spasmodic tremor decreased by the end of the report week. Ash explosions reached ~1 km above the volcano each day of the report week, except 6 July. On 4 July ash from an explosion reached ~2 km above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 July-8 July 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 27 June-4 July, with earthquakes occurring at depths around 30 km and at shallower levels. The character of seismicity indicated that weak gas-and-ash explosions possibly occurred. Spasmodic tremor was recorded the entire week. On 2 July ash plumes rose to 1 km above the volcano and drifted ESE. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

25 June-1 July 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 20-27 June, with earthquakes occurring at depths around 30 km and at shallower levels. The character of seismicity indicated that weak gas-and-ash explosions possibly occurred. Spasmodic tremor was recorded the entire week. Gas-and-steam plumes rose 50-700 m above the volcano. On 23 June a thermal anomaly and possible ash deposits on the volcano's SE flank were seen on satellite imagery. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

18 June-24 June 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 13-20 June, with the level of spasmodic tremor remaining near the level of the previous week. Earthquakes continued to be registered at depths around 30 km and at shallower levels. The character of seismicity indicated that weak gas-and-ash explosions possibly occurred. On 14,16, and 17 June explosions produced ash-poor plumes 50-500 m above the volcano. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 June-17 June 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 6-13 June. After some diminishing, the level of continuous spasmodic volcanic tremor returned to the same level as the previous week. Earthquakes continued to be registered at depths around 30 km and at shallower levels. The character of seismicity indicated that weak gas-and-ash explosions possibly occurred. A thermal anomaly and an ash-poor plume were visible on satellite imagery. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 June-10 June 2003 Cite this Report

During 30 May to 6 June, seismicity remained above background levels at Kliuchevskoi. The amount of spasmodic volcanic tremor continued to grow slowly and consistently. Earthquakes continued to be registered at depths around 30 km and at shallower levels. The character of seismicity indicated that weak gas-and-ash explosions possibly occurred. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 May-3 June 2003 Cite this Report

Volcanic unrest continued at Kliuchevskoi during 23-30 May. Seismicity was above background levels and the amount of continuous spasmodic volcanic tremor slightly increased. Shallow earthquakes and others at depths around 30 km continued to occur. Gas-and-steam plumes were occasionally visible, but the volcano was obscured by clouds most of the report week. On 30 May at 0030 observers in the town of Klyuchi saw pulsing glow above the volcano's crater. Light bursts occurred every 1-10 minutes, but volcanic bomb traces were absent. Kliuchevskoi remained at Concern Color Code Orange.

Sources: Pravda News; Kamchatkan Volcanic Eruption Response Team (KVERT)

21 May-27 May 2003 Cite this Report

Volcanic unrest continued at Kliuchevskoi during 16-23 May. Seismicity was above background levels, with five M 2-2.1 earthquakes occurring at depths around 30 km during 15-21 May. Continuous spasmodic volcanic tremor occurred during the report period. Gas-and-steam plumes rose above the crater to low levels. On 18 May during 0000-0500, incandescence was visible above the volcano's crater from the town of Klyuchi. This is the first such observation since 1994. Thermal anomalies were visible on satellite imagery during 15-22 May. On 17 May ash deposits were visible on the volcano's E and SE flanks. Kliuchevskoi remained at Concern Color Code Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 May-20 May 2003 Cite this Report

Several explosions occurred at Kliuchevskoi during 9-16 May, and seismicity was above background levels. On 14 May KVERT raised the Concern Color Code to Orange from Yellow. An eruption on 14 May at 1120 produced the week's highest rising ash cloud (~8.5 km a.s.l.). During the report period, instruments recorded 26 to 59 earthquakes per day. They were greater than M 1.25 and at depths of ~30 km. A large number of weak shallow earthquakes and tremor also occurred.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Pravda News

30 April-6 May 2003 Cite this Report

KVERT reported above-background seismicity at Kliuchevskoi during the week ending 1 May. Specifically, there were 25 earthquakes over M 1.25 at ~30 km depth, and 19 earthquakes over M 1.25 at shallower depths, including some within the edifice. In addition, during the same week instruments registered numerous weak, shallow earthquakes, and continuous spasmodic tremor. Residents in the city of Klyuchi saw various gas-and-steam plumes rising to these heights above the crater: on 25 April up to 300 m; and several other late April plumes up to ~ 2 km. The plume of 28 April extended over 5 km to the SE. Videos suggested that plumes escaping the crater in the early morning hours of 2 May could have contained ash.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

23 April-29 April 2003 Cite this Report

A KVERT report on Kliuchevskoi issued on 25 April stated that above-background seismicity, including abundant tremor, prevailed during the week. This report also revealed that the ash explosions of 17-18 April had sent material 1-2 km above the crater. Modest thermal anomalies registered in satellite data for 18-19 April and plumes around that time extended E for 20-200 km. The respective ash-bearing plumes of 20 and 23 April traveled over 10 km NE and 20 km SW. As of 25 April the Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

16 April-22 April 2003 Cite this Report

A moderate vulcanian eruption of Kliuchevskoi began 15 April; it continued through at least 16 April. The eruption was preceded by above-background seismicity, and on 15 April there were ~70 earthquakes per day at ~30-km depth. Instruments registered continuous spasmodic volcanic tremor (up to 4.0 µm/second) and numerous weak shallow earthquakes. According to observers in Klyuchi, on 15 April a series of ash plumes rose up to 300 m above the crater and extended for 10 km. According to satellite data, on 16 April a thin, 175-km-long plume headed E. Observations on 17 April disclosed a zone of ash deposits extending ESE for 20 km from the crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

9 April-15 April 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 4-11 April, with 10-15 earthquakes occurring per day at depths of ~30 km. Continuous spasmodic volcanic tremor and a large number of weak shallow earthquakes were recorded. Gas-and-steam plumes rose to low levels above the crater and fumarolic activity was observed on 7 April. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

2 April-8 April 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 28 March to 4 April, with 24-63 earthquakes occurring per day at depths of ~30 km. Continuous spasmodic volcanic tremor was recorded and a large number of weak shallow earthquakes were registered. Gas-and-steam plumes rose to low levels above the crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 March-1 April 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 21-28 March. During 20-24 March, 6-9 earthquakes occurred at depths of ~30 km. Later seismicity increased, with 26 and 41 earthqakes recorded on 25 and 26 March, respectively. The amount of continuous spasmodic volcanic tremor increased in comparison to the previous week. Gas-and-steam plumes rose to low levels above Kliuchevskoi's crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 March-25 March 2003 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 14-21 March, with 7-9 earthquakes occurring at depths of ~30 km. Continuous spasmodic volcanic tremor was recorded. Gas-and-steam plumes rose 700-1,500 m above Kliuchevskoi's crater on 18-19 March. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

26 February-4 March 2003 Cite this Report

Seismicity at Kliuchevskoi was slightly above background levels during 21-28 February, with 10-14 earthquakes occurring per day at depths of ~30 km. Continuous, spasmodic volcanic tremor was recorded all week. Gas-and-steam plumes rose to low levels and possible ash deposits on the volcano's SE summit were visible on satellite imagery. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 February-25 February 2003 Cite this Report

Seismicity was above background levels during 13-15 February at Kliuchevskoi, and slightly above background levels during 16-19 February. From 14 to 81 earthquakes occurred each day at depths of ~30 km. Continuous spasmodic volcanic tremor was registered during the report week, and gas-and-steam plumes rose to 1 km above the crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 February-18 February 2003 Cite this Report

Seismicity was slightly above background levels during 7-14 February at Kliuchevskoi, with 17-30 earthquakes occurring each day at depths of ~30 km. Continuous spasmodic volcanic tremor was registered during the report week, and gas-and-steam plumes rose to 1.5 km above the crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 February-11 February 2003 Cite this Report

Seismicity was slightly above background levels during 31 January to 7 February at Kliuchevskoi, with 16-39 earthquakes occurring each day, at depths of ~30 km. Continuous spasmodic volcanic tremor was registered during the report week, and gas-and-steam plumes rose to 1.3 km above the crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

15 January-21 January 2003 Cite this Report

Seismicity was slightly above background levels during 10-17 January at Kliuchevskoi, with 12-28 earthquakes occurring each day during 10-12 January and 33-35 earthquakes during 13-15 January. Intermittent spasmodic volcanic tremor was registered during the report week, and gas-and-steam plumes rose to 300 m above the crater. The Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

8 January-14 January 2003 Cite this Report

Seismicity was slightly above background levels at Kliuchevskoi during 6-9 January, with 10-23 earthquakes recorded per day. Steam-and-gas plumes were seen rising to 1 km above the crater. Thermal anomalies were visible on satellite imagery. A probable mudflow, seen on the volcano's SE slope on 7 January, may have emerged after a short explosion to the SE or E, or after powerfulfumarolic activity in the crater. The Concern Color Code was reduced from Orange to Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

31 December-6 January 2003 Cite this Report

Seismicity was slightly above background levels at Kliuchevskoi during 26 December to 3 January, with 3-11 earthquakes occurring per day. On 5 January a faint thermal anomaly, and probable mud flow down the volcano's SSE slope were visible on satellite imagery. According to KVERT, the thermal anomaly and mud flow indicate that a lava flow may have begun to travel down the SSE slope. During 4-6 January, seismicity was slightly above background levels. The Concern Color Code was raised on 6 January from Yellow to Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

24 December-30 December 2002 Cite this Report

A gas-and-ash explosion at Kluichevskoi on 24 December led KVERT to increase the Concern Color Code from Yellow to Orange. Seismicity was above background levels during 19-25 December, with 6-9 earthquakes recorded each day at ~30-km depth. Intermittent spasmodic volcanic tremor was also recorded. On 19, 21, and 23 December gas-and-steam plumes rose 1-2 km above the crater. Visual observations and video data from the town of Klyuchi revealed that a plume from a gas-and-ash explosion on 24 December at 1210 rose 4 km above the crater and drifted WSW. By the 27th the Concern Color Code had been reduced back to Yellow.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

18 December-24 December 2002 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 13-20 December. Seismographs recorded 6-12 earthquakes per day during the report period at depths of ~ 30 km. In addition, intermittent spasmodic volcanic tremor was recorded. Gas-and-steam plumes rose ~1.5 km above the crater and extended E and SE. Kliuchevskoi remained at Concern Color Code Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

11 December-17 December 2002 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 6-13 December. Seismographs recorded 12-24 earthquakes per day during the report period at depths of ~ 30 km. In addition, intermittent spasmodic volcanic tremor was recorded. Gas-and-steam plumes rose 1.5 km above the crater and extended N and NE. Kliuchevskoi remained at Concern Color Code Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

4 December-10 December 2002 Cite this Report

Seismicity was above background levels at Kliuchevskoi during 29 November to 6 December. Up to 33 earthquakes occurred per day during 28 November to 4 December at a depth of ~ 30 km. In addition, intermittent spasmodic volcanic tremor occurred during the report week. On 3 December a gas-and-steam plume rose ~1.3 km above the crater and drifted N and NE. Kliuchevskoi remained at Concern Color Code Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 November-3 December 2002 Cite this Report

Seismicity at Kliuchevskoi was above background levels during 21-24 November, and at background levels during 25-27 November. Each day during the report week 7 to 11 earthquakes occurred at a depth of ~30 km. Gas-and-steam plumes were observed rising to ~2 km above the crater and drifting N and NW. On 24 November weak ashfall was observed around Bylinkina's crater on the volcano's NE slope. Kliuchevskoi remained at Concern Color Code Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

20 November-26 November 2002 Cite this Report

Seismicity remained above background levels at Kliuchevskoi during 15-22 November. The number of deep earthquakes decreased from 26 to 9 during 14-17 November, and remained at nine during the 17th to 20th. Gas-and-steam plumes were seen rising to 1-2 km above the crater and drifting to the W. Kliuchevskoi remained at Concern Color Code Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

13 November-19 November 2002 Cite this Report

KVERT raised the Concern Color Code at Kliuchevskoi from Green to Yellow during 8-15 November. According to data from KMSD GS RAS, seismicity was above background levels at Kliuchevskoi during the report week. During 8-10 November, five to nine earthquakes occurred per day, and during 11-13 November 33-56 earthquakes occurred per day. Intermittent spasmodic volcanic tremor slowly decreased during 8-12 November. A gas-and-steam plume was seen rising 100-900 m above the crater and extended more than 10 km to the E and SE.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

19 June-25 June 2002 Cite this Report

Shallow seismic activity declined during 14-21 June at Kliuchevskoi, but 10-15 earthquakes ~30 km beneath the volcano occurred daily, and weak spasmodic tremor continued to be registered during the week. By the end of the week, shallow seismic events occurred again. Low-level gas-and-steam clouds rose above the volcano on several days. No thermal anomalies or plumes were visible on satellite imagery. KVERT decreased the Concern Color Code at Kliuchevskoi from Yellow ("volcano is restless") to Green ("volcano is in quiet, "dormant" state").

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

12 June-18 June 2002 Cite this Report

Seismicity was above background levels at Kliuchevskoi during most of 7-14 June. On 11 June a ~30-minute-long series of earthquakes (ML less than or equal to 2.8) occurred in the volcano's edifice. Continuous spasmodic tremor continued to be recorded during the week and 22-48 earthquakes occurred per day ~30 km below the volcano. Based on visual and seismic data there was no evidence of recent explosive activity at the volcano. No thermal anomalies or ash plumes were observed on satellite imagery. Kliuchevskoi remained at Concern Color Code Yellow ("volcano is restless").

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

5 June-11 June 2002 Cite this Report

During most of the week of 31 May-7 June seismicity was above background levels at Kliuchevskoi, and continuous spasmodic tremor was registered. On 31 May a series of earthquakes less than or equal to ML (local magnitude) 2.3 were registered in the volcano's edifice, and about 20 ~30-km-deep earthquakes occurred per day under the volcano. On 5 June at 1820 volcanic tremor began to gradually diminish and by the end of the week shallow seismic activity had decreased. Low-level gas-and-steam plumes rose above the crater and no thermal anomalies or plumes were observed on satellite imagery. Kliuchevskoi remained at Concern Color Code Yellow ("volcano is restless").

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

29 May-4 June 2002 Cite this Report

An increase in volcanic tremor at Kliuchevskoi led KVERT to raise the Concern Color Code from Green ("volcano is in quiet, "dormant" state") to Yellow ("volcano is restless") on 31 May. During most of the report week (24-31 May) seismicity was near background levels. Weak shallow earthquakes, other earthquakes ~30 km under the volcano, and episodes of weak spasmodic tremor were registered. On 24 and 27 May gas-and-steam plumes rose 100 m above the crater. Spasmodic volcanic tremor began to increase on 30 May at 0810, declined at 1000, and began to increase again around 2200. Tremor was still recorded on 31 May. No thermal anomalies or plumes were observed on satellite imagery.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

27 February-5 March 2002 Cite this Report

The Tokyo VAAC received reports that Kliuchevskoi began erupting on 27 February at 1455. Reportedly, an ash cloud was produced to a height of ~6.4 km a.s.l. and drifted to the NE. No ash was visible on satellite imagery. According to reports KVERT received from the Research Laboratory of Seismic and Volcanic Activity in Kamchatka, there was neither a seismic signal detected at Kliuchevskoi on 27 February at 1455 nor an ash plume visible on video footage.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

21 November-27 November 2001 Cite this Report

A gradual decrease in seismicity under Kliuchevskoi during 16-23 November led KVERT to reduce the Concern Color Code from Yellow to Green. The tallest gas-and-steam plume of the reporting interval was produced on 19 November. The plume rose 700 m above the dome and extended SE for more than 10 km.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 November-20 November 2001 Cite this Report

An increase in seismicity at Kliuchevskoi during 13 November to at least 16 November led KVERT to raise the Concern Color Code from Green to Yellow. On 13 November at 1619 seismicity sharply increased from background levels when a swarm of shallow earthquakes began; these had magnitudes less than or equal to 3. During 13-15 November more than 150 earthquakes occurred with magnitudes less than or equal to 1.7. Prior to the seismicity increase, on 9 November a steam plume rose 600 m above the crater and during 11-13 November gas-and-steam plumes rose 50-100 m above the crater.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

28 March-3 April 2001 Cite this Report

The KVERT reported that during the beginning of the report period (23-30 March), seismic activity was above background levels with spasmodic tremor and shallow earthquakes registered, but gradually decreased towards the end of the week. The KVERT lowered the Level of Concern Color Code from Yellow to Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

21 March-27 March 2001 Cite this Report

The KVERT reported that during 16-22 March seismic activity was above background levels, with interrupted spasmodic tremor and shallow earthquakes registered. On 18-19 March a gas and steam plume rose 50-100 m above the volcano. On 22 March the volcano was quiet. On other days, the volcano was obscured by clouds. The level of Concern Color Code remained at Yellow.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

14 March-20 March 2001 Cite this Report

The KVERT reported that during 9-15 March seismic activity was above background levels, with interrupted spasmodic tremor and shallow earthquakes registered. Between 1925 and 1940 on 15 March, an intense series of shallow earthquakes were registered. Gas-and-steam plumes rose 2 km above the volcano on 12 and 14 March, and others reached 100-250 m above the volcano on 9, 11, and 13 March. The Concern Color Code remained at Green.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

7 March-13 March 2001 Cite this Report

The KVERT reported that during 2-8 March seismicity was at background levels, with weak spasmodic tremor occasionally registered. On 4 March a gas-and-steam plume rose 600-1,000 m above the volcano and extended more than 10 km to the NE. As reported by the Tokyo VAAC, GMS-5 imagery showed that the plume rose to a height of ~9.5 km a.s.l. The Concern Color Code remained at Green.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT); Tokyo Volcanic Ash Advisory Center (VAAC)

28 February-6 March 2001 Cite this Report

Based on satellite imagery and pilot reports, the Tokyo VAAC reported that an eruption may have occurred at Kliuchevskoi. The ash cloud produced from the eruption rose to a height of ~9.5 km and was visible on GMS-5 imagery at 1532 on 4 March. By 1832 the same day the ash cloud was no longer visible on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)

Bulletin Reports - Index

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

10/1974 (CSLP 135-74) Lava flow moves into glacier; weak explosions

07/1978 (SEAN 03:07) Lava flow accompanied by crater wall collapse and moderate seismicity

01/1980 (SEAN 05:01) Tephra and lava flow

03/1980 (SEAN 05:03) Large ash explosions from summit; lava from flank fissure

12/1981 (SEAN 06:12) Hot spot and plume on satellite images

12/1982 (Ref 1988) Intermittent eruptive activity from March through December 1982

03/1983 (SEAN 08:03) Earthquake swarm then lava flow from NE flank vent

05/1983 (SEAN 08:05) Numerous flank lava flows; weak summit explosions

05/1984 (SEAN 09:05) Strombolian activity builds cinder cone; lava flow

08/1984 (SEAN 09:08) Tephra ejection; lava flows; lahars

01/1985 (SEAN 10:01) Tephra ejection; lava flow with fountains

11/1985 (SEAN 10:11) Ash explosions; lava flows

12/1985 (SEAN 10:12) Large ash column; lava melts ice, producing mudflow

12/1985 (SEAN 11:12) Lava flow and incandescent tephra

01/1987 (SEAN 12:01) Lava flows; directed explosions; plumes on satellite images

02/1987 (SEAN 12:02) Strong explosions; lava from flank fissure

03/1988 (SEAN 13:03) Summit/flank eruption; seismic swarm; plume

04/1988 (SEAN 13:04) Strong summit explosions; lava from flank fissures

01/1990 (BGVN 15:01) Strong summit explosions cause ashfalls 375 km away; SE flank lava fountains feed lava flow

03/1990 (BGVN 15:03) Strong summit tephra eruption; basaltic lava from SE flank vent

03/1991 (BGVN 16:03) Small summit eruption

04/1991 (BGVN 16:04) Small summit plume; ash on SE flank

06/1991 (BGVN 16:06) Small plume seen from satellite image

01/1992 (BGVN 17:01) Explosions feed small ash plumes

05/1992 (BGVN 17:05) Small explosions eject ash

04/1993 (BGVN 18:04) Small gas and ash explosions

05/1993 (BGVN 18:05) Seismicity continues; small explosions

06/1993 (BGVN 18:06) Lava fountaining and explosive ash eruptions

07/1993 (BGVN 18:07) Gas-and-ash plumes; lava flows down W slope; high seismicity

08/1993 (BGVN 18:08) Gas-and-ash plume persists; lava flow stops

10/1993 (BGVN 18:10) Gas-and-ash plumes, minor seismicity, and weak fumarolic activity continues

11/1993 (BGVN 18:11) Low seismicity; 15-km-long plume in early December

12/1993 (BGVN 18:12) Spasmodic tremor and temporally coincident shallow earthquakes

01/1994 (BGVN 19:01) Weak volcanic tremor at variable levels; fumarolic activity

03/1994 (BGVN 19:03) Weak seismicity and fumarolic activity continue

04/1994 (BGVN 19:04) Weak fumarolic activity, seismicity, and tremor

06/1994 (BGVN 19:06) Phreatic explosions; variable seismicity continues

08/1994 (BGVN 19:08) Eruption sends gas-and-ash bursts at least 3 km high; lava fountaining

09/1994 (BGVN 19:09) Eruption sends plume to 15-20 km altitude and produces lava flows

10/1994 (BGVN 19:10) Eruption sends plume to 15-20 km altitude and produces lava flows

11/1994 (BGVN 19:11) Moderate explosive eruption causes minor ashfall 30 km away

12/1994 (BGVN 19:12) Small eruption in mid-January

06/1996 (BGVN 21:06) Normal seismic activity, but degassing persists

08/1996 (BGVN 21:08) Background seismicity and noteworthy tremor

10/1996 (BGVN 21:10) Seismicity above background; fumarolic plumes up to 1 km tall

12/1996 (BGVN 21:12) Above-background seismicity; ash-and-steam plumes up to 3 km tall

02/1997 (BGVN 22:02) Seismicity remains elevated; gas-and-ash plume to 4 km over crater

03/1997 (BGVN 22:03) Continuous presence of gas-and-steam plume up to 4 km above crater

09/1997 (BGVN 22:09) Frequent gas-and-steam plumes; infrequent ash plumes; low seismicity

11/1997 (BGVN 22:11) Elevated seismicity during 13 October-1 December; gas-and-steam plumes

01/1998 (BGVN 23:01) Earthquakes, tremor, and modest gas-and-steam plumes through early January

02/1998 (BGVN 23:02) Earthquakes, tremor, and gas-and-steam plumes throughout February

03/1998 (BGVN 23:03) Earthquakes and frequent fumarolic plumes

04/1998 (BGVN 23:04) Seismicity above background, various fumarolic plumes

06/1998 (BGVN 23:06) Fumarolic plumes; 43-minute-long series of earthquakes on 12 July

08/1998 (BGVN 23:08) Gas-and-ash explosions during 23-25 July

09/1998 (BGVN 23:09) Explosions, ash 2-3 September raise concern to yellow alert

10/1998 (BGVN 23:10) Background seismic and fumarolic activity during October

12/1998 (BGVN 23:12) Series of shallow earthquakes 23 December

01/1999 (BGVN 24:01) Series of deep and shallow earthquakes

03/1999 (BGVN 24:03) Elevated seismicity and large steam plumes continue through March

05/1999 (BGVN 24:05) Series of ash explosions and shallow earthquakes during May

07/1999 (BGVN 24:07) May-August seismicity weak; traces of ash in emissions

11/1999 (BGVN 24:11) Variable fumarolic plumes and episodes of increased seismicity

04/2000 (BGVN 25:04) Frequent fumarolic plumes, one to 10 km altitude on 30 January

09/2000 (BGVN 25:09) Seismic swarms, fumarolic activity, and gas-and-ash explosions

04/2001 (BGVN 26:04) Consistent gas-and-steam emissions; high seismicity

06/2002 (BGVN 27:06) Increased seismicity prompts KVERT to raise hazard status to Yellow

11/2002 (BGVN 27:11) Above-background seismicity June-November 2002

02/2003 (BGVN 28:02) Seismicity above background levels; explosion and thermal anomaly

07/2003 (BGVN 28:07) Gas-and-steam plumes June-August with occassional ash plumes

11/2003 (BGVN 28:11) Ash explosions and Strombolian activity through early December

12/2003 (BGVN 28:12) 2003 ends with ~3-km-tall steam plumes, M 2 earthquakes, tremor

04/2004 (BGVN 29:04) Background seismicity March-April 2004; ash plumes on 8 April

03/2005 (BGVN 30:03) Strombolian eruptions and lava flows during January-March 2005

06/2007 (BGVN 32:06) Significant eruptive activity resumes in mid-February 2007

03/2009 (BGVN 34:03) Eruption in 2007 changed summit crater; ongoing 2008-2009 lava flows

06/2010 (BGVN 35:06) Ongoing 2009-2010 eruptions; 243-km-long plume during February 2010

07/2013 (BGVN 38:07) Eruptions continue, 19 February 2010-15 November 2013

10/2014 (BGVN 39:10) Two eruptive pulses: 15 August-20 December 2013 and 1 January-24 March 2015

04/2017 (BGVN 42:04) Mixed explosive and effusive eruption ongoing from August 2015 through March 2017

11/2017 (BGVN 42:11) Eruption appears to have subsided after March 2017; ash plumes persist into October

05/2018 (BGVN 43:05) Intermittent moderate gas, steam, and ash plumes during December 2017-February 2018

08/2018 (BGVN 43:08) Intermittent moderate gas, steam, and ash emissions; no ash seen after 15 June 2018

07/2019 (BGVN 44:07) Weak thermal anomalies and moderate Strombolian-type eruptions in September 2018-June 2019

10/2019 (BGVN 44:10) Ongoing weak thermal anomalies during July-September 2019, but no ash plumes after 1 August

06/2020 (BGVN 45:06) Strombolian activity November 2019 through May 2020; lava flow down the SE flank in April

09/2020 (BGVN 45:09) Strombolian activity, gas-and-steam and ash plumes, and a lava flow during June-early July 2020

01/2021 (BGVN 46:01) Renewed activity in October 2020 with explosions, lava flows, and ash plumes

04/2021 (BGVN 46:04) Ash emissions and lava flows during January-February, new NW-flank vent and flow February-March 2021

12/2022 (BGVN 47:12) Strombolian eruption in November 2022

Information is preliminary and subject to change. All times are local (unless otherwise noted)

October 1974 (CSLP 135-74)

Lava flow moves into glacier; weak explosions

A lava flow from a new radial fissure on the SSW slope of Kliuchevskoi has reached a length of 2.5 km. The flow has moved into the glacier. Weak explosive activity is continuing.

Information Contacts: Y.M. Doubik, Institute of Volcanology, Petropavlovsk.

July 1978 (SEAN 03:07) Cite this Report

Lava flow accompanied by crater wall collapse and moderate seismicity

Activity in the summit crater increased in March, preceded by an earthquake swarm. After a 3 month recess, new lava appeared in the crater and poured through a breach in the NW rim onto the flanks. An 80-m cone was built in the center of the crater and "intense" collapse occurred on the crater walls and the NW Sciarra. Moderate seismicity accompanied the activity.

Information Contacts: B. Ivanov, IVP.

January 1980 (SEAN 05:01) Cite this Report

Tephra and lava flow

Tass reported, in an article dated 24 January, that Kliuchevskoi had begun to erupt. Gas, ash, and "hot rocks" were ejected, and a lava flow was extruded. Heavy snowfall impeded observation of the crater, but the staff of the local IVP station were monitoring the volcano with instruments.

Information Contacts: Tass.

March 1980 (SEAN 05:03) Cite this Report

Large ash explosions from summit; lava from flank fissure

Soviet press sources described a renewed eruption at Kliuchevskoi. After a series of volcanic earthquakes, ash was ejected from the summit in bursts that rose as much as 5 km. Ashfall covered an area of more than 6,000 km². On 6 March, a fissure more than 1 km long opened on the NE flank and began to emit gases. The next day, lava extrusion from the fissure started at 1.5 km altitude (the summit is at 4,850 m above sea level). Four small cones, up to 20 m high, formed along the fissure. As of 14 March, lava had flowed 1 km downslope and ash emission from the summit crater was continuing. IVP personnel were investigating the activity at the eruption site.

Further Reference. Stepanov, V.V., and Chirkov, A.M., 1981, Activity of the upper crater of Kliuchevskoi volcano in January-March 1980: Volcanology and Seismology, no. 1, p. 103-106.

Information Contacts: Tass; V. Khudyakov; 14 March 1980 edition of "Sovetskaya Rossiya", Moscow.

December 1981 (SEAN 06:12) Cite this Report

Hot spot and plume on satellite images

A small hot area, apparently centered on the summit, was first noted on the thermal infrared band of a NOAA 6 satellite image on 21 December at 1057, and a hot spot was present 22 hours later. An average temperature of 320°C within a given image element (or "pixel", corresponding to a 1.1 x 1.1 km ground area) will saturate the sensors for this band, so it is not possible to determine the actual temperature of the heat source nor its true dimensions. On the next image, at 1233 on 22 December, the hot spot was accompanied by a diffuse plume that extended about 350 km SE. The hot spot had decreased in size 24 hours later, and the plume was smaller (detectable only to 60 km to the E) and more diffuse. Clouds partially obscured the volcano for the next several daily images, but a small plume seemed to be present. On the next clear-weather image, at 1400 on 28 December, there appeared to be a small warm area at the summit, but no plume was evident. No additional activity has been observed on satellite imagery. There have been no reports from ground observers.

Information Contacts: M. Matson, NOAA/NESS.

December 1982 (Ref 1988)

Intermittent eruptive activity from March through December 1982

Occasional small explosions ejected ash and incandescent bombs 24 March-2 May 1982. A mid-September overflight revealed a collapse depression 300 m in diameter in place of the 1977-80 cinder cones. Ash emission resumed 7-8 October. Activity became progressively more intense through November, and bomb ejection resumed in December.

Reference. Ivanov, B.V., Chirkov, A.M., Dubik, Yu. M., Khrenov, A.P., Dvigalo, V.N., Razina, A.A., Stepanov, V.V., and Chubarova, O.S., 1988, Active volcanoes of Kamchatka and Kurile Islands: status in 1982: Volcanology and Seismology, v. 6, p. 623-634 (English translation of paper in Volcanology and Seismology, 1984, no. 4, p. 104-110).

Information Contacts:

March 1983 (SEAN 08:03) Cite this Report

Earthquake swarm then lava flow from NE flank vent

An earthquake swarm on the NE flank began 28 February. The majority of the events had foci above sea level (Kliuchevskoi's summit elevation is 4,850 m) and their maximum magnitude was 3. Based on the swarm's character, the IVP predicted that a flank eruption would start between 4 and 9 March. On 8 March a crater opened at 3,000 m altitude on the NE flank. Activity from the crater was purely effusive, producing an andesitic basalt flow that was 3 km long by 18 March.

Further References. Special issue on the 1983 eruption of Kliuchevskoi: Volcanology and Seismology, 1988, 148 pp. (English translation of Volcanology and Seismology, 1985, no. 1) (8 papers).

Panov, V.K., and Slezin, Y.B., 1985, The mechanism of formation of a lava field during the Predskazanny flank eruption, 1983, Klyuchevskoy volcano, Kamchatka: Volcanology and Seismology, no. 3, p. 3-13.

Tokarev, P.I., 1985, Prediction of lateral eruption of Kliuchevskoy volcano in March 1983: JVGR, v. 25, p. 173-180.

Information Contacts: B. Ivanov, IVP.

May 1983 (SEAN 08:05) Cite this Report

Numerous flank lava flows; weak summit explosions

The NE flank eruption was continuing in early June. As many as 15 lava flows were simultaneously active, some reaching 5 km in length. At the end of May, the maximum discharge rate was 10 m³ per second. Weak explosions occurred from the summit crater. The activity was not visible on NOAA weather satellite imagery returned in May.

Information Contacts: G. Bogoyavlenskaya, IVP; M. Matson, NOAA.

May 1984 (SEAN 09:05) Cite this Report

Strombolian activity builds cinder cone; lava flow

Continuous volcanic tremor and night glow over the crater began in March. Tremor and the number of explosive earthquakes increased from late March through May. During this period, the amplitude of volcanic tremor at 14 km distance and the maximum amplitude of explosive earthquakes reached 2 and 5 µ respectively. Since mid-May, a cinder cone has been visible in the central part of the crater. On 22 May, as moderate Strombolian activity continued, lava began to pour into the NW valley.

Further Reference. Tokarev, P.I., 1985, Eruption of Kliuchevskoi volcano in March-April 1984 and estimation of the observation data: Volcanology and Seismology, no. 1, p. 106-108.

Information Contacts: B. Ivanov, IVP.

August 1984 (SEAN 09:08) Cite this Report

Tephra ejection; lava flows; lahars

Eruptive activity continued through August. During periods of maximum activity ash was ejected to 5 km and bombs to 1 km above the crater rim. Lava flowed to the NW, NE, and SW from the central crater; the largest flow advanced along the NW valley to about 3 km above sea level and crossed a glacier, forming mud flows. A cinder cone has formed inside the central crater.

On 17 August between 0733 and 1027, high-resolution thermal infrared and visual images from polar orbiting weather satellites showed a plume extending about 200 km SE from the volcano below about 6 km altitude. Soviet volcanologists confirmed these observations, reporting that on 16-17 August a 15 km-wide ash plume extended 200 km from the volcano.

Information Contacts: B. Ivanov, IVP.

January 1985 (SEAN 10:01) Cite this Report

Tephra ejection; lava flow with fountains

Kliuchevskoi's summit eruption continued in November and December. Lava flows reached 1.5 km in length. Gas and ash columns rose 2-4 km above the summit and bombs reached 300 m height. At times lava fountains were observed above the crater rim. Eruption character remained constant through mid-January.

Thermal infrared images from the NOAA 6 polar orbiting satellite on 23 November (at 1852) and 24 November (at 0839) showed narrow plumes emerging from Kliuchevskoi and extending roughly 60 km E. Soviet volcanologists reported that the ash column rose to about 4 km above the crater 23-24 November.

Further Reference. Gordeev, E.I., Mel'nikov, Yu.Yu., Sinitsin, V.I., and Chebrov, V.N., 1986, Volcanic tremor of Kliuchevskoi volcano (eruption of summit crater in 1984): Volcanology and Seismology, no. 5, p. 39-53.

Information Contacts: B. Ivanov, IVP; M. Matson and W. Gould, NOAA.

November 1985 (SEAN 10:11) Cite this Report

Ash explosions; lava flows

The quoted part of the following report is from S. Fedotov. "Activity at Kliuchevskoi's summit crater has increased since 17 August, following a period of slight fumarolic activity. Since then, the height of steam and gas explosions increased gradually from 200 to 1,000 m, and reached 3,000 m between 5 and 11 November; the number of ash explosions has increased as well. Since 4 November, lava fountains 300-500 m high from two vents in the crater have been observed. Lava flows more than 2 km long poured from the summit crater onto the SW and NE flanks of the volcano."

Moscow Domestic Service reported that powerful explosions occurred on the slope of the volcano on 2 December, and that eruptions at the summit were continuing.

[This report was not included in GV 75-85.]

Information Contacts: S. Fedotov, IV; Moscow Domestic Service.

December 1985 (SEAN 10:12) Cite this Report

Large ash column; lava melts ice, producing mudflow

B.V. Ivanov reported that the eruption that began in August continued through early January. Lava fountaining from two flank vents was almost continuous. On 1 December, a series of NW-flank phreatic explosions produced an eruption column that rose to 5.2 km above the crater rim (10 km altitude). These explosions were accompanied by Vulcanian ash explosions from the summit crater and by lightning discharges. During subsequent days, ash explosions reached 1.5 km height. Lava flows descended the NW flank to 2.8 km above sea level. In early January, lava fountains were 200 m high, explosions ejected tephra to 100 m height, and short (300 m) lava flows poured onto the SE flank.

Moscow television reported that during the night of 1-2 December, a 50-m-wide lava flow melted a channel in glacial ice, producing a mudflow that traveled 35 km to the Kamchatka River. The 1 December eruption column was reported to have reached its 5.2-km height in 6 minutes. S.A. Fedotov noted (in the television interview) that data collected during a flight the morning of 12 December suggested that 10 metric tons of ash were being ejected per second, and that lava was probably being discharged at more than 50 metric tons per second.

Infrared images from polar-orbiting weather satellites showed plumes from the Kliuchevskoi/Bezymianny area on several days in early December, although weather clouds often obscured the Kamchatka Peninsula. On 2 December at 0237, a NOAA 9 image showed a faint plume emerging from the vicinity of Bezymianny. Two days later at 0216, two weak plumes seemed to be emerging from the area, perhaps one from Kliuchevskoi and one from Bezymianny. On 8 December at 0832, a narrow plume extended about 25-30 km N, probably from Kliuchevskoi.

[This report was not included in GV 75-85.]

Information Contacts: S.A. Fedotov and B.V. Ivanov, IV; Moscow Television Service; Will Gould, NOAA/NESDIS.

December 1985 (SEAN 11:12) Cite this Report

Lava flow and incandescent tephra

Geologists from the IV noted vigorous activity . . . during an aerial survey . . . at the beginning of January. Incandescent bombs were thrown to [500 m] above the crater, accompanied by vigorous gas emission. A large lava flow was advancing down the W flank [see also 13:4].

Information Contacts: Moscow Domestic Service.

January 1987 (SEAN 12:01) Cite this Report

Lava flows; directed explosions; plumes on satellite images

On 26 December, after 5 months of quiet [but see 13:4], two vents from an intracrater scoria cone ejected bombs and ash. Bombs reached 300 m height. Rare gas/steam explosions, mixed with some ash, fed a 1-km eruption column. On 29 December, lava flows poured from a vent near the foot of the scoria cone (last active in July) onto the N and NW flanks. In January, pyroclastic material was ejected obliquely from the crater onto the volcano's flanks. The eruption decreased in intensity on 20 January. Images from the NOAA 9 polar orbiting satellite at 1617 on 21 January showed a 25-km-long plume spreading SW that had grown to 40 km by 0843 the next day.

Weather satellite images showed renewed activity on 17 February with larger plumes late 19 February. Plumes extended as much as 300 km from the volcano (table 1) and were continuing to form as of 20 February. Comparisons of plume temperatures and directions of plume movement with temperature and wind data recorded by radiosondes (launched 15 km to the N) indicated that plumes reached as much as 9 km altitude.

Table 1. Descriptions of Kliuchevskoi plumes from infrared weather satellite images, 17-20 February 1987. Plume altitudes were estimated by comparing wind data from radiosondes launched 15 km N of the volcano with directions of plume movement.

Date	Time	Altitude	Description
17 Feb 1987	1800	~9 km	125 km to the SE
17 Feb 1987	2100	~9 km	250 km to the SSE
18 Feb 1987	0000	--	Small 'cold spot' indicating activity
18 Feb 1987	0900	~3 km	125 km to the SSW
18 Feb 1987	1017	~3 km	65 km to the SSW, curving SE at its distal end
19 Feb 1987	0000	--	100 km to the SW
19 Feb 1987	0150	--	180 km to the SE
19 Feb 1987	1126	--	180 km to the SSE
19 Feb 1987	1800	--	190 km to the ESE
19 Feb 1987	2100	--	250 km long, about 50 km wide
20 Feb 1987	0000	more than 7.5 km	250 km long
20 Feb 1987	0600	~7.5 km	300 km ESE

Information Contacts: A. Khrenov and G. Bogoyavlenskaya, IV; M. Matson, S. Kusselson, and W. Gould, NOAA/NESDIS.

February 1987 (SEAN 12:02) Cite this Report

Strong explosions; lava from flank fissure

Soviet geologists reported that after intense summit crater explosive activity a NE-trending fracture (azimuth 135°) opened 24 February [but see 13:4] on the SE flank at 3,900-3,400 m altitude. Small amounts of lava were quietly emitted along the fracture. The flank eruption ceased on 26 February.

Small plumes had been intermittently visible on satellite images (figure 1) since 18 January. More vigorous activity was evident beginning 17 February and was almost continuous through 24 February (table 2). Maximum plume length was 500 km and maximum altitude may have reached 13.7 km.

Figure 1. NOAA 10 thermal infrared (3.8 µm) satellite image on 18 February at 1017. A plume extends 65 km from Kliuchevskoi at ~3 km altitude. Courtesy of NOAA/NESDIS.

Table 2. Descriptions of Kliuchevskoi plumes from infrared weather satellite images, 21-28 February 1987. Plume altitudes were estimated by comparing wind data from radiosondes launched 15 km N of the volcano with directions of plume movement.

Date	Time	Altitude (km)	Length (km)	Direction	Satellite
21 Feb 1987	1022	1.5-7.2	65	ESE	NOAA 10
21 Feb 1987	1200	1.5-7.2	375	ESE	GMS
21 Feb 1987	1500	1.5-7.2	250	ESE	GMS
21 Feb 1987	1800	9.2-10.4	125	E	GMS
21 Feb 1987	2100	1.5-3.0	150	E	GMS
22 Feb 1987	0000	1.5-3.0	440	E	GMS
22 Feb 1987	0600	3.0	125	E	GMS
22 Feb 1987	0900	5.6-11.8	250	ENE	GMS
22 Feb 1987	1031	9.2-13.7	105	ENE	NOAA 10
22 Feb 1987	1200	9.2-13.7	440	ENE	GMS
22 Feb 1987	1500	9.2-13.7	500	ENE	GMS
22 Feb 1987	1800	5.6-10.4	500	ENE	GMS
22 Feb 1987	2100	5.6-10.4	500	ENE	GMS
23 Feb 1987	0000	10.4-11.8	310	ENE	GMS
23 Feb 1987	0300	--	cloudy	--	GMS
24 Feb 1987	0600	--	cloudy	--	GMS
24 Feb 1987	0900	5.6	190	NW	GMS
24 Feb 1987	1448	5.6	125	NW	NOAA 9
24 Feb 1987	1500	5.6	500	NW	GMS
24 Feb 1987	1800	3.0	500	NW	GMS
24 Feb 1987	2100	3.0	500	NW	GMS
28 Feb 1987	0442	--	20	WSW	NOAA 9

Information Contacts: A. Khrenov, IV; M. Matson and W. Gould, NOAA/NESDIS.

March 1988 (SEAN 13:03) Cite this Report

Summit/flank eruption; seismic swarm; plume

Simultaneous summit and flank eruptions at Kliuchevskoi 6-9 April were accompanied by a swarm of M 2.5 earthquakes. On 10 April at 1021, an image from the NOAA 10 polar orbiting weather satellite showed a plume extending 20-30 km SW from the Kliuchevskoi/Bezymianny area.

Information Contacts: S. Fedotov and N. Zharinov, IV; W. Gould, NOAA/NESDIS.

April 1988 (SEAN 13:04) Cite this Report

Strong summit explosions; lava from flank fissures

"Kliuchevskoi has been very active during the past several years. Most eruptions took place from the summit crater but there were occasional flank eruptions. The 1980 and 1983 flank eruptions were limited to effusive activity.

"A violent Vulcanian-Strombolian eruption started at the end of November 1986 and was continuing in January-February 1987. In January, the eruption column rose 1-2 km and bombs were ejected to 100-300 m height. Two or three vents were active in the central crater, forming a cinder cone. Lava flowed onto the SW and NW flanks.

"The eruption intensified in February (figure 2). Eruption column heights reached 3-4 km at times and bombs were ejected to 600 m above the crater. Lava flowed down the NE flank, reaching 3,200 m elev, 1,650 m below the summit. The most violent activity was observed on 19 February, when the eruption column rose 5.5 km and bombs reached 1 km height. Explosive intensity decreased after 20 February. On 22 February, a radial fissure opened at 3,750 m altitude on the SE flank. Lava from the fissure advanced <1 km. On 6 March a new flow originated from a fissure lower on the SE flank. Some of this lava flowed under Schmidt Glacier at 2,900 m altitude. Flank eruptions ended on 10 March. The summit cinder cone collapsed in June, forming a pit 200 m in diameter.

Figure 2. Oblique airphoto of Kliuchevskoi from the NE on 9 February 1987, showing an eruption column emerging from the summit. Photo by A.B. Belousov.

"Summit activity resumed in July. Activity was primarily Strombolian, ejecting bombs to 200-300 m height from 3-5 new vents. A weak eruption cloud rose 0.5-1 km, with occasional ash ejections to 1.5 km. Between 11 and 13 September, lava began to flow onto the NW flank, advancing about 1 km before activity became less intense in early October and ended on the 12th. The pit formed in June by cinder cone collapse was filled with another cinder cone.

"Activity resumed on 1 December when a series of explosions ejected a 0.4-1 km plume and ash and bombs that rose to 50-150 m height. A small lava flow descended the NW flank 13-24 December. Lava effusion started on the SW flank on 22 December. Activity continued into 1988."

Further Reference. Gorelchik, V.I. and Zharinov, N.A., 1988, Mechanism of Klyuchevskoy flank eruptions of 1974, 1980, 1983 and 1987 as shown by seismological and geodetical data: Proceedings, Kagoshima International Conference on Volcanoes, p. 75-78.

Information Contacts: G. Bogoyavlenskaya and A.B. Belousov, IV.

January 1990 (BGVN 15:01) Cite this Report

Strong summit explosions cause ashfalls 375 km away; SE flank lava fountains feed lava flow

Explosive activity from summit and flank vents emitted ash and lava October-December 1989 and January 1990. Up to 5 ejections/minute from three vents in the summit crater sent ash to 2 km above the summit in December, with a visible plume stretching 20 km from the volcano. Lava fountaining, 30-50 m high from SE flank vents at 4100-4200 m altitude, fed two lava flows that moved SE and E to 2,500 m altitude. Violent explosive activity from the summit crater resumed 29 January, ejecting a 6-km ash plume that extended 60 km from the volcano [see also 15:3]. An incandescent cloud 600-1,500 m high pulsated at the base of the plume, which generated lightning at its top. Ashfall on the Bering Islands (~375 km SE of the volcano) was reported 1 February. Activity also occurred from a SE-flank crater.

Information Contacts: B. Ivanov and E. Zhdanova, IV.

March 1990 (BGVN 15:03) Cite this Report

Strong summit tephra eruption; basaltic lava from SE flank vent

During an overflight by geologists on 2 February, vigorous ash emission fed a large eruption column that rose to ~5 km height and had a basal diameter of ~400-600 m (figure 3). Individual ash bursts were visible at the base of the column, although ash emission appeared to be continuous. A new vent was noted at 4,500 m elev on the NE slope of the Apakhonchich valley, on the upper SE flank. Vapor jets 200-300 m high were distinctly visible above this vent. A subsidiary vent downslope (at 3,970 m elev) fed basaltic lava flows. An ash plume extended 60-80 km E. The ashfall area on 2 February was ~1,600 km².

Figure 3. Tephra cloud from Kliuchevskoi's summit crater on 2 February 1990, in photograph looking roughly E. Arrow 1 indicates the new vent at 4,600 m elev on the SE flank, arrow 2 the effusive vent at 3,970 m elev. Courtesy of B. Ivanov.

Images from the NOAA 10 and 11 polar orbiting satellites showed several plumes from Kliuchevskoi. On 22 February at 1548, a thin plume extended ~80 km SE. A plume was next visible on 10 March at 0956. Although obscured by weather clouds a short distance ENE of the volcano, it formed a distinct cold area on the infrared image, indicating that it was at relatively high altitude. On 12 March at 0335, a very thin plume stretched 15-20 km NE from the Kliuchevskoi area, and on 15 March at 0942, a small diffuse plume extended S from the volcano. A thin plume extended 250 km NE on 3 April at 0903. Weather clouds . . . may have obscured additional eruptive activity.

Information Contacts: B. Ivanov, IV; W. Gould, NOAA/NESDIS.

March 1991 (BGVN 16:03) Cite this Report

Small summit eruption

A small eruption from the summit crater occurred at 1033 on 8 April. No activity has been reported since then.

Information Contacts: E. Gordeev, IV; T. Miller, AVO.

April 1991 (BGVN 16:04) Cite this Report

Small summit plume; ash on SE flank

A Space Shuttle photograph on 29 April at 1248 shows a plume, apparently containing ash, rising about 1 km above the summit and extending about 15 km downwind. Snow on the SE flank appeared to be ash-covered. A small summit eruption occurred on 8 April, but no additional eruptive activity has been reported.

Information Contacts: C. Evans, Lockheed, Houston.

June 1991 (BGVN 16:06) Cite this Report

Small plume seen from satellite image

The NOAA 10 polar-orbiting weather satellite showed a plume ~20 km long, extending S from the summit then turning SW, on 24 June at 1024.

Information Contacts: W. Gould, NOAA/NESDIS.

January 1992 (BGVN 17:01) Cite this Report

Explosions feed small ash plumes

Distinct, single explosions produced ash columns rising 1,000 m on 25-26 January. Although the volcano was not visible from the ground on 27-29 January, a 29 January Space Shuttle photograph showed a steam plume rising from the apparently ash-covered summit region. Earthquake swarms had been recorded in the vicinity of the volcano since the beginning of January.

Information Contacts: A. Ovsiannikov, E. Zhdanova, and S. Zharinov, IVGG; C. Evans, Lockheed, Houston.

May 1992 (BGVN 17:05) Cite this Report

Small explosions eject ash

During a 13 May visit, two explosions (at 1130 and 1428) ejected ash clouds to 1,000 m above the summit. A third explosion was noted at 0140 the next day, but no additional activity was observed during the 14-15 May journey from the volcano.

Information Contacts: H. Gaudru, SVE, Switzerland; G. de St. Cyr, T. de St. Cyr, and I. de St. Cyr, A.V. Lyon, France; T. Vaudelin, Genève, Switzerland.

April 1993 (BGVN 18:04) Cite this Report

Small gas and ash explosions

IV noted an increase in activity . . . in mid-March 1993, after a short period of repose, when explosions in the central crater sent an ash-and-gas cloud 1-2 km above the summit. On 15 March, volcanic tremor was noted, increasing in amplitude after 15 April.

A significant increase in seismicity beneath the volcano 24-27 April was reported by IVGG. Observers reported a glow near the summit area during the night of 25-26 April. A snowstorm prevented observation of the volcano 28-29 April, as volcanic tremor continued. Small steam and ash bursts inside the crater rose 200-300 m above the rim on 6 May. The plume extended 40 km NW from the volcano. Volcanic tremor remained above background.

IVGG reported three ash explosions from the summit crater on 10 May between 2030 and 2045, producing a plume that rose ~1 km above the crater rim and extended 7 km about SE. That same day, tremor amplitude measured by IV reached a maximum of 2.4 µm. Occasional steam and ash bursts occurred in the summit crater again 14 May; the plume rose 0.5-1 km above the crater rim and extended 1-7 km SW. Tremor amplitude had decreased by 19 May.

IV geologists note that tremor at Kliuchevskoi is common and is related to eruptive activity in the summit crater and, to a lesser degree, to flank eruptions. Tremor amplitude is largely dependent on the style of volcanic activity: amplitudes <0.5 µm are associated with steam-gas emission; 0.5-3 µm with Vulcanian explosions; and >3 µm with Strombolian explosions or lava spouting. Aircraft observations on 4 April 1993 revealed a newly formed crater at the summit with a diameter of 500 m and a depth of 200 m. A July 1992 overflight by S. A. Fedotov (IV) had previously revealed the almost complete subsidence of the 1984-90 cone. The last episode of dome collapse followed by renewed dome growth took place during 1962-68 when a new small volcanic cone was seen on the floor of the crater and minor lava fountaining was observed from its vent.

Information Contacts: V. Ivanov and V. Dvigalo, IV; V. Kirianov, IVGG

May 1993 (BGVN 18:05) Cite this Report

Seismicity continues; small explosions

Seismicity decreased in May . . . , returning to background levels by 21 May. Seismicity rose above background again on 1 June, when a few steam and ash bursts reached 400 m above the crater rim with a plume drifting to the S. A geologist from IVGG climbed to the crater rim that same day and observed a small explosive eruption from a growing cinder cone in the central crater. All volcanic bombs fell back into the crater, and no lava flows were present. Volcanic tremor was continuing as of 10 June, and there have been rare volcanic earthquakes at depths of >=10 km.

Information Contacts: V. Kirianov, IVGG.

June 1993 (BGVN 18:06) Cite this Report

Lava fountaining and explosive ash eruptions

On 19 June at 1100, a gas-and-ash burst generated a plume that rose 800 m above the crater rim, extending 20 km NW. Seismicity increased in late April before decreasing again in May, and remained at background levels in June. By 5 July, the level of volcanic tremor had increased significantly. Lava fountains, characteristic for this volcano, were observed rising 400 m above the crater rim on the night of 4-5 July. Late in the evening on 9 July, 10-12 lava bursts/minute were producing a lava fountain 100-400 m above the crater rim. Sporadic volcanic tremor was also recorded during the week of 5-12 July. On 13 July at 2345 gas-and-steam bursts produced a dark, ash-laden plume that rose 1 km above the crater rim and was blown SE. Lava fountaining to heights of 100-400 m above the crater rim was also observed.

Although ground observations of the summit were obscured by clouds on 15 July, the level of seismicity indicated that lava fountaining was occurring, possibly to heights up to 1 km above the crater rim. Gas-and-steam bursts that day were also producing a dark, ash-laden plume that, based on seismicity, may have risen several kilometers above the crater rim. Volcanic tremor was registered at seismic stations 11 and 19 km from the volcano.

An explosive eruption on 15 July at 1445 sent an ash cloud to an approximate altitude of 7.8 km. Satellite imagery later that evening showed multi-layered cloudiness E of the Kamchatka Peninsula, but no distinct ash plume. There were no pilot reports of ash after 1640, and one report indicated no ash above 6 km. Multi-layered cloudiness without a definitive ash cloud persisted on satellite imagery through 0700 on 16 July. A second eruption around 1500 on 16 July sent ash to 6 km. Satellite imagery did not detect a definitive ash cloud by 2500, and there were no pilot reports of ash between 7.5 and 11 km altitude.

Information Contacts: V. Kirianov and S. Zharinov, IVGG; J. Lynch, SAB.

July 1993 (BGVN 18:07) Cite this Report

Gas-and-ash plumes; lava flows down W slope; high seismicity

Steam-and-ash explosions . . . continued in late July and early August. A gas-and-ash plume was rising as high as 3 km above the crater (8 km altitude) and extending to the NW at 1400 on 25 July according to visual observations made from a helicopter by S. Zharinov and O. Braitseva. Lava flows were observed to extend from the summit crater down the W slope of the volcano, entering and melting the glacier at ~3,000 m elev. Seismic activity, including tremor, was stable but at a high level. The direction and height of the plume was about the same the next day as seen from a helicopter, and ashfall took place in Kliuchi [(30 km NNE)]. On 27 July at 2200, the gas-and-ash plume was as high as 5 km above the crater, extending to the S for an unknown distance. A W-flank lava flow was observed at 0030 on 28 July as well as lava fountains 600-700 m above the crater. On July 29 at 1500, the gas-and-ash cloud was 5 km above the crater and extended SW.

Airborne observations in early August indicated that the gas-and-ash plume was generally 1-3 km above the crater, extending to the N or NW for ~50 km. On 3 August, the gas-and-ash plume, as observed from a helicopter by V. Dvigalo and A. Belousov, rose to 6-7 km altitude and extended to the E in the afternoon and to the N that night. Lava continued to flow down the W slope of the volcano, and ash fell again on Kliuchi. Volcanic tremor remained high and steady in late July and early August.

Information Contacts: S. Zharinov, IVGG.

August 1993 (BGVN 18:08) Cite this Report

Gas-and-ash plume persists; lava flow stops

The summit eruption . . . continued, but the volcano was obscured by clouds 6-12 August. On 13 August, the gas-and-ash plume rose 200 m above the crater. By 20 August, lava had stopped flowing from the crater. That same day, the gas-and-ash plume reached a height of 500 m above the crater and extended ~2 km SE. Reports of a flank eruption were investigated on 8 September, but no new eruptive activity was found. On 9 September, the gas-and-ash plume rose 200 m above the crater and extended SE for ~15 km. Within the summit crater, eruptive outbursts occurred throughout the day. Seismicity decreased in early August, but increased again in early September, when constant volcanic tremor was registered.

Information Contacts: V. Kirianov, IVGG.

October 1993 (BGVN 18:10) Cite this Report

Gas-and-ash plumes, minor seismicity, and weak fumarolic activity continues

Activity continued through early November with minor seismicity, weak fumarolic activity, and gas-and-ash plumes rising at least 200 m. On 11 September, a gas-and-ash plume was as high as 200 m above the crater, and extended NE for ~1 km. Constant volcanic tremor was registered in mid-September, but other seismicity was at background levels. A gas-and-steam plume rose to 400 m above the crater rim and rare shallow tectonic earthquakes occurred under the central crater area during the week of 7-14 October. A small seismic event (possibly related to a small explosion) was noted on the afternoon of 21 October. On 6 November observers noted a gas-and-steam plume rising 300-500 m above the crater rim, directed to the SE for ~30 km. Weak fumarolic activity in the crater continued through 6 November, with seismicity near background levels.

Information Contacts: V. Kirianov, IVGG.

November 1993 (BGVN 18:11) Cite this Report

Low seismicity; 15-km-long plume in early December

Due to bad weather and poor visibility, monitoring . . . relied heavily on seismic observations. Through November and December the reported duration of tremor ranged from several hours/day (for the weeks ending 26 November and 4 December) to "background levels" (for the week ending 18 November). During the first week in December observers saw a gas-and-steam plume 500 m above crater rim, it was blown W and visible for a distance of ~15 km. Several other plume observations confirmed persistent degassing as late as the week of 22 December.

Information Contacts: V. Kirianov, IVGG.

December 1993 (BGVN 18:12) Cite this Report

Spasmodic tremor and temporally coincident shallow earthquakes

Spasmodic tremor and temporally coincident shallow earthquakes of amplitude <= 0.7 µm were recorded on 30-31 December at several seismic stations in the vicinity of Kliuchevskoi and Bezymianny volcanoes. A lack of seismic stations hampered precise estimates of location and the resolution of which volcano was closer to the focal points. The observed pattern of seismic activity was judged more characteristic of Kliuchevskoi. In addition, on 3 January another swarm of shallow earthquakes accompanied by spasmodic tremor was recorded near Kliuchevskoi's NE slope. Scientists use a color code to characterize the level of concern about volcanic activity. To indicate increased concern at Kliuchevskoi the color was shifted from green to yellow on 4 January indicating restlessness. For the week ending on 12 January, tremor at Kliuchevskoi prevailed for 7-9 hours a day, and shallow earthquakes took place 2-4 times/day.

Information Contacts: V. Kirianov, IVGG.

January 1994 (BGVN 19:01) Cite this Report

Weak volcanic tremor at variable levels; fumarolic activity

Weak volcanic tremor (5-9 hours/day) and shallow volcanic earthquakes (5-12 events/day) were recorded during the third week of January. Volcanic tremor increased in late January to nearly continuous levels (19-21 hours/day), although the number of shallow volcanic earthquakes decreased (1-6 events/day). High volcanic tremor levels continued into early February (16-22 hours/day), but had declined by 10 February to 0.3 hour/day. Tremor increased again slightly the following week (10-16 February) to 0.6-1.3 hours/day; 1-3 volcanic earthquakes/day were registered during that period. Weak fumarolic activity continued in the central crater throughout January and early February.

Information Contacts: V. Kirianov, IVGG.

March 1994 (BGVN 19:03) Cite this Report

Weak seismicity and fumarolic activity continue

Weak volcanic tremor (0.6-1.3 hours/day) and 1-3 volcanic earthquakes/day were registered in mid-February. During late February and early March, weak tremor continued and the number of seismic events increased slightly (2-5/day). Weak volcanic tremor was consistently registered for 1-3 hours/day throughout March, although it was slightly higher (<=4.5 hours/day) during the third week. Shallow volcanic earthquakes were more variable, ranging from 2 to 18 events/day. Seismic activity during the last week of March included both deep (3-13 events/day) and shallow (1-2 events/day) earthquakes, as well as weak volcanic tremor (4.5-6 hours/day). Weak fumarolic activity from the central crater was observed throughout most of March, and on 29 March a plume extended ~1 km above the crater.

Seismicity continued to increase in the first half of April, consisting of weak deep and shallow earthquakes (4-37 events/day) and weak volcanic tremor (0.5-6 hours/day). Weak fumarolic activity was observed in the central crater on 1-4 and 13 April, and the gas-and-steam plume reached as high as 800 m above the crater.

Information Contacts: V. Kirianov, IVGG.

April 1994 (BGVN 19:04) Cite this Report

Weak fumarolic activity, seismicity, and tremor

Seismic stations continued to register both deep and shallow weak earthquakes (average of 6 events/day) and weak volcanic tremor (0-1.5 hours/day) through the end of April. On 29 April there were 11 events/day, but the number of events decreased to 4/day by 5 May. Weak volcanic tremor decreased to 0.1-0.3 hours/day. Seismicity increased during the second week of May when 11-18 earthquakes/day were recorded. As of 18 May, both deep and shallow earthquakes (8-22 events/day) and weak volcanic tremor were continuing beneath the volcano. When the volcano was not obscured by clouds, weak fumarolic activity above the crater was observed in late April and May with a steam plume to <=1 km above the crater.

Information Contacts: V. Kirianov, IVGG.

June 1994 (BGVN 19:06) Cite this Report

Phreatic explosions; variable seismicity continues

Deep and shallow earthquakes, as well as volcanic tremor, continued to be recorded beneath the volcano in late May, June, and early July. In late May, between 13 and 44 events/day were recorded. The duration of volcanic tremor increased from 2.5 hours/day on 28 May to 21 hours on 30 May, but then decreased again to 2 hours on 31 May. During the first half of June, 5-20 weak, intermediate-depth earthquakes/day were detected; average duration of volcanic tremor increased from 16 to 24 hours/day during this period. This approximate level of activity continued through 25 June. In the last week of June, the number of weak intermediate-depth earthquakes increased to 18-46/day, but average tremor duration decreased to 0.3-1 hour/day. In early July, weak intermediate-depth earthquakes were recorded at a rate of 14-36/day; tremor was in the 14-24 hours/day range.

Weak fumarolic activity from the central crater was observed throughout June and early July. A steam plume on 10-11 June, possibly caused by a phreatic explosion, rose from the NW slope (2,500 m elev) to ~4,500 m altitude. A phreatic explosion on 15 June from the NE slope produced a plume that rose 2-2.5 km.

Information Contacts: V. Kirianov, IVGG.

August 1994 (BGVN 19:08) Cite this Report

Eruption sends gas-and-ash bursts at least 3 km high; lava fountaining

An eruption began on 8 September with lava fountaining and ash plumes that rose to an altitude of at least 8 km on 12 September. Explosive activity increased on 30 September, and on 1 October the ash column rose to >15 km altitude.

During 7-24 July, seismic stations continued to register weak intermediate-depth (10-30 km) earthquakes under the volcano (15-55/day); the duration of volcanic tremor averaged 8-22 hours/day. Weak fumarolic activity from the central crater was observed during the week of 7-14 July. Clouds frequently obscured the volcano through mid-August, but British climbers who visited the summit in early August reported no unusual activity. Seismicity increased from 24 July to 2 August, when 15-149 weak intermediate-depth earthquakes were recorded each day, accompanied by 1-20 hours/day of volcanic tremor. The number of weak intermediate-depth events decreased again during the next three weeks to 8-37 earthquakes/day. Tremor averaged 5-10 hours/day through 11 August, 3-4.5 hours/day the following week, and 5-17 hours/day by 2 September. Weak intermediate-depth earthquakes decreased from 2 to 8 September, averaging only 1-4 events/day. However, volcanic tremor was recorded for an average of 19-22 hours/day. Normal fumarolic activity was observed from the central crater early in September.

Seismic data indicated that an eruption began from the central crater at about 0400 on 8 September. Lava was observed fountaining 200-300 m above the crater from two separate vents. Gas and ash outbursts to 1 km were recorded every 10 minutes. Pilots from American Airlines reported an ash cloud as high as 11 km above sea level around 1445 on 9 September, and at 1010 the next day the cloud was reportedly moving SE at the same altitude.

On 12 September ground observers reported that the eruption sent gas and ash to 1.5 km above the crater. The ash plume reached an estimated 3 km above the 4.7-km-high volcano, to an altitude of ~8 km. The plume extended to the NE for more than 50 km and ashfall was reported in Kliuchi, [30 km NNE]. A 1-km-long lava flow was observed on the SW slope of the volcano; mudflows were also noted. Continuous volcanic tremor was recorded as far as 65 km from the volcano.

Kliuchevskoi was obscured by clouds on 13 September, but gas and ash explosions on 14 September rose 600-800 m above the crater with an ash column extending to 2 km above the crater. The ash plume was carried E for at least 50 km. A new lava flow 1.5 km long was observed on 14 September issuing from two NW-flank vents ~200 m below the crater rim. This flow is in addition to the lava flow on the SW flank of the volcano. Lava fountains were again observed extending to 200 m above the crater rim. Continuous volcanic tremor, with a maximum amplitude of 6.3 µm, was recorded at distances of 11 km from the volcano.

Information Contacts: V. Kirianov, IVGG; J. Lynch, SAB.

September 1994 (BGVN 19:09) Cite this Report

Eruption sends plume to 15-20 km altitude and produces lava flows

During 15-19 September, gas-and-ash bursts rose 500-700 m above the crater. The eruption column reached 1.5-2.0 km above the crater and extended >50 km downwind to the SE. Lava flows extruding from two vents 200 m below the crater rim had moved down to 2,800 m elevation on the NW and SW flanks. Phreatic explosions were occurring at the contact of the NW lava flow and the glacier. Lava fountains in the central crater reached heights of 300-500 m. Continuous volcanic tremor, with a maximum amplitude of 6.1 µm, was recorded at the seismic station 11 km from the volcano.

From 20 to 23 September, gas-and-ash bursts increased in height to 800-1,000 m above the crater. The eruption column continued to reach ~2 km above the crater, but extended >100 km SE. Lava flows on the NW and SW flanks remained active, and fountains in the central crater increased to heights of 500-700 m. Volcanic tremor was continuous with a maximum amplitude of 8.2 µm.

Eruptive activity increased on the afternoon of 30 September. Ash bursts rose 3 km above the crater and the ash column reached an estimated altitude of 10 km and extended SE for >100 km. Lava flows on the NW and SW slopes of the volcano remained active, and mudflows were noted on the N slope. Continuous volcanic tremor had a maximum amplitude of 8.4 µm.

At 0600 on 1 October the eruption entered a paroxysmal stage with lava bursts rising 4,500 m above the crater rim. The ash column was estimated at 15-20 km altitude and extended >100 km SE. Phreatic explosions along the margin of the flank lava flows generated steam clouds >1 km high. Avalanches of incandescent blocks were observed descending the N slope. Between 0900 and 1100, ash and lava bursts produced a dark, ash-laden plume rising to a height of 15-18 km and moving ESE. GMS satellite imagery showed ash ~565 km SE moving at ~140 km/hour. By 1400 the dark ash plume reached 15 km altitude. Lava and ash explosions continued from the central crater at 1500, when the ash column rose to 12-14 km above sea level and moved ESE at an altitude of 10-11 km. Pilot reports indicated that the ash was at 9-11 km (FL300-370 = 30,000-37,000 feet). A 747 aircraft reported an ash encounter at 11 km altitude, but avoided the cloud by climbing to ~12 km (FL390). Helicopter observations at 1500-1700 revealed two lava flows on the N and NW slopes and lava fountaining to 900 m above the crater rim. The eruption appeared to reach its maximum intensity between 0600 and 1630. By 1900 the ash plume was at a maximum altitude of 9-11 km and drifting E for >100 km. Volcanic tremor was continuous with a maximum amplitude of 8.4 µm. Analysis of GMS infrared imagery at 2330 showed a thin concentrated plume extending generally SE, surrounded by areas of thinner ash.

After about 0530 on 2 October, layered weather clouds moving from the W had obscured the summit from GMS satellite observation, although the dissipating ash cloud could be seen SE of the volcano. At 0920 a dark ash plume rose to ~8.4-8.7 km altitude and drifted E, but by 1100 the plume was only rising to 6-7 km and drifting NNE. Areas of thick, moderate, and thin dispersing ash, E and S of the volcano beyond the obscuring weather clouds, continued to be tracked by satellite through 2030. By that time, the ash cloud was becoming more diffuse and harder to distinguish from underlying low-level clouds.

The volcano was obscured by clouds on 3 October. Volcanic tremor with a maximum amplitude of 1-2.5 Nm indicated that the eruption was continuing, but at a reduced rate. On 4 October, only fumarolic activity appeared to be occurring inside the summit crater and no incandescence could be seen at night. The gas-and-steam plume rose ~1 km above the crater and was directed S for ~5 km.

Meteor-3 TOMS overflew the eruption plume at 1347 on 1 October. Preliminary results showed an extended SO₂ cloud ~800 km long to the SE, with an approximate area of 150,000 km². Estimated cloud mass was 90 kt SO₂ +- 50%. A pass at 1520 on 2 October did not find an SO₂ cloud.

Information Contacts: V. Kirianov, IVGG; J. Lynch, SAB; I. Sprod, GSFC.

October 1994 (BGVN 19:10) Cite this Report

Eruption sends plume to 15-20 km altitude and produces lava flows

Activity had decreased by 4 October, and continued to decline the following week. Continuous tremor after 3 October and into early November had a maximum amplitude of 0.23-0.53 µm, registered 11 km from the volcano. On 5 and 7-9 October the volcano was obscured by clouds, but on 6 October the fumarolic plume from the summit crater rose ~600 m above the rim and was directed NE. Observers in Kliuchi [(30 km NNE)] reported decreased activity during 8-15 October. Gas-and-steam columns rising from two apertures at the summit reached 2,500 m above the crater on 10 October and 800 m on 14 October. Once again during clear weather a gas-and-steam column was seen rising 200 m above the summit crater on 17, 22, and 23 October and to 800-1,500 m on 18-20 October. During 27-29 October the column rose 200-800 m above the summit. The volcano was obscured by clouds from 30 October to 2 November.

Information Contacts: V. Kirianov, IVGG; AVO.

November 1994 (BGVN 19:11) Cite this Report

Moderate explosive eruption causes minor ashfall 30 km away

Although clouds obscured the volcano in early November, continuous tremor (maximum amplitude 0.1-0.3 Nm) was recorded, and 4-11 earthquakes/day were detected under the volcano except on 7 November, when 23 events occurred. On 10 November, a gas-and-steam plume seen from Kliuchi (30 km NNE) was directed ESE for ~1 km. An observer in Kliuchi saw a gas-and-steam plume on 12 November rising 1 km above the summit that extended ~10 km ENE. On 18 November, observers in Kozirevsk (50 km W) saw a gas-and-steam column rising 50 m above the summit crater. Seismicity on the 18th consisted of continuous tremor (maximum amplitude 0.24 µm), one weak deep earthquake, and 9 shallow events.

A moderate explosive eruption occurred beginning about 0400 on 23 November, based on interpretations of seismicity. The volcano was completely obscured by clouds, but as much as 0.5 mm of ash fell in Kliuchi. Thirteen strong and shallow earthquakes beneath the volcano between 0400 and 1200 had maximum amplitudes of 14.25 µm at a seismic station 14 km from the volcano, and were recorded at stations up to 70 km away; persistent volcanic tremor had a maximum amplitude of ~0.33 µm. Comparing the seismicity to that of 30 September-1 October, the ash plume may have reached an altitude of ~7 km.

On 24 November, observers in Kliuchi noted a vigorous gas-and-steam plume containing minor ash rising 1 km above the volcano and extending >30 km NE. Weak volcanic tremor (amplitude ~0.15 µm) and 22 shallow earthquakes were registered beneath the crater area. The next day, observers in Kozirevsk reported a gas-and-steam plume above the volcano. Continuous tremor was recorded ~32 km from the volcano, and 12 shallow earthquakes were recorded beneath the crater area. On 28 November, a gas-and-steam plume seen from Kliuchi rose 2 km above summit and extended 3 km SW. A vigorous gas-and-steam plume of unknown height was also seen from Kliuchi on the 30th, continuous tremor (0.4 µm) was recorded 11 km away, and 73 shallow earthquakes were detected as far as 70 km away.

Information Contacts: V. Kirianov, IVGG; AVO.

December 1994 (BGVN 19:12) Cite this Report

Small eruption in mid-January

During the week of 8-14 December, 3-14 shallow earthquakes/day and 1.5-8.0 hours/day of volcanic tremor were recorded, down from the previous week. No visual observations were made because of a snow storm in the area. No information was available for the second half of December because of the suspension of communications from KVERT.

While in Petropavlovsk in mid-January 1995, Tom Miller (AVO) reported a small eruption that occurred sometime between 0630 and 1830 on 14 January. Weather in the area was poor, but an ash cloud was observed at ~9 km altitude. Seismic data indicated a single eruptive burst and not a continuous eruption. Satellite imagery showed weather clouds cover the area. However, at 0857 on 14 January a short, narrow plume, ~35 km long, was very evident on satellite imagery blowing NE. The apex of this plume appeared to start at the SE flank of the volcano, but at 1 km resolution this is uncertain. A band 4 minus band 5 image showed a distinct plume.

Information Contacts: V. Kirianov, IVGG; AVO.

June 1996 (BGVN 21:06) Cite this Report

Normal seismic activity, but degassing persists

During 26 May-22 July, seismicity remained at normal background levels. Gas and steam plumes rose 50-300 m above the crater and extended up to 15 km downwind. Regular reports from KVERT (via AVO) resumed in June after funding problems in Russia halted communications in December 1994 (BGVN 19:11).

Information Contacts: Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA, b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA; Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia.

August 1996 (BGVN 21:08) Cite this Report

Background seismicity and noteworthy tremor

Seismicity remained at normal background levels in late July and August. Seismic activity at a depth of 20-30 km continued. Volcanic tremors were detected on 24-25 August at a distance of 11 km. The amplitude of tremors dropped four-fold on 26 August. Only usual fumarolic activity was observed. On 29-30 August a fumarolic plume reached 50 m above the crater.

Information Contacts: Tom Miller, Alaska Volcano Observatory (AVO), 4200 University Drive, Anchorage, AK 99508-4667, USA; Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia.

October 1996 (BGVN 21:10) Cite this Report

Seismicity above background; fumarolic plumes up to 1 km tall

Seismicity was a little above background levels for most of September. Small earthquakes were registered at a depth of 20-30 km beneath the volcano. Seismic activity returned to normal background levels during late September, October, and the first ten days of November. During this period, fumarolic plumes were commonly observed and extended as high as 1,000 m above the crater.

During late November seismic activity increased to above background levels with some tremor. On 13 November two swarms of shallow earthquakes were registered. At 1200 on 14 November, eruptive activity began. Surface observers estimated that gas-and-ash clouds rose to an altitude of 6,700 m and drifted WSW for 20 km. On 15 November explosions sent gas and ash to 600 m above the crater. A gas-and-ash plume extended to the ENE for ~15 km. On 16-17 November gas-and-ash explosions 400-600 m above the crater were observed with a plume rising 2-2.5 km above the crater and extending 30 km NE. During 18-23 November gas-and-steam plumes reached 150-200 m above the crater with a plume extending SE-NE for 10-20 km. During 25 November-1 December, observers in the vicinity could hear discrete explosions in the crater. On 28 November a gas-and-steam plume rose to 2,000 m above the volcano.

December 1996 (BGVN 21:12) Cite this Report

Above-background seismicity; ash-and-steam plumes up to 3 km tall

The seismicity at Kliuchevskoi remained above background levels during December and 1-20 January. Fumarolic plumes were observed during December rising 100-1,200 m above the volcano and extending 5-15 km downwind. On 28 December and 4 January, gas-and-steam explosions rose to 200-300 m above the crater, and plumes extended 10-20 km to the NW.

An increase in eruptive activity was first noticed at 1740 on 7 January 1997 from the town of Kliuchi, ~30 km NE of the volcano. An ash-and-steam plume was observed rising 2,500-3,000 m above the crater and extending 20 km SE. Seismic activity, while still elevated, did not show an increase. An AVO analysis of a satellite image taken early on the morning of 8 January indicated that the plume had subsided. On 9 and 11 January, gas-and-steam explosions, possibly with minor ash, rose to 300-700 m above the crater, and the plumes traveled 10-15 km to the W or SW. On 13-14 and 16 January gas-and-steam plumes reached a height of 300-600 m and extended 10 km E. On 15 January, a gas-and-steam explosion rose 1,200 m above the crater, and its plume moved 15 km SE.

Information Contacts: Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA; Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia.

February 1997 (BGVN 22:02) Cite this Report

Seismicity remains elevated; gas-and-ash plume to 4 km over crater

Seismicity remained above background during February and 1-24 March. On 6 March, the largest gas- and-ash plume of February and March rose ~ 4,000 m above the crater (~9,000 m above sea level). AVHRR satellite imagery acquired at 0119 and 0630 showed the eruption plume extending 25-40 km SE. Smaller gas- and-steam plumes were more common during these two months with plume heights extending 100-2,000 m above the crater. Most of these plumes contained gas and steam exclusively but occasionally included ash.

Information Contacts: Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA; Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia.

March 1997 (BGVN 22:03) Cite this Report

Continuous presence of gas-and-steam plume up to 4 km above crater

Seismicity remained above background during 24 March-25 April. The presence of a gas-and-steam plume was reported from 25 March to 13 April at a height variable between 50 and 500 m above the crater and drifting NE to SE with the prevailing winds. On 27 March the plume rose to 1,500-4,000 m and spread 70 km to the E, and on 2 April to 1,500-3,000 m, moving 50 km to the E.

Information Contacts: Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA; Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia.

September 1997 (BGVN 22:09) Cite this Report

Frequent gas-and-steam plumes; infrequent ash plumes; low seismicity

Although the volcano was often obscured by clouds, gas-and-steam plumes were frequently observed between mid-July and mid-October. On 14 July, a plume rose from two vents to a height of 50 m. Gas-and-steam plumes were seen on 21 and 25-26 July rising as high as 200 m above the summit. Similar plumes occurring on 1, 5-6, 21, and 27-29 August had variable heights of 50-600 m.

Gas and steam plumes were seen on 6, 8-12, 15-22, 25, 27-28, and 30 September, and 8-9 October, usually rising 50-100 m with some reaching 1,000 m. On 7 September an ash-rich plume rose at least 150-300 m above the summit crater. An ash-and-gas plume on 26 September rose 300 m and extended 8 km SE. Another plume of gas and steam on 27-28 September rose 300-600 m and extended 10 km ESE.

During most of July seismicity remained at background level, with the exception of an hour or more of intense activity on the 23rd. From 28 July through 29 September seismicity was above background level; seismicity was concentrated near the summit crater and at depths of 25-30 km between 25 August and 22 September. Volcanic earthquakes registered inside the crater on 1-4, 7, and 20 August. During 30 September-12 October seismicity remained at about background level.

Information Contacts: Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia; Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

November 1997 (BGVN 22:11) Cite this Report

Elevated seismicity during 13 October-1 December; gas-and-steam plumes

During 13 October-29 December, seismicity under Kliuchevskoi was above background level. During 13 October- 2 November the activity occurred at depths of 20-30 km, but during 3-16 November, hypocenters were concentrated both near the summit crater and at depths of 25-30 km. Volcanic tremor recorded on 10-16 November was followed by tremor under the volcano and earthquake hypocenters 25-30 km deep during 17 November-14 December.

Gas-and-steam plumes rose 100 m above the crater on 18, 25, and 30 October, and on 1-2, 17-18, 23, and 28 November. A gas-and-steam plume rose 70 m above the summit crater on 6-7 November; by 8 November the plume rose 1 km above the crater and extended 5 km NW. By 9 November, the plume returned to a more typical height of 50-100 m. On 11-12 and 14-16 November, gas-and-steam plumes rose 100-200 m. During 2-6 December a gas-and- steam plume rose 300-1,000 m and extended 5-10 km SE to SW. On 7 December, a fumarolic plume rose less than 300 m above the summit crater. A gas-and-steam plume rose 300-700 m above the summit crater and extended 3-10 km NE and SW on 8-9 and 12 December. On 23, 24, and 28 December, a gas- and-steam plume rose 100-300 m and extended 3-5 km SE to SW. A fumarolic plume rose 2 km above the volcano on 25 December.

The level of concern was upgraded to yellow from green during 3-16 November, indicating that normal activity could possibly change into an eruption. During 17-23 November, although seismicity continued above background, the level of concern returned to green. On 1 December, the level of concern was again upgraded to yellow but returned to green as of 15 December.

Information Contacts: Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk- Kamchatskiy 683006, Russia; Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

January 1998 (BGVN 23:01) Cite this Report

Earthquakes, tremor, and modest gas-and-steam plumes through early January

During 22-29 December, above-background seismicity prevailed under Kliuchevskoi. Gas-and-steam plumes rose 100-300 m above the crater on 23, 24, and 28 December; these extended 3-5 km from the crater, generally SE or SW. On 25 December, a gas-and-steam plume rose 2,000 m above the summit crater. Poor weather obscured observation on other days.

Volcanic tremor under the volcano caused the level of concern to be upgraded to yellow from green during 30 December to 5 January. The upgrade indicated that normal activity could possibly change into an eruption. On 30 December a plume rose 1,500 m and extended 3-5 km SE of the crater. During 31 December-2 January the plume returned to a height of 200-500 m. Poor visibility continued during 3-5 January.

On 6 January the level of concern returned to green where it remained until the end of the month. Despite persistent bad weather, gas-and-steam plumes were observed rising to typical heights of 50 m above the crater on 11 and 19 January. More such plumes were observed 21-24 January rising 100-300 m and extending 2-3 km SE or NE.

February 1998 (BGVN 23:02) Cite this Report

Earthquakes, tremor, and gas-and-steam plumes throughout February

Beginning at 0616 on 28 January and continuing until 1 March, seismicity at Kliuchevskoi was above background level. During 28 January-8 February, earthquakes registered at depths of 25-30 km under the volcano and were accompanied by volcanic tremor. Surface earthquakes accompanied by volcanic tremor were recorded during 9-22 February, and deep earthquakes were detected during 23 February-1 March.

Fumarolic plumes rose 1-3 km above the volcano on 27 January, 3 February, and 17 February. Gas-and-steam plumes rose 50-2000 m on 30 January, 4-5, 9, 11-15, 18-22, 24-28 February, and 1 March. The plumes drifted 1-10 km with prevailing winds.

March 1998 (BGVN 23:03) Cite this Report

Earthquakes and frequent fumarolic plumes

During 2 March-5 April, seismicity under the volcano remained above background level and earthquakes at 25-30 km depth were recorded. Surface earthquakes were detected on 14 March from 0040-0105.

Fumarolic plumes rose 50-100 m above the volcano on 5, 7, 10, 13-15, 16, 18-20, and 22 March. On 30-31 March, and 1, 3, and 5 April the fumarolic plume rose 50-400 m above the volcano and moved 3-10 km SE. A gas-and-steam plume on 12 March rose 200-1,000 m and traveled more than 5 km ESE. On 17 March, a gas-and-steam plume rose 2-3 km above the volcano and drifted 5-10 km SE.

April 1998 (BGVN 23:04) Cite this Report

Seismicity above background, various fumarolic plumes

During the period 13 April-25 May, seismicity under the volcano remained above background level and earthquakes at depths of 25-30 km were recorded. Fumarolic plumes rose 50-200 m above the volcano during 6-9, and 11-16 April. These plumes were seen to move 5 km to the SE of the volcano.

At 1608 on 17 April, a series of shallow earthquakes of up to M 2 were recorded. The following day there was no measurable activity. A series of strong, explosive earthquakes lasting up to 10 minutes was recorded as far as 70 km from the volcano on 22 April. Hypocenters of earthquakes recorded in late May were concentrated at two levels: near the summit crater and at depths of 25-30 km. Starting at 2300 local time 24 May, a series of shallow earthquakes in the M 1.5-2.0 range were recorded.

Fumarolic plumes were seen 50-500 m above the volcano on 24, and 26 April, although clouds prevented observation during most of the week 20-27 April. Plumes 50-100 m above the summit were recorded on 27-29 April, and 11 and 14 May. During 13-24 May, a fumarolic plume rose 50-100 m above the volcano and drifted 1-5 km S and SE. On 25 May the plume rose 50 m above the summit.

Information Contacts: Olga Chubarova, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia; Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

June 1998 (BGVN 23:06) Cite this Report

Fumarolic plumes; 43-minute-long series of earthquakes on 12 July

During the period 29 June-20 July, seismicity under the volcano remained near background levels. Hypocenters of earthquakes recorded through the period were concentrated at two levels: near the summit crater and at depths of 25-30 km. Shallow events predominated deeper ones. Beginning at 1749 on 12 July, a 43-minute series of shallow earthquakes was recorded. The color coded level of concern was raised to yellow on 20 July.

Fumarolic plumes rose to only 50 m above the volcano during 22-24 June, but rose 100-300 m during 29 June-2 July. Plumes rising to 100 m and extending a few kilometers to the S or SW were also seen on 6, 7, 11, 13, and 14 July. On other days the summit was obscured by clouds.

August 1998 (BGVN 23:08) Cite this Report

Gas-and-ash explosions during 23-25 July

During 27 July-1 September seismicity under the volcano was generally above background. Hypocenters of earthquakes were concentrated at two levels: near the summit crater and at depths of 25-30 km. Shallow events were more numerous than deeper ones. Clouds often prevented direct summit observations. The level-of-concern fluctuated between Yellow and Green throughout the period.

Beginning on the afternoon of 23 July gas-and-ash explosions occurred every 15-20 minutes. A plume rose 300-500 m over the summit. No unusual changes in seismicity were recorded until noon on 25 July, when earthquake numbers and energy abruptly decreased, and tremor amplitude increased. During the first two weeks of August, earthquakes were concentrated near the summit accompanied by weak tremor. On 19 August tremor decreased but the number of shallow earthquakes increased. No tremor was recorded after 21 August, but on 23 August there was a 23-minute series of shallow earthquakes.

Fumarolic plumes rose to only 50 m above the volcano on 2 August, but some rose to 100 m by 9 August. Plumes rising to 400 m and extending 10 km NE were seen on 18 August. No plumes were seen on 11 and 16 August. On other days the summit was obscured by clouds.

September 1998 (BGVN 23:09) Cite this Report

Explosions, ash 2-3 September raise concern to yellow alert

During 2-28 September, seismicity under the volcano was generally above background levels. Hypocenters were concentrated at two levels: near the summit crater and at depths of 25-30 km. Clouds often prevented observations.

On 2 September a fumarolic plume was observed during the daylight hours rising 50 m above the summit. Beginning at 2218 that day, a 33-minute series of explosive earthquakes was recorded, and at 2245 an ash explosion produced a plume that rose 4-5 km above the crater. On 3 September, scientists noticed that ash had been deposited in a 2-km-long zone on the NE slope. A plume of gas, with no ash content, rose 500 m above the volcano during 3-4 September, but had stopped by 5 September. Because of the increase in activity, the alert status was changed to Yellow, meaning more significant eruptions may occur.

No fumarolic plumes were seen during 8, 18, and 27 September, but plumes rising up to 100 m above the summit were seen during 13, 16, 17, 21, and 24 September. The alert color code returned to Green on 21 September, indicating normal activity.

October 1998 (BGVN 23:10) Cite this Report

Background seismic and fumarolic activity during October

During October seismicity under the volcano was generally above background levels. Hypocenters of earthquakes recorded through the period were concentrated at two levels: near the summit crater and at depths of 25-30 km. On 1, 14, 15, 18, and 19 October a fumarolic plume was observed during the daylight hours rising 50 m above the summit. On 9 October the plume rose to 100 m above the summit. No fumarolic plumes were seen on 30 September, 2, 3, 6, 11, or 16 October. Clouds prevented direct observation of the summit during the remainder of the month. The alert status remained "green" indicating normal activity through October.

December 1998 (BGVN 23:12) Cite this Report

Series of shallow earthquakes 23 December

During 7-27 December seismicity under the volcano was generally at background. Hypocenters concentrated both at shallow depths near the summit crater and at depths of 25-30 km. On 7 December a fumarolic plume rose 500 m above the crater and extended >10 km E. During 8-11 December a plume rose 50 m above the crater before moving 2-3 km SE and E. On 21 December the plume rose 100 m above the crater, extending 10 km NW. On most other days during December, the volcano was obscured by clouds.

Beginning at 2352 on 23 December a series of shallow earthquakes with magnitudes smaller than M 2 began to be recorded beneath the volcano and at distances of >100 km. At 0400 on 24 December the activity abruptly decreased, although remaining still slightly above background until 1000 that day. Satellite images obtained during and after this anomaly did not show large areas of airborne ash. The level of concern color code was increased to yellow.

January 1999 (BGVN 24:01) Cite this Report

Series of deep and shallow earthquakes

Elevated seismicity persisted through January. Background seismicity was concentrated near the summit crater and at depths of 25-30 km. Beginning at 1514 on 2 January, a series of shallow earthquakes began to be detected. These earthquakes prevailed until 13 January when a 22-minute series was recorded. At 0055 on 15 January a series of deep (25-50 km) earthquakes began. By the end of the month, seismicity had returned to background levels and the alert level was lowered from yellow to green.

Fumarolic plumes rising several hundreds of meters above the summit were seen on 8, 13, 14, 19, and 23-28 January. Some of these plumes were blown by winds as far as 20 km from the volcano. On many days during January direct observation was prevented by poor weather.

March 1999 (BGVN 24:03) Cite this Report

Elevated seismicity and large steam plumes continue through March

Elevated seismicity persisted through February and March. Earthquake hypocenters were concentrated at levels near the summit crater and at depths of 25-30 km. Visual observations were hindered by bad weather on many days. Because of increases in activity, the Level of Concern Color Code was changed to Yellow from Green and back three times during the reporting period.

Deeper earthquakes increased toward the end of 1-7 February, and fumarolic plumes rose several hundred meters above the crater during this week. On 5 February a gas explosion sent a plume 2,500 m above the crater. Earthquakes at both shallow and deeper depths continued through 25 February, as did the fumarolic plumes.

Fumarolic or steam plumes were observed during most of the period 15-30 March rising hundreds of meters above the summit before being blown about 5 km. At 1422 on 17 March satellite images showed a steam plume extending 40 km NE. On 20 March separate gas and steam explosions occurring at a rate of 2-3 per hour rose 500 m above the crater. A 17-minute series of earthquakes and tremor was recorded on 3 March and low-amplitude tremor began to be recorded again on 12 March. Between 1918 and 2137 on 20 March a series of near-surface M <1.6 earthquakes occurred.

May 1999 (BGVN 24:05) Cite this Report

Series of ash explosions and shallow earthquakes during May

Seismicity at Kliuchevskoi was above background levels during most of May. Earthquakes were concentrated near the summit crater and at depths of 25-30 km. On 29-30 April, a plume rose 200-400 m above the crater. An ash explosion began at 1330 on 1 May and on the evening of 2 May a fumarolic plume rose 2,700 m above the crater. During 3-5 May plumes rose 200-1,500 m above the crater before extending a few kilometers NE.

Short-lived explosive eruptions began at 1143 on 7 May, as seen from the nearby town of Klyuchi [(30 km NNE)]. Activity began with a powerful gas-and-steam blowout that became dark gray as ash mixed with steam rose above the summit. Ash explosions continued to occur every three minutes until the series ended abruptly at 1217. The height of the ash column reached 3,000 m and the plume extended 8 km NW. Authorities increased the color-coded warning level to yellow. Less vigorous gas-and-steam explosions, with plume heights of 400-700 m, occurred during the day at intervals of 7-10 minutes. At 1453 an ash-poor explosion column rose 2,500 m above the crater. Explosions were observed every 3-5 minutes with plumes 200-1,000 m above the crater during much of 8-9 May. A plume released on 8 May extended 30 km to the S and at 1230 on 9 May a plume rose 2,000 m above the crater. Moderate seismic and fumarolic activity returned and continued until the end of May.

July 1999 (BGVN 24:07) Cite this Report

May-August seismicity weak; traces of ash in emissions

During the period from 17 May to 9 August 1999, seismicity at the volcano was generally at or below background levels. Tremors and shallow earthquakes were registered occasionally, and earthquake hypocenters were concentrated near the summit crater. Gas-and-steam plumes containing ash occurred weekly, rising from a few hundred meters to as high as 2 km above the crater. Ash in these plumes dispersed in various directions to distances from 1 to 15 km (the latter on 18 June and extending to the S). On numerous days during this period, the volcano was obscured by clouds.

In one interval, starting on the afternoon of 28 May, a series of small (M 0.5) shallow earthquakes and tremor was recorded. Seismicity increased markedly on 30 May with a series of shallow earthquakes (M <2). This declined at 1122 on 30 May and remained at background levels. During the first half of July and again on 21 and 25 July, weak fumarolic activity was again observed at the summit.

During 12-18 July, seismicity rose above background as tremor and shallow earthquakes registered. On the morning of 12 July a gas-and-steam plume rose 200 m above the crater and extended up to 4 km. In the evening, a gas-and-steam plume with a mixture of light brown ash rose 1.5 to 2 km above the crater extending as much as ~5 km downwind.

November 1999 (BGVN 24:11) Cite this Report

Variable fumarolic plumes and episodes of increased seismicity

Highly variable activity continued throughout August-December 1999. Typical daily activity observed during clear weather consisted of a small fumarolic plume rising 50-200 m above the crater and extending a few kilometers downwind, usually E or SE. Seismicity was generally at background levels, consisting of shallow earthquakes with some periods of tremor. However, higher gas-and-steam plumes were frequently seen and two episodes of increased seismicity were detected. The volcano was frequently obscured by clouds.

Tremors and shallow earthquakes were registered during 9-15 August. Typical small fumarolic plumes were seen on 9-10, 13-14, 16, 21-26, and 28 August, and 2, 4-5, 7-8, and 12 September. On 30-31 August a gas-and-steam plume rose 500-1,500 m above the crater. On 15 September a gas-and-steam plume rose 600 m, and on 16 September the plume rose 200 m extending 5 km E. Mainly shallow earthquakes were registered from 19 September through 24 October. Gas-and-steam plumes rose up to 500 m during 19-26 and 28 September, and 3, 5, 7, 11, 20-21, and 24 October, extending as far as 5 km E or SE. During the afternoon of 15 October there was a 6.5-hour-long series of shallow earthquakes. On 22-23 October a fumarolic plume rose 700-1,000 m and extended 5-20 km to the E and SE.

Seismicity, consisting of shallow earthquakes and tremor, was above background levels during much of the period from 25 October until 17 December. Only small fumarolic plumes 50-300 m high were seen on 25 and 27 October, but on 26 October a plume rose 1,000 m above the volcano and extended 40 km NE. Small fumarolic plumes to 300 m extending 5 km SE were seen on 29-31 October and 4 November, with smaller typical plumes on 5, 7-8, and 10-11 November. Shallow earthquakes and volcanic tremor were recorded especially on 15, 21, and 25 November, when a gas-and-steam plume rose 1,000 m and extended more than 7 km NE. Typical smaller fumarolic plumes were seen on 12, 16, 18-19, 22-24, 26, and 28 November, and on 1, 3, and 10 December. On 29 November and 1 December gas-and-steam plumes rose 1,500 m above the volcano and extended more than 20 km SE. A fumarolic plume on 8 December rose 2,500 m.

During December 17-29 seismicity at the volcano returned to background levels. Small plumes were recorded on 17, 19-21, 25, and 28 December. Another plume on the 23rd rose 700 m.

April 2000 (BGVN 25:04) Cite this Report

Frequent fumarolic plumes, one to 10 km altitude on 30 January

This report covers the period January-April 2000. As of 28 April 2000, KVERT (Kamchatkan Volcanic Eruption Response Team) temporarily suspended operations because of a lack of funding. During most of this four-month period, seismicity at the volcano was at background levels, with shallow earthquakes and weak fumarolic activity accompanied frequently by fumarolic plumes. The plumes rose from 50 to 1,500 m above the volcano and extended in various directions as far as 10 km from the vent. The volcano frequently was obscured by clouds.

Twice during the reporting period, however, the activity level increased sufficiently so that the hazard level was raised from Green to Yellow. The first of these events occurred during 29 January-3 February when seismicity was above background levels with shallow earthquakes and tremor registered. On 29 January, a fumarolic plume rose 1,500 m above the crater extending 30 km to the SE. On 30 January and 1 February, a plume rose 50-500 m above the crater and extended up to 15 km S. According to reports from pilots of Northwest and Reeve Aleutian Airlines, and an observer from Alaska Volcano Observatory on the Reeve flight, a gas-and-steam plume was observed at 1440 on 30 January rising as high as 8-10 km altitude. On the morning of 3 February the volcano was quiet. According to visual reports from from Kliuchi (~30 km NE of the volcano) and pilot reports, a short-lived eruption at 1708 on 3 February sent an ash-poor plume to altitudes of 8-9 km; instruments measured an accompanying increase in seismicity. According to analysis of a satellite image at 1825 on 3 February the plume extended 40 km SSE and contained a large amount of water or ice.

During the subsequent week (4-10 February), seismicity continued above background levels and shallow earthquakes and tremor were registered. At 1815 on 8 February, seismic data indicated that a short-lived explosion probably occurred, because a series of shallow events were recorded. On 4-5 February, a fumarolic plume rose 200-500 m above the crater and extended 3-40 km W and SW.

During the period 11 February to 2 March, seismicity at the volcano returned to near background level accompanied by typical events noted earlier. But during 3-9 March, seismicity at the volcano increased again and the hazard level was raised again to Yellow. During this period, shallow earthquakes were registered. On 3-4 March a steam-and-gas plume rose 1,500 m above the volcano. On 5-7 March, a fumarolic plume rose 100-300 m above the crater. On 8 March, a steam-and-gas plume rose 1,000 m above the volcano extending 5 km to the NW.

Seismicity returned to background levels on 13 March and the hazard level was reduced to Green. This situation prevailed throughout the remainder of March and April. Shallow earthquakes, fumarolic activity, and plumes continued as in the earlier portion of the reporting period.

September 2000 (BGVN 25:09) Cite this Report

Seismic swarms, fumarolic activity, and gas-and-ash explosions

This report covers the period June-mid-October 2000. KVERT (Kamchatkan Volcanic Eruption Response Team) resumed operations at the beginning of June, after being shut down due to lack of funding. Reports indicated that fumarolic activity occurred through 23 June, sending plumes up to 700 m above the summit crater. The week of 23-29 June was entirely quiet, with no seismicity above normal or activity from fumaroles.

Weak fumarolic activity began anew on 2 July and continued to the middle of the month. A fumarolic plume rose 100-200 m above the volcano on 15-18 July, and extended 2-5 km to NW, W, and S. On 21 July, a M2 earthquake occurred, and at 0330 on 24 July, continuous volcanic tremor began. Strong tremor occurred from 1550 to 1730, but afterward returned to background levels although shallow earthquakes continued to be registered. No thermal anomaly was detected in satellite imagery during that time. On 28 July at 0815, residents in Kliuchi, a town 30 km NE of the summit, observed a short-lived explosive eruption that sent a gas-and-ash plume to 3 km above the volcano. The plume extended to the S, and increased seismicity occurred. The eruption caused KVERT to increase the Level of Concern Code for Kliuchevskoi to Yellow. At 0703 on 31 July, seismic data indicated that an even more vigorous short-lived gas-and-ash explosion occurred, because a series of shallow earthquakes was registered with a greater signal amplitude than those on 28 July.

Seismicity during the first week of August was above background levels with both shallow and deep earthquakes. Seismic data indicated a possible short-lived gas-and-ash explosion at 1047 on 8 August. Estimates of the plume height using seismic data suggest that it was no higher than the 28 July eruption. Shallow seismic activity was recorded during the middle of August, but no visual data were available because the volcano was largely obscured by clouds. KVERT decreased the Level of Concern Color Code from Yellow to Green on 18 August. At the end of August, weak fumarolic activity was observed above Kliuchevskoi's summit crater. On 29 August, a gas-and-steam explosion sent a plume 100 m above the crater and was blown SE.

The beginning of September was marked by heightened seismicity. A continuous fumarolic plume rose to a height of 50-100 m during 1-5 September. Fumarolic and seismic activity decreased on 6 September. On 11 September, another fumarolic plume from the summit crater rose 200-300 m. Activity diminished to weak fumarolic emanations a day later. KVERT recorded several shallow and weak seismic events on the night of 12 September, indicating a small gas-and-ash explosion. Kliuchi residents observed a darkened crater rim and a new zone of ashfall the next morning.

A fumarolic plume rose to 100-200 m above the volcano on the night of 16 September and into the next morning. Seismic activity increased significantly at 1230 on 17 September with a swarm of intense shallow earthquakes until 1300; these were registered at a station more than 130 km away. Although no volcanic activity was observed visually, the KVERT Level of Concern Color Code for Kliuchevskoi was increased from Green to Yellow. Seismic activity decreased in intensity for the rest of the week. Weak fumarolic activity occurred on 20-21 September, but otherwise the volcano was quiet.

On 22 September, the residents of Kliuchi observed a 500-m-high ash plume at 1715, which drifted toward the S. Fumarolic emissions during 22-27 September sent plumes up to 100 m above the summit. Seismicity was at background levels and the eruptions ceased for the remainder of the month, causing KVERT to decrease the hazard status back to Green on 29 September. Near-background level seismicity continued into October. Minor fumarolic discharges occurred into mid-October with no further significant volcanic activity.

April 2001 (BGVN 26:04) Cite this Report

Consistent gas-and-steam emissions; high seismicity

The following report covers the interval of 30 December 2000-10 May 2001, during which Kliuchevskoi had a maximum Level of Concern Color Code of Yellow. Since the previous report (BGVN 25:09), gas-and-steam plumes rose from the volcano throughout the entire report period. During 30 December 2000-1 February 2001, seismicity remained at background levels and fumarolic plumes rose up to 1,000 m. Strong shallow earthquakes were subsequently recorded on 4 and 18 February. Gas-and-steam plumes continued to rise and reached a maximum height of 1,200 m above the summit through 22 February.

Beginning during 22-24 and 27-28 February, episodes of weak spasmodic tremor were registered. Weak interrupted tremor continued during 2-29 March. On 4 March the Kamchatka Volcanic Eruptions Response Team (KVERT) reported a gas-and-steam plume with a maximum height of 1,000 m extending 10 km NE of the volcano. Satellite imagery detected the large plume and prompted the Tokyo Volcanic Ash Advisory Center (VAAC) to issue an ash advisory the same day despite no reported detection of ash by KVERT. From 1925 to 1940 on 15 March seismographs recorded an intense series of shallow earthquakes. Gas-and-steam plumes reached heights of 2,000 m during mid-March. At about this time KVERT raised the hazard level of Kliuchevskoi from Green to Yellow.

The level of volcanic tremor began to gradually increase again at 1000 on 7 April; a significantly high level of tremor occurred at 1300 on the same day. At 0717 on 8 April seismicity increased sharply with a swarm of shallow earthquakes (M ~ 2) accompanied by volcanic tremor. No eruptive activity was observed, and after 0900 activity decreased substantially. Similar low-level seismicity continued through 12 April, and KVERT decreased the volcano's hazard level from Yellow to Green following this date.

Elevated seismicity continued at 1259 on 13 April with a strong earthquake (M ~ 5) that occurred between Kliuchevskoi and Ushkovsky volcanoes at a depth of ~12 km. Aftershocks of this event (M <= ~ 4.2) continued to occur through 19 April. Small shallow earthquakes were also registered. During 20 April-10 May low-level fumarolic activity was prevalent with plumes that rose up to 1,500 m and background-level seismicity. KVERT maintained a hazard status of GREEN as of 10 May 2001.

June 2002 (BGVN 27:06) Cite this Report

Increased seismicity prompts KVERT to raise hazard status to Yellow

During mid-September 2001 through at least mid-June 2002 activity at Kliuchevskoi was characterized by brief periods of increased seismicity and minor surface activity. Earthquakes up to M 3 occurred (table 3) along with weak spasmodic tremor with a maximum amplitude up to 1.5 x 10^-6 m/s (table 4). Gas-and-steam plumes often accompanied the increased seismicity and were visible reaching up to 2.0 km above the crater (table 5).

Table 3. Seismicity at Kliuchevskoi during mid-September 2001 through mid-June 2002. Courtesy KVERT.

Date	Event	Magnitude
13 Sep 2001	Two earthquakes	M ~2 and ~1.7
01 Oct-02 Oct 2001	Eleven earthquakes	five M ~2, six ~1.7
18 Oct 2001	Series of large earthquakes within the edifice	--
26 Oct-09 Nov 2001	Series of earthquakes within the edifice and ~30 km depth	--
13 Nov 2001	Swarm of shallow earthquakes	~M 3
13 Nov-15 Nov 2001	150+ earthquakes	M 1.7
07 Apr 2002	Series of shallow earthquakes began	M 2.3
24 May-31 May 2002	Weak earthquakes at a depth of ~30 km	--
31 May-07 Jun 2002	~20 earthquakes/day at a depth of ~30 km	M 2.3
11 Jun 2002	~30 min series of shallow earthquakes	M 2.8
07 Jun-14 Jun 2002	22-48 earthquakes/day at a depth of ~30 km	--

Table 4. Tremor recorded at Kliuchevskoi during mid-September through mid-June 2002. Courtesy KVERT.

Date	Event	Magnitude/amplitude (µm/s)
20 Sep 2001	Volcanic tremor	0.15
21 Sep-22 Sep 2001	Volcanic tremor	0.23-0.21
23 Sep 2001	Volcanic tremor	0.28
24 Sep 2001	Volcanic tremor	0.4
25 Sep-26 Sep 2001	Volcanic tremor	0.23-0.27
27 Sep-29 Sep 2001	Weak, continuous volcanic tremor	0.22-0.32
01 Oct 2001	Intermittent weak spasmodic volcanic tremor	0.19
02 Oct-04 Oct 2001	Intermittent weak spasmodic volcanic tremor	0.30
05 Oct 2001	Continuous, spasmodic tremor	0.30
06 Oct 2001	Continuous, spasmodic tremor	0.18
09 Oct 2001	Continuous, spasmodic tremor	0.26
10 Oct 2001	Continuous, spasmodic tremor	0.51
11 Oct 2001	Continuous, spasmodic tremor	0.47
12 Oct 2001	Continuous, spasmodic tremor	0.51
13 Oct 2001	Continuous, spasmodic tremor	0.54
14 Oct 2001	Volcanic tremor	0.13
15 Oct-17 Oct 2001	Volcanic tremor	0.15-0.17
Nov 2001	Episodes of weak volcanic tremor	--
Apr-May 2002	Weak volcanic tremor	--
30 May 2002	Volcanic tremor	1.5

Table 5. Plumes visible at Kliuchevskoi during 13 September 2001 to 20 June 2002. Plumes were visible from Klyuchi town unless noted otherwise. Heights are above the crater. Courtesy KVERT.

Date	Time	Plume details
13, 17, 19-20 Sep 2001	--	Gas-and-steam plumes rose 50-100 m.
19 Sep 2001	--	Gas-and-steam plume rose 1.0 km and extended 20 km to the S.
23 Sep 2001	--	Gas-and-steam plume rose 100 m.
24 Sep 2001	1828	Possible gas-and-steam plume observed in satellite image.
01 Oct 2001	0810	Gas-and-steam plume up to 1.0 km extending 30 km to the NW.
01 Oct 2001	1150	Gas-and-steam plume up to 2.0 km extending 15 km to the NW.
01 Oct 2001	1400	Gas-and-steam plume up to 1.5-2.0 km extending 10 km to the W.
01 Oct 2001	1730	Gas-and-steam plume up to 800 m extending 5 km to the S visible from Kozyurevsk.
02 Oct 2001	~0830	Gas-and-steam plume up to 300 m extending 3 km to the S visible from Kozyurevsk and Klyuchi.
05 Oct 2001	0850	Gas-and-steam plume rose 300 m and extended 3 km to the S visible from Kozyurevsk.
05 Oct 2001	1200	Gas-and-steam plume rose 100 m.
10 Oct 2001	0815	Gas-and-steam plume rose 500 m and extended 5 km to the S.
12, 14, 16, 27-29 Oct 2001	--	Gas-and-steam plumes rose 50-100 m.
30 Oct 2001	--	Gas-and-steam plume rose 700 m and extended 5 km to the SE.
31 Oct 2001	--	Gas-and-steam plume rose 50-100 m and extended 5 km to the SE.
01 Nov 2001	--	Gas-and-steam plume rose 50-100 m.
02 Nov 2001	--	Gas-and-steam plume rose 50-200 m and extended 3 km to the SE.
06 Nov 2001	--	Gas-and-steam plume rose 50-200 m and extended 20 km to the NE.
08 Nov 2001	--	Gas-and-steam plume rose 50-200 m.
09 Nov 2001	--	Gas-and-steam plume rose 600 m.
11-13, 18 Nov 2001	--	Gas-and-steam plume rose 50-100 m.
19 Nov 2001	--	Gas-and-steam plume rose 700 m and extended 10 km to the SE.
21 Nov 2001	--	Gas-and-steam plume rose 500 m and extended to the SW.
09 Apr 2002	2038	Explosion sent a gas-and-steam plume with possible ash to 1.0 km.
06, 09-10 Apr; 24, 27 May 2002	--	Gas-and-steam plume rose 100 m.
31 May; 1-3, 6, 9 15-16, 20 Jun 2002	--	Gas-and-steam plume rose 100-300 m.

On 13 November a swarm of shallow M 3 earthquakes caused the Kamchatkan Volcanic Eruption Response Team (KVERT) to increase the Alert Level from Green to Yellow. According to a pilot's report, at 1315 on 19 November powerful fumarolic activity was observed. Seismicity decreased during the following days and on 23 November KVERT decreased the Color Code to Green. Seismicity remained at or near background levels with only slight increases in activity until 31 May when a series of earthquakes (up to M 2.3) was recorded in the volcano's edifice. As a result, the Color Code was increased to Yellow.

During 31 May-7 June ~20 earthquakes occurred daily at a depth of ~30 km (table 3). Overflight observations on 9 June indicated fresh ash on the volcano's slopes. The deposits were not accompanied by visually or seismically detected explosions. At the end of the report period, seismicity was slightly above background with a small gas-and-steam plume visible from nearby villages.

Information Contacts: Olga Chubarova, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia; Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

November 2002 (BGVN 27:11) Cite this Report

Above-background seismicity June-November 2002

During late June through early December 2002 seismicity fluctuated at Kliuchevskoi, but remained above background levels. Plumes were occasionally visible reaching up to 2.0 km above the crater (table 6).

Table 6. Plumes visible at Kliuchevskoi during mid-August through early December 2002. Plume heights are above the crater. Courtesy KVERT.

Date	Time	Plume details
16-18 Aug 2002	--	A gas-and-steam plume rose 500-1500 m, extended 10 km to the W and NW on 16 and 18 August.
19 and 21 Aug 2002	--	A gas-and-steam plume rose 50-150 m, extended 10 km to the SW on 19 August.
22 Aug 2002	0700 and 0820	According to visual observations from Klyuchi town, a gas-and-steam plume with ash rose 100 m.
22 Aug 2002	0830	Observers from Kozyrevsk village reported a gas-steam plume that rose 100 m and extended 15 km to the S.
22 Aug 2002	0718	An AVHRR image (band 2) showed a steam-gas (?) plume extending S.
01 Nov 2002	--	A gas-and-steam plume rose ~800 m and extended 10 km to the SE.
08, 09, 13 Nov 2002	--	A gas-and-steam plume rose ~100-900 m and extended 10 km to the E and SE.
17-18 Nov 2002	--	Gas-and-steam plumes rose ~1,000-2,000 m and extended 10-20 km to the W.
19-21 Nov 2002	--	Gas-and-steam plumes rose ~100-200 m.
03 Dec 2002	--	According to visual observations from Klyuchi, gas-and-steam plumes rose ~1,300 m and extended N and NE.
30 Nov and 01, 02, 04 Dec 2002	--	Gas-and-steam plumes rose 100-400 m and extended 10 km to the SE, E, W, and N.
03 Dec 2002	--	According to satellite data, a ~15 km gas-and-steam plume extended NNE.

Increased seismicity during November 2001 and May 2002 (BGVN 27:06) prompted KVERT to increase the Concern Color Code to Yellow. The Code was reduced to Green on 21 June. On 30 August KVERT reported that during the previous week ~10 earthquakes occurred at depths of ~30 km beneath the volcano. Small shallow earthquakes and weak spasmodic tremor were also registered during the week. No further reports were issued until early November 2002.

On 8 November 2002, KVERT reported that seismicity had reached above-background levels several times per month during 2002. Specifically, they reported high seismicity as follows: 8 days each month during June, September and October; 4 days in July; 7 days in August, and an unspecified number of times during early November.

The Concern Color Code was increased to Yellow on 14 November. Seismicity was above background levels during 8 November through at least 5 December (table 7).

Table 7. Earthquakes and intermittent spasmodic volcanic tremor measured at Kliuchevskoi during late August through early December 2002. Courtesy KVERT.

Date	Earthquakes per day (~30 km depth)	Intermittent tremor (in terms of geophone velocity)
30 Aug 2002	~10	--
01 Nov-07 Nov 2002	5-13	Up to 1.1-1.4 x 10^-6 m/s.
08 Nov-10 Nov 2002	5-9	--
11 Nov-13 Nov 2002	33-56	Slowly decreased from 1.6 x 10^-6 m/s to 0.75 x 10^-6 m/s during 8-12 November.
14 Nov-17 Nov 2002	Decreased from 26 to 9	0.6-0.7 x 10^-6 m/s during 14-16 November.
17 Nov-20 Nov 2002	9	1.1-1.3 x 10^-6 m/s.
28 Nov-01 Dec 2002	8-13	--
02 Dec-04 Dec 2002	24-33	--
28 Nov-05 Dec 2002	--	~0.8 x 10^-6 m/s.

Information Contacts: Olga Girina, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia; Tom Miller, Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

February 2003 (BGVN 28:02) Cite this Report

Seismicity above background levels; explosion and thermal anomaly

Seismicity was above background levels at Kliuchevskoi during 29 November 2002 through at least 4 March 2003. Tens of earthquakes per day were recorded, mostly at depths of ~30 km (table 8), and intermittent spasmodic volcanic tremor occurred. During December through February, gas-and-steam plumes generally rose up to 2 km above the crater. The Concern Color Code fluctuated between Yellow and Orange, but by the end of the report period remained at Yellow.

Table 8. Earthquakes recorded at Kliuchevskoi during 29 November 2002-28 February 2003. Courtesy KVERT.

Date	Earthquakes per day
29 Nov-04 Dec 2002	Up to 33
06 Dec-13 Dec 2002	12-24
13 Dec-20 Dec 2002	6-12
19 Dec-25 Dec 2002	6-9
26 Dec-03 Jan 2003	3-11
06 Jan-09 Jan 2003	10-23
10 Jan-12 Jan 2003	12-28
13 Jan-15 Jan 2003	33-35
31 Jan-07 Feb 2003	16-39
07 Feb-14 Feb 2003	17-30
13 Feb-19 Feb 2003	14-81
21 Feb-28 Feb 2003	10-14

Visual observations and video recordings from the town of Klyuchi revealed that a plume from an explosion on 24 December 2002 rose 4 km above the crater and drifted WSW. On 5 January 2003 a faint thermal anomaly, and probable mud flow down the SSE slope were visible on satellite imagery. According to KVERT, the thermal anomaly and mud flow indicated that a lava flow may have begun to travel down the SSE slope. A probable mudflow, seen on the SE slope on 7 January, may have emerged after a short explosion to the SE or E, or after powerful fumarolic activity in the crater. During the week of 26 February-4 March, gas-and-steam plumes rose to low levels and possible ash deposits on the volcano's SE summit were visible on satellite imagery.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia; Alaska Volcano Observatory (AVO), a cooperative program of a) U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), b) Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and c) Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

July 2003 (BGVN 28:07) Cite this Report

Gas-and-steam plumes June-August with occassional ash plumes

Eruptions continued at Kliuchevskoi during late 2002 through mid-2003, with typical plume heights estimated at several hundred meters and occasionally reaching ~2 km above the volcano (eg., early July and August 2003). Above-background seismicity prevailed during most or all the reporting interval.

The volcano (also spelled Klyuchevskoy) was last reported on in BGVN 28:02, and vol. 27, no. 11, issues discussing events through 4 March 2003. This report relies heavily on tabled data to convey observations from as far back as 3 December 2002, providing some further details during the 3 December-4 March 2003 interval of overlap with the earlier reports. The source reports came from the Kamchatkan Volcanic Eruption Response Team (KVERT) and were communicated via the Alaska Volcano Observatory (AVO). Table 9 summarizes recent plume observations, while table 10 summarizes recent earthquake and intermittent spasmodic volcanic tremor, basically above-background seismicity affiliated with ongoing eruptive unrest.

Table 9. Plumes visible at Kliuchevskoi during December 2002 through mid-April 2003. Courtesy KVERT.

Date	Plume details
30 Nov-2 and 4 Dec 2002	Gas-and-steam plumes rose 100-400 m above crater and extended 10 km SE, E, W, and N.
03 Dec 2002	Gas-and-steam plumes rose ~1,300 m above crater and extended N and NE (NNE ~15 km from Russian satellite data).
05, 09, 12 Dec 2002	Gas-and-steam plumes rose ~100 m above crater and extended 3-10 km E and SE.
10-11 Dec 2002	Gas-and-steam plumes rose ~1,500 m above crater and extended N and NE.
13-16, 18 Dec 2002	Gas-and-steam plumes rose ~100-800 m above crater and extended 5-10 km E and SE.
17, 19 Dec 2002	Gas-and-steam plumes rose ~1,000-1,500 m above crater and extended 10 km E.
19, 21, 23 Dec 2002	Gas-and-steam plumes rose ~1,000-2,000 m above crater and extended to E, S, and N.
24 Dec 2002 (0100 UTC)	Gas-and-ash explosion rose ~4,000 m above crater and plume extended WSW.
04 Jan 2003 (2125 UTC)	Gas-and-steam plume rose ~1,000 m above crater and extended 20 km NE.
05, 07, 09 Jan 2003	Gas-and-steam plumes rose 10 m above crater.
08 Jan 2003	Gas-and-steam plumes rose 1,000 m above crater.
11-13, 15 Jan 2003	Gas-and-steam plumes rose 50-300 m above crater (very narrow plume extended 30-50 km NNE from US satellite data).
24, 27 Jan 2003	Gas-and-steam plumes rose 1,000 m above crater and extended 10 km NE (24 Jan) and SE (27 Jan).
25-26, 28-29 Jan 2003	Gas-and-steam plumes rose 100-300 m above crater.
01-03 Feb 2003	Gas-and-steam plumes rose 100-300 m above crater (extended 30 km NNE from Russian satellite data).
04 Feb 2003	Gas-and-steam plumes rose 1,300 m above crater and extended 10 km NE.
09 Feb 2003	Gas-and-steam plumes rose 1,500 m above crater and extended 10 km N.
10 Feb 2003	Narrow gas-and-steam plume extending 25 km N.
11, 13, 18-19 Feb 2003	Gas-and-steam plumes rose 50 m above crater.
15-17 Feb 2003	Gas-and-steam plumes rose 1,000 m above crater.
22-26 Feb 2003	Gas-and-steam plumes rose 200 m above crater.
23 Feb 2003	Gray sector (perhaps ash deposits) showed up on MODIS satellite data from Russia on the SE part of summit.
05 Mar 2003	Gas-and-steam plumes rose 300 m above crater.
10-13 Mar 2003	Gas-and-steam plumes rose 50 m above crater.
16 Mar 2003	Gas-and-steam plumes extended 25-40 km W (from US and Russian satellite data).
18-19 Mar 2003	Gas-and-steam plumes rose 700-1,500 m above crater (extended less than 30 km W on 19 Mar, from US and Russian satellite data).
21-22 and 24-25 Mar 2003	Gas-and-steam plumes rose up to 300-1,000 m above crater and and extended 5-30 km in all directions (extended 30 km NNW on 21 Mar and 100 km NNE on 24 Mar, from US and Russian satellite data).
22 Mar 2003	Gas-and-steam explosions with ash-poor plumes that rose up to 200 m above the crater.
28-30 Mar, 02 Apr 2003	Gas-and-steam plumes rose up to 50-300 m above crater and extended in all directions 5-20 km (10 km NW on 28 Mar, from US and Russian satellite data).
05 Apr 2003	Gas-and-steam plumes rose up to 300 m above crater and extended 10 km E.
07 Apr 2003	Weak fumarolic activity observed.
15-16 Apr 2003	Series of ash plumes rose up to 300 m above crater and extended 10 km E.

Table 10. Earthquakes and intermittent spasmodic volcanic tremor registered at Kliuchevskoi during December 2002 through mid-April 2003. Courtesy of KVERT.

Date	Earthquakes per day (~30 km depth)	Intermittent tremor (in terms of geophone velocity)
28 Nov-01 Dec 2002	8-13	~0.8 x 10^-6 m/s.
02-04 Dec 2002	24-33	~0.8 x 10^-6 m/s.
05-12 Dec 2002	12-24	~0.5-0.7 x 10^-6 m/s.
13-19 Dec 2002	6-12	0.5-0.7 x 10^-6 m/s.
19-25 Dec 2002	6-9	~0.6-0.7 x 10^-6 m/s.
24 Dec 2002	--	Gas-and-ash explosion at 0010 UTC.
03-04 Jan 2003	9, 10	~0.5-0.7 x 10^-6 m/s.
05-09 Jan 2003	10-13; one M 1.75 earthquake	Increased from 0.55 x 10^-6 m/s on 5-7 Jan to 0.7 x 10^-6 m/s on 8 Jan.
10-12 Jan 2003	12-18	0.4-0.75 x 10^-6 m/s.
13-15 Jan 2003	33-35	0.4-0.75 x 10^-6 m/s.
16-23 Jan 2003	--	0.4-0.6 x 10^-6 m/s.
16-19 Jan 2003	Increased from 44 to 90	--
20-22 Jan 2003	Gradually decreased from 35 to 21	--
24-31 Jan 2003	10-22; 18 M 1.25 earthquakes	0.3-0.5 x 10^-6 m/s.
01-06 Feb 2003	16-39; 15 M 2.0-2.2 earthquakes	0.4-0.6 x 10^-6 m/s.
01 Feb 2003	--	1.26 x 10^-6 m/s from 0311 to 2400 UTC.
06-12 Feb 2003	17-30; 17 M 2.0-2.1 earthquakes	0.5-0.7 x 10^-6 m/s.
13-20 Feb 2003	14-81; six M 2.0-2.2 earthquakes	0.4-0.7 x 10^-6 m/s (on 14 Feb, continuous tremor increased to 0.9 x 10^-6 m/s).
20-27 Feb 2003	10-14; 16 M 2.0-2.2 earthquakes	0.4-0.6 x 10^-6 m/s (from 1140 UTC 26 Feb, continuous tremor increased to 0.95 x 10^-6 m/s).
28 Feb-06 Mar 2003	5-11; three M 2.0-2.2 earthquakes	0.5-0.8 x 10^-6 m/s.
06-13 Mar 2003	6-11; 12 M 2.0-2.2 earthquakes	0.5-0.8 x 10^-6 m/s (6-9 Mar)
10-13 Mar 2003	--	1.1-1.3 x 10^-6 m/s.
13-20 Mar 2003	7-9; seven M 2.0-2.1 earthquakes	0.5-1.5 x 10^-6 m/s.
14 Mar 2003	--	1.5 x 10^-6 m/s.
20-24 Mar 2003	6-9	--
20-26 Mar 2003	26 on 25 Mar, 41 on 26 Mar; 16 M 2.0-2.2 earthquakes	1.0-2.8 x 10^-6 m/s.
28 Mar-03 Apr 2003	24-63	0.7-1.4 x 10^-6 m/s.
04-10 Apr 2003	10-15; 14 M 2.0-2.2 earthquakes	1.5-3.7 x 10^-6 m/s.
15 Apr 2003	~70	Up to 4.0 x 10^-6 m/s.

Unrest continued during June 2003. Seismicity was above background and continuous spasmodic volcanic tremor tended to increase slowly and consistently. Earthquakes, both at 30 km and shallow depths, continued to register. The character of seismicity also indicated that weak gas-ash explosions possibly occurred. Table 11 summarizes thermal observations.

Table 11. Kliuchevskoi thermal anomalies and plumes observed via Russian and United States satellites, 2 June-11 August 2003. Courtesy of KVERT.

Date	Thermal Anomaly (pixels)	Comments
02 Jun 2003	--	Gas-and-steam plume rose 400 m above volcano.
03 Jun 2003	3	--
06-07 Jun 2003	--	Ash-poor plume extending S 30-80 km; explosions sent ash-gas plumes to 50-500 m above volcano.
07-08 Jun 2003	weak	--
09 Jun 2003	--	Ash on NNE flank.
13, 16, 19 Jun 2003	1-4	Four-pixel anomaly with max temp of 46°C in a background of -1°C; ash-poor plumes 50-500 m above volcano.
23 Jun 2003	3	Possible ash deposits on SE flank; gas-and-steam plumes to 50-700 m above volcano.
28 Jun, 02 Jul 2003	3	Ash-poor plumes to 100 m above volcano); separate and continuous ash plumes to 1,000 m above volcano; plumes extended to E.
04-06 Jul 2003	1-2	Gas-and-steam with ash-poor plume extending 100 km to ESE; separate ash explosions to 2,000 m above volcano.
15-16 Jul 2003	1-2	Separate or series ash explosions to 1,000 m above volcano; strong ash explosions to 2,000 m above volcano.
20-24 Jul 2003	1-4	Gas-and-steam plumes rose from 100-1,000 m above volcano and extended 15 km to SW.
27-29 Jul,01 Aug 2003	1-4	Temperature from 12 to 50°C in a background of -5 to 20°C; gas and steam plumes rose 500-700 m and extended 5 km SW.
01, 04-07 Aug 2003	2-6	Gas-and-steam plumes rose 800-2,000 m above volcano and extended to NW and, later, S.
09, 11 Aug 2003	2-3	--

Information Contacts: Olga Girina, Kamchatka Volcanic Eruptions Response Team (KVERT), a cooperative program of the Institute of Volcanic Geology and Geochemistry, Far East Division, Russian Academy of Sciences, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia, the Kamchatka Experimental and Methodical Seismological Department (KEMSD), GS RAS (Russia), and the Alaska Volcano Observatory (USA); Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), the Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and the Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

November 2003 (BGVN 28:11) Cite this Report

Ash explosions and Strombolian activity through early December

Significant activity from Kliuchevskoi continued throughout 1 August to 5 December 2003, so the hazard status remained at Color Code Orange. Activity included ash explosions that generated long plumes, Strombolian activity in the central crater, thermal anomalies seen in satellite imagery, relatively strong shallow seismicity, and continuous spasmodic tremor. Kamchatka Volcanic Eruptions Response Team (KVERT) reports obtained via the Alaska Volcano Observatory (AVO) provided detailed reports of significant daily activity that is summarized below.

Gas-and-steam plumes, sometimes with ash, were frequently seen rising above the crater to heights of less than 1,500 m. However, on some days plumes were seen rising as high as 2,500-3,000 m. Most of the plumes dissipated after reaching distances described as greater than 10 or 20 km downwind. Satellite imagery showed that on 8-9 September ash-and-gas plumes extended 172 km to SW and 153 km to W. Long ash plumes to distances of 18-63 km SE were seen on 4 October. During mid-October (12, 16, 17, and 18) gas-and-steam plumes reached distances of 25-70 km in many directions. On 24 October an airline pilot reported an ash plume at ~6,800 m altitude extending to the NNE. A gas-and-steam plume approximately 50-55 km long extending to the ESE was noted on 10 November, and another with minor ash extended ~40 km E on the 16th.

Strombolian activity at the central crater was detected on 26 August, when volcanic bombs rose up to 200 m above the crater and explosions occurred at intervals of about 5 minutes. More Strombolian activity was seen by observers in Klyuchi and Kozyrevsk on 25 and 30 September, 2-4, 6-8, and 10-11 October, and 9-10, 14-15, 21, 27, and 29 November. Thermal anomalies were detected every week by USA and Russian satellites, sometimes as large as 8-9 pixels.

Recorded earthquakes at 30-km depth usually ranged up to 9/day through early November, with up to 18/day the week of 1-7 August, and 30 on 3 October; magnitudes were 1.6-2.6. Continuous spasmodic tremor had geophone velocities below 8 x 10^-6 m/s until 4 October, when velocities increased into the 8-20 x 10^-6 m/s range. Geophone velocities dropped again to 5-11 x 10^-6 m/s during 22 November-2 December, then rose to 18 x 10^-6 m/s through 5 December. Large shallow seismic events (M 1.7-2.6) were first reported during the week of 11-17 October. Nine such events that week were followed by totals of 4, 22, 48, and 43 per week over the next month. Counts increased to 75 for the week of 15-21 November, 80 during 22-28 November, and 130 for the week ending on 5 December. Large numbers of weak shallow earthquakes (counts not reported) were also recorded every week.

December 2003 (BGVN 28:12) Cite this Report

2003 ends with ~3-km-tall steam plumes, M 2 earthquakes, tremor

Ash explosions and Strombolian activity was reported at Kliuchevskoi through early December 2003 (BGVN 28:11). KVERT reported that unrest continued at Kliuchevskoi over the month of December, with occasional and repeated explosions containing ash, gas and steam rising to 7-8 km altitude, and possible lava flows from the central crater. Seismicity was above background levels over the month. The alert level remained Orange.

Strombolian activity was seen from the town of Klyuchi on 7 December. At 1300 on 6 December an ash explosion up to 1 km above the crater was registered and, on the same day, a 3 km high gas-steam plume was evident. Gas plumes, possibly containing small amounts of ash, rose 100-500 m on 7-16 December, generally extending in various directions and visible to distances of 3-10 km. During this time satellites detected 1- to 9-pixel thermal anomalies. Strombolian activity was again noted from Klyuchi on 12 December.

During the week ending 12 December there were approximately 150 large shallow earthquakes of ML 1.2-2.25 and a large number of weak shallow earthquakes. For example, on 8 December, an earthquake of ML greater than 1.75 was registered at a depth of 5 km under the central crater. On 11 December, 3 earthquakes of ML 1.75-2.0 were registered at a depth of 3-6 km under the central crater. The number of earthquakes was similar during the week ending 19 December.

Tremor occurred often. An index of the tremor's size, reported in terms of relative velocity between the Earth and the seismograph's suspended mass (the ground motion), was 19-23 µm/s on 4-5 December, decreasing to ~ 6.7 µm/s on 9-10 December. On 12 December continuous spasmodic tremor had velocities of 2.5-9.2 µm/s. During the week ending 2 January, tremor had velocities of 2-4 µm/s.

During the week ending 26 December there were 135 large shallow earthquakes of ML 1.9-2.3 and a large number of weak shallow earthquakes were reported. On 19 December, one earthquake at a depth of 11 km and two earthquakes at a depth of 30 km below the central crater (ML less than 2.0) were registered. Continuous spasmodic tremor had velocities of 2.7-5.3 µm/s. Gas-steam plumes were seen rising up to 100 m above the crater on 22-23 December. The volcano was obscured by cloud at other times. A 1-pixel thermal anomaly over the volcano was registered by satellite on 23 December.

During the week ending 2 January 2004, the number of large (ML1.9-2.2) shallow earthquakes dropped to ~ 33, with a large number of weak shallow earthquakes. A 1-pixel thermal anomaly was registered on 26-27 December. On 27-29 December, gas plumes were observed rising up to 50-500 m above the volcano, but the volcano was obscured at other times.

April 2004 (BGVN 29:04) Cite this Report

Background seismicity March-April 2004; ash plumes on 8 April

Unrest at Kliuchevskoi continued, with occasional and repeated explosions containing ash, gas, and steam that rose as high as 7.8 km altitude during January-April 2004. The alert level remained at orange.

Strombolian activity was reported in the central crater on 11-12 January and may have occurred again during 22-26 January. Gas-steam plumes extended up to 15 km in various directions during the report period; although one containing small amounts of ash, extended 75 km to the SW on 25 January.

Table 12 presents seismicity reported by KVERT including the number of large shallow earthquakes, their local magnitudes (Ml), and the range of tremor velocity. Many weak, shallow earthquakes also occurred each week. In overview, seismicity stood above background until about March, when it dropped to background, remaining there through 29 April. After February, instrumental measure of tremor (tremor velocity, table 2) declined. The details on the number and magnitude of large shallow earthquakes (which on the week ending 6 February had risen to ~ 430 Ml 1.2-2.0) ceased being a reported topic after February, although these earthquakes continued to be mentioned as occurring. Beginning in late February, earthquakes at depths up to 30 km were reported in moderate number ("deeper earthquakes"; table 2).

Table 12. Weekly seismic activity at Kliuchevskoi recorded 9 January to 29 April 2004. Some changes in reporting practices shifted around the week ending 27 February. The depth cutoffs for the two earthquake categories (shallow vs. deeper) were not disclosed; -- means not reported; M_L refers to local magnitude, and M_L? signifies an unstated magnitude. Courtesy of KVERT.

Period ending	Seismicity level	Shallow earthquakes (number/local magnitude)	Deeper earthquakes (daily number/magnitude/depth in km)	Tremor velocity (µm/s)
09 Jan 2004	above bkgd	~115 / 1.9-2.3	--	4-8
16 Jan 2004	above bkgd	~175 / 1.9-2.5	--	7-8 (11-13 Jan); 15-20 (12-15 Jan)
23 Jan 2004	above bkgd	~130 / 1.9-2.3	--	6-13
30 Jan 2004	above bkgd	~130 / 1.9-2.3	--	3-16
06 Feb 2004	above bkgd	~430 / 1.2-2.0	1-5 / M_L = 1.2-2.0 / 3-6	1-2
13 Feb 2004	above bkgd	~225 / 1.25-2.0	1-5 /M_L less than 2.25 / 3-6	0.5-1
20 Feb 2004	above bkgd	~135 / 1.25-1.7	1-6 / M_L = 1.25-1.85 / 3-6	0.4-0.9
27 Feb 2004	above bkgd	~160 / 1.25-1.75	~2 / M_L = 1.25-2.25 / 3-7; 22-25 Feb: ~7 / M_L? / 30	0.4-0.6
06 Mar 2004	slightly above bkgd	--	26-7 Feb: 6 / M_L = 1.25-2.2 / 3-7; 26 Feb-1 Mar: ~2 / M_L? / 30	0.2-0.5
12 Mar 2004	at bkgd	--	38 / M_L = 1.25-1.6 / 30	0.2
19 Mar 2004	at bkgd	--	~7 / M_L = 1.2-1.7 / 30; 11-14 Mar: 1 / M_L = 1.5-2.0 / 3-7	0.2-0.3
26 Mar 2004	at bkgd	--	~2 / M_L = 1.25-1.6 / 30; 25, 26, 30 Mar: 1 / M_L = 1.2-2.1 / 3-12	0.2-0.4
02 Apr 2004	at bkgd	--	26, 28, 30 Mar: 1 / M_L = 1.2-2.1 / 3-12; 25, 26, 30 Mar: ~2 / M_L = 1.25-1.6 / 30	0.2-0.4
09 Apr 2004	at bkgd	--	~3 / M_L = 1.25-1.85 / 30	0.2-0.4
16 Apr 2004	at bkgd	--	~10 / M_L = 1.25-1.8 / 30	0.2-0.4
22 Apr 2004	at bkgd	--	~8 / M_L = 1.25-1.7 / 30	0.2-0.4
29 Apr 2004	at bkgd	--	~5 / M_L = 1.25-1.75 / 30	0.21-0.25

Gas plumes frequently rose as high as 5.8 km altitude each week, with gas plumes rising 5.8-7.8 km altitude during 24-25 January. Seismic activity continued to be above background level throughout January and February (as it was in December 2003, BGVN 28:12), but in mid-March, seismic activity returned to background levels and remained there through April. Ash explosions and plumes rising to 4.9-5.8 km altitude occurred during January but none were reported subsequently, although satellite data indicated an ash plume extending N-NE on 8 April. US and Russian satellites reported weak thermal anomalies (1-7 pixels) during January and February, but no anomalies were reported subsequent to 20 February. Weak fumarolic activity was reported weekly after mid-March.

Information Contacts: Olga A. Girina, Kamchatka Volcanic Eruptions Response Team (KVERT), a cooperative program of the Institute of Volcanic Geology and Geochemistry, Far East Division, Russian Academy of Sciences, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia, the Kamchatka Experimental and Methodical Seismological Department (KEMSD), GS RAS (Russia), and the Alaska Volcano Observatory (USA); Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), the Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and the Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

March 2005 (BGVN 30:03) Cite this Report

Strombolian eruptions and lava flows during January-March 2005

From April to November 2004, the hazard status (Concern Color Code) remained at Yellow, with seismicity at background levels throughout this time, and occasional fumarole activity. Around 26 November 2004, the status was reduced from Yellow to Green, the lowest level. During November 2004, seismicity remained at background levels. Gas-and-steam plumes were seen up to 5 km altitude on 24 November 2004 and weak fumarolic activity was observed on several days. Kliuchevskoi was last reported on in April 2004 (BGVN 29:04) and this report covers the interval through 31 March 2005.

On 14 January 2005 the Kamchatkan Volcanic Eruption Response Team (KVERT) raised the status at Kliuchevskoi from Green to Yellow as seismic activity at the volcano increased. On 12 January, around 21 shallow earthquakes of M 1.0-1.7 and weak volcanic tremor were recorded. According to visual observations, weak gas-and-steam plumes were noted during 6-8 and 12 January. The plumes extended E from the volcano on 7 January and SW for 5 km on 12 January.

On 16 January 2005 KVERT raised the status again, from Yellow to Orange, as seismic activity increased significantly. During 13-14 January, 15 shallow earthquakes of over M 1.25 were recorded, along with an increase in the amplitude of volcanic tremor. Visual observations on 14 January noted a weak gas-and-steam plume that extended N from the volcano. Satellite data showed a bright thermal anomaly over the summit on 15 January.

During the third week of January, the total number of shallow earthquakes continued to increase. Gas-and-steam plumes rose to ~ 800 m above the lava dome. Incandescence was visible in the volcano's crater on several nights.

Strombolian eruptions occurred during 20-23 and 27 January. Explosions sent volcanic bombs 50-300 m above the crater on several nights. Gas-and-steam plumes rose to a maximum height of 1.5 km above the crater. On 21 January a gas-and-steam plume with small amounts of ash extended as far as 23 km NE of the volcano. Throughout January seismicity was above background, with a large number of shallow earthquakes recorded daily. Gas-and-steam plumes that rose to ~ 1 km above the volcano's crater drifted SW on 29 January and NW on 31 January. A small amount of ash fell in the town of Klyuchi, about [30 km to the NNE], on 31 January.

On 1 February around 1000, a mudflow carrying large blocks and trees traveled ~ 6 km down Kliuchevskoi's NW flank into the Kruten'kaya River. The mudflow reached a height of a few meters and trees were covered with mud to ~ 1.5 m. On 6, 8, and 9 February, ash plumes rose ~ 2.5 km above the volcano's crater. Gas-and-steam plumes rose to ~ 3 km during 6-9 February. A cinder cone was noted in the volcano's crater on 6 February. Fresh ash deposits were seen on the SW flank of Ushkovsky volcano (NW of Kliuchevskoi) on 7 February, and in Klyuchi on 9 February.

Throughout the first week of February there were Strombolian eruptions in the terminal crater of Kliuchevskoi, and a lava flow traveled into Krestovsky channel on the volcano's NW flank. Phreatic bursts occurred in this channel when the lava contacted glaciers during 6-9 February and 12-13 February. Ash plumes rose ~ 3 km above the volcano's crater during 12-14 February. During 12-16 February, volcanic bombs were hurled 300-500 m above the crater, Strombolian eruptions occurred in the crater, and lava again traveled into the Krestovsky channel. On 16 February, a mudflow extended 27 km. According to a news report, a lava flow from Kliuchevskoi melted a large section of Ehrman glacier on 21 February 2005.

Moderate seismic and volcanic activity continued at Kliuchevskoi during 24 February to 4 March. On 24 February lava continued to travel down the Krestovsky channel. Strombolian activity during this time sent plumes to ~ 1 km above the volcano. Ash fell in the village of Icha, about 275 km to the SW on 26 February, and in Kozyrevsk, about 25 km to the W, on 1 March. Ash plumes were visible on satellite imagery on several days. During the first two weeks of March 2005, eruptions continued. Strombolian explosions occurred intermittently from a cinder cone in the summit crater. Lava flows extend from this cone down the NW flank. Occasional vigorous explosions from the summit crater and along the path of the lava flow produced ash plumes as high as 7-8 km and traveled many tens or hundreds of kilometers downwind. Ash-and-gas plumes rose up to 3.2 km above the crater on 10-16 March and extended up to 150 km in various directions. Ash fell at Kozyrevsk on 11 March. Strombolian bursts rose about 500-1,000 m above the summit crater. Two lava flows were observed on the volcano's NW slope on 15 March. Clouds obscured the volcano at other times. According to satellite data, a large thermal anomaly was registered at the volcano during the second week of March.

During 11-18 March, Strombolian explosions occurred intermittently from a cinder cone in the summit crater. Lava flows extended from this cinder cone down the NW flank. Occasional vigorous explosions from the summit crater and along the path of the lava flow produced ash plumes that reached as high as 7-8 km altitude and drifted many tens or hundreds of kilometers downwind. Seismicity was above background at this time. On 11-12 March ash-and-gas plumes rose to 3.2 km above the crater. Ash fell in the town of Kozyrevsk, 30 km to the W, on 11 March. Strombolian bursts rose 500-1,000 m above the summit crater. On 15 March two lava flows were observed on the NW slope. The amplitude of volcanic tremor was about 12-13 x 10^-6 m/s on 18-21 March and increased to about 46.0 x 10^-6 m/s on 22 March. From 1730 till 1900 on 23 March it was up to 62 x 10^-6 m/s.

On 24 March KVERT raised the hazard status to Red (the highest level) due to increased seismic and volcanic activity. A gas-and-steam plume containing ash rose to ~ 7.5 km altitude on 22 March and ~ 8.5 km altitude on 23 March, extending NW. Ash fell in the town of Klyuchi during 23-24 March. According to data from AMC (Airport Meteorological Center) at Yelizovo, 340 km S, an ash plume that rose to ~ 7 km altitude and extended 70-80 km to the NW was observed by pilots on 23 March. The amplitude of volcanic tremor decreased from 62 x 10^-6 m/s on 23 March to 26-22 x 10^-6 m/s on 25-26 March. Satellite data indicated a 2- to 6-pixel (through the clouds) thermal anomaly over the volcano throughout the last week of March. Ash-and-gas plumes extended from the volcano 35 km N and 80 km W on 25 March. Seismometers detected a great number of shallow earthquakes and 27 earthquakes of Ml = 1.5-2.1.

During about 27-28 March seismic activity at Kliuchevskoi decreased, leading KVERT to reduce the status to Orange. According to visual and video data during 27-28 March, a gas-and-steam plume containing some ash rose ~ 200 m above the crater and extended W. Ash-and-gas plumes rose to 2,500-3,000 m above the crater and extended SE on 28 March, and NE on 29 March. Incandescence above the summit crater was observed on 28 March. According to the data from the AMC at Yelizovo, an ash-and-gas plume rising about 2,000 m above the crater at 1420 on 31 March was observed by pilots. Ash-and-gas plumes extended 250 km SE on 28 March, 270 km NE on 29 March, and 100 km NW on 31 March.

Information Contacts: Olga Girina, Kamchatka Volcanic Eruptions Response Team (KVERT), a cooperative program of the Institute of Volcanic Geology and Geochemistry, Far East Division, Russian Academy of Sciences, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia, the Kamchatka Experimental and Methodical Seismological Department (KEMSD), GS RAS (Russia), and the Alaska Volcano Observatory (USA); Alaska Volcano Observatory (AVO), cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), the Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and the Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA.

June 2007 (BGVN 32:06) Cite this Report

Significant eruptive activity resumes in mid-February 2007

Increased seismicity and volcanic activity began in January 2005 and continued through at least March 2005 (BGVN 30:03), with Strombolian eruptions, lava flows, ashfall, lahars, and tall steam plumes. Activity was intermittent during April 2005 through January 2007, primarily consisting of variable seismicity. Significant volcanic activity began again in mid-February 2007, after which large ash plumes became frequent and lava flows were observed. From that time through early August 2007 there have been Strombolian eruptions, lava flows, mudflows, and some large (though not particularly high) eruptive plumes extending up to ~ 2,000 km from the volcano, though cloudy weather often blocked views of the summit.

The seismic network maintained by the Kamchatka Experimental and Methodical Seismological Department (KEMSD) lacks a calibration linking ash-plume height with associated seismic signal. Instead, visual and video data were typically used by ground-based observers. Some height estimates cited here were based on satellite observations and comparisons with ancillary observations such as atmospheric wind profiles.

Activity during April 2005-January 2007. According to the Kamchatka Volcanic Eruptions Response Team (KVERT), ash-and-gas plumes rose to 1 km above the crater the first week of April. Eruptive and seismic activity decreased significantly on 7 April 2005, but remained above background levels until 8-9 May. During 8-15 July, seismicity again increased. This heightened activity continued through 15-22 July, with spasmodic volcanic tremor, shallow earthquakes, and gas-and-steam plumes rising to ~ 5.5 km above the crater. Ashfall was noted in Kozyrevsk on 22 June. On 22 July a weak ash-and-gas plume rose to ~ 100 m above the crater. This activity decreased in late July and returned to background levels by 3-9 August 2005. Weak fumarolic activity continued.

During 9-16 September, seismicity again increased. During this week, the amplitude of volcanic tremor increased, and weak gas-and-steam emissions and a thermal anomaly were visible on satellite imagery. By the middle of October 2005, activity had again returned to background levels where it apparently remained until December 2006. During the middle of December 2006, KVERT noticed a slight increase in seismicity, with moderate fumarolic activity. A thermal anomaly in the crater was detected on satellite imagery on 14, 15, and 18 December.

Activity during February-July 2007. Eruptive activity began again on 15 February 2007. Strombolian activity was observed during 15-18 February that ejected bombs 300 m above the crater. Video data and observations between 16 and 22 February indicated gas-and-steam plumes with small amounts of ash rising to altitudes of 5.3 km and drifting SW and then E. A thermal anomaly at the summit was detected during 16-19 and 21 February. Based on information from KEMSD and satellite imagery, the Tokyo Volcanic Ash Advisory Center (VAAC) reported that eruption plumes during 22-23 February may have reached altitudes of 6.1 km and drifted E. A news article in RIA Novosti cited local scientists who mentioned that on 26 February ash particles up to 2 mm in diameter fell on the village of Klyuchi, about 30 km NNE.

Clouds inhibited visual observations during most of February and March, but satellite data disclosed a daily thermal anomaly of 1-11 pixels in the crater area. Strombolian activity was seen again during 21-22 March, with lava bombs being ejected typically about 50-100 m above the crater; bomb heights of 100-200 m were noted on 31 March. On 29 March lava flowed down the NW flank.

A 23 March news report from RIA Novosti paraphrased Alexei Ozerov of the Russian Academy of Sciences in the department of Volcanology and Seismology, saying that activity had increased sharply since 15 February 2007. The article went on to quote Ozerov, stating that "The size of the lava globs reaches several meters in diameter." Geophysicists also reported through RIA Novosti that lava flows interacting with snow and ice were producing powerful explosions and vapor plumes.

KVERT reported that seismicity continued at heightened levels during April and May 2007. Volcanism over this period included Strombolian activity, lava flows down the NW flank, fumarolic activity, mudflows, and frequent gas-and-steam plumes with a small amount of ash that rose to altitudes of 5.3-6.3 km. Intensified fumarolic activity during 15-18 April resulted in higher gas-and-steam plumes, to altitudes of 6.3-7.2 km, possibly containing ash.

An ash plume drifting E on 22 April reached 8.8 km altitude. KVERT reported continuing mudflows and phreatic activity at lava flow fronts on the NW flank where lava interacted with ice (figure 4). Mudflows and lava flows advanced on the NW flank the following week, and plumes containing ash rose to altitudes of 5.2-7.2 km. Thermal anomalies were seen at the summit throughout April. Similar activity continued during the first half of May. Residents in Kliuchi heard explosions during 3-6 May, and reported ashfall on 4 May. Ash plumes that rose to 9.7 km on 11 and 16 May drifted E and NE, respectively, and again caused ashfall in Kliuchi. On 18 May KVERT reported that deposits from a mudflow filled the Krivaya river.

Figure 4. Lava flows and mudflows on the NW flank of Kliuchevskoi, 22 April 2007. Courtesy of KVERT; photo by Yu. Demyanchuk.

Ash plumes during 18-22 May rose to 8.5 km altitude, and Vulcanian summit activity and phreatic bursts on the NW flank were observed from 22 to 24 May. Strombolian activity at the summit built a new scoria cone that was visible on the night of 22 May, along with incandescent lava flows down the NW flank (figure 5). Strong eruptions occurred on 26 and 27 May, sending plumes to 10.1 km altitude on the latter day (figure 6). Ash plumes continued to be generated over the next few days, but only rose to 5-7 km altitude. A new lava flow moved down the E flank on 31 May, causing strong phreatic bursts (figure 7).

Figure 5. Strombolian activity and a new scoria cone in the crater of Kliuchevskoi, 22 May 2007. Lava flows continued to move down the flanks. Courtesy of KVERT; photo by Yu. Demyanchuk.

Figure 6. Photograph of an eruption from Kliuchevskoi, 27 May 2007. The view is from Klyuchi, 30 km NNE. Three eruptions occurred on 27 May, with plumes rising to 6.7, 8.8, and 10.1 km altitude. Courtesy of KVERT; photo by Yu. Demyanchuk.

Figure 7. Photograph of Kliuchevskoi on 31 May 2007 showing an ash plume from the summit and a large steam plume rising from the E flank where lava flows were interacting with ice. Note snow line in the foreground. Courtesy of KVERT; photo by Yu. Demyanchuk.

Heightened seismic and volcanic activity continued throughout most of June, with Strombolian and Vulcanian summit eruptions. Frequent ash plumes were often visible on satellite imagery, with estimated altitudes of 4.5-10 km. Plumes extended ~ 300 km S and E the entire week ending 8 June, and ~ 400 km N, W, and S the week ending 22 June. Increased seismicity on 19 June was followed by plumes and ashfall in Kozyrevsk village. A large ash cloud, ~ 300 km in diameter, was observed on 20-21 June near Yelizovo airport, 340 km S. On 29 June, ash plumes drifted E more than 2,000 km, while on 30 June, they drifted at least 900 km SW, based on satellite imagery. A thermal anomaly continued to be detected in the crater. Seismic activity decreased during 29 June-6 July, but remained above background levels through 13 July. Ash plumes visible on satellite imagery during 2-11 July rose to estimated altitudes of 5-7 km and drifted in various directions.

During 13-20 July, KVERT reported that seismic activity had returned to background levels, although a thermal anomaly in the crater and some ash plumes and gas-and-steam plumes were still noted. The hazard status had been either Orange or Red since mid-February, but toward the end of July the Level of Concern Color Code was lowered from Orange to Yellow due to a decrease in seismicity and an absence of ash plumes during 17-20 July. In a 9 August update, KVERT indicated that seismic activity had remained a background levels during the previous week, although some volcanic tremor and a few shallow earthquakes were registered. According to satellite data, a thermal anomaly was noted on 4 August (the volcano was obscured by clouds on other days).

Information Contacts: Olga Girina, Kamchatka Volcanic Eruptions Response Team (KVERT), a cooperative program of the Institute of Volcanic Geology and Geochemistry, Far East Division, Russian Academy of Sciences, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/eng/), the Kamchatka Experimental and Methodical Seismological Department (KEMSD), GS RAS (Russia), and the Alaska Volcano Observatory (USA); Alaska Volcano Observatory (AVO), cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA (URL: http://www.avo.alaska.edu/), the Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA, and the Alaska Division of Geological and Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA; Tokyo Volcanic Ash Advisory Center, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); RIA Novosti, Russian News and Information Agency, 4 Zubovsky Bulvar, 119021, Moscow, Russia (URL: http://en.rian.ru/).

March 2009 (BGVN 34:03) Cite this Report

Eruption in 2007 changed summit crater; ongoing 2008-2009 lava flows

Significant eruptions resumed in mid-February 2007. Our last report on Kliuchevskoi (BGVN 32:06) chronicled activity during April 2005-July 2007. This report covers the period from August 2007 to April 2009.

An eruptive period from February to July 2007 reached peak intensity on 29 June 2007 (BGVN 32:06). The ash column was sustained and reached an estimated 8 km high during an 8 hour interval. Plumes reached 2,000 km long. This energetic eruption produced substantial changes to the summit morphology, including removal of the cinder cone on the floor of the summit crater, leaving a deeper crater there. This followed a pattern of earlier substantial morphological change in the summit region during the interval 1968-2007.

Figure 8 shows the pattern of changes during 1968 to mid-2007, but does not show events beyond the time of the 29 June 2007 eruption. Alexey Ozerov (Institute of Volcanology and Seismology, IVS) flew over the volcano during August 2007 and was the first to observe that, following the large eruption, the cinder cone was gone and the crater floor had dropped to an extent that the crater had developed an open capacity of 0.5 km³. The earlier events shown on figure 8 documents over 600 m of vertical change in the position of the crater floor or the tops of cinder cones on the floor.

Figure 8. A plot showing the height of the crater floor and intra-crater cones at Kliuchevskoi during 1968-2007. The date of the 29 June 2007 eruption was added by editors, but the extent of post-eruptive topographic changes is not shown. Symbols at the top describe eruption types; crater floor elevation was measured at the dots. After Zharinov and Demyanchuk, 2008.

Activity during 2008. Preceding the next eruption, increasing seismic activity and thermal alerts were seen during June to October 2008. On 7 August the color code was raised from Green to Yellow due to increased earthquakes and intermittent tremor. A thermal anomaly was registered over the volcano.

Beginning on 8 October observers noted an explosive-effusive summit eruption that included mainly Strombolian activity. On that day the color code was raised to Orange.

During October-November 2008 analysis of satellite imagery revealed a thermal anomaly in the crater. Lava began filling the crater. Nighttime observers saw the crater rim glowing and lava fountains at least 300 m tall. Extensive lava flows developed by late October (figure 9). From 28 October to 4 November bursting sounds from the volcano were heard in Klyuchi, about 30 km to the NE.

Figure 9. Strombolian eruption and associated lava flow down the NW flank seen at Kliuchevskoi on 31 October 2008. Photo by Yuri Demyanchuk.

On 21 November 2008, lava flows advanced on the NW slope. They descended to 3 km elevation. Gas-and-steam plumes drifted 80 km NW on 24 November and 20-40 km SE during 25-26 November.

The mostly active period continued from late November 2008 to early January 2009. During 28 November-10 December, Strombolian activity ejected bombs 500 m above the crater and lava effusion on the NW flank continued. Analysis of satellite imagery revealed large daily thermal anomalies in the crater. On 8 December the front of the lava flow made contact with the thick portion of the Erman Glacier, causing phreatic bursts and mudflows (figure 10). A very similar process occurred during the 2007 eruption (BGVN 32:06), and the December line of descent was also the same as in 2007. During 8-10 December, ash plumes rose to altitudes of 7.5-8 km, and drifted about 700 km E.

Figure 10. Lava descending Kliuchevskoi's NW slope. Lava from the crater descended over glaciers and where ice was thick in mid-flank areas, phreatic eruptions occurred. Undated photo by Yuri Demyanchuk.

During the final phase of the eruption (16 January-16 April 2009) the magnitude of volcanic tremor rapidly decreased. The volcano generated ash plumes extending 80-90 km to the NE. Fumarolic activity was seen during last days of April (figure 11).

Figure 11. Crossing alpine snow fields at the foot of Kliuchevskoi, a dogsled team pauses as the mountain emits gas and steam plumes on 9 April 2009. Photo by Yuri Demyanchuk.

As noted by Zharinov and Demyanchuk (2008), Shirokov (1985) studied the timing of Kliuchevskoi's volcanic eruptions with respect to lunar cycles. He found that eruptions were associated with a Moon-Earth rotational cycle of 18.6 years duration. According the Zharinov and Demyanchuk (2008), Shirokov (1985) forecast an eruptive interval during May 2006-May 2009.

References. Shirokov, V.A., 1985, Some questions method forecast flank eruption at Kliuchevskoi (Kamchatka): Volcanology and Seismology, no. 6, p. 48-58 (in Russian).

Zharinov, N.A., and Demyanchuk, Yu.V., 2008, The summit eruption of Kliuchevskoi volcano in 2007 (Kamchatka): Conference proceedings, dedicated to the day of volcanologists, on 27-29 March, 2008, Petropavlovsk-Kamchatsky: Insitute of Volcanology and Seismology, Far East Division, Russian Academy of Sciences, p. 81-89 (in Russian).

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanology and Seismology (IVS), Kamchatka Branch of the Geophysical Service of the Russian Academy of Sciences (KB GS RAS), Far East Division, Russian Academy of Sciences, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Olga Girina and Yuri Demyanchuk, KVERT, Institute of Volcanology and Seismology (IVS); Alexei Ozerov, Active Volcanism Laboratory, Institute of Volcanology and Seismology (IVS).

June 2010 (BGVN 35:06) Cite this Report

Ongoing 2009-2010 eruptions; 243-km-long plume during February 2010

After about four months of quiet, eruptions from Kliuchevskoi in January and February 2010 included days with vigorous plumes as high as 6-10 km; a cinder cone grew also inside the active crater. The previous eruption, which began on 8 October 2008 and continued until 16 April 2009, was characterized by Strombolian activity, large thermal anomalies detected in satellite images, lava flows on the NW flank, and phreatic bursts from lava contacting the Erman glacier (BGVN 34:03).

During mid-April to August 2009, the volcano was quiet and exhibiting weak fumarolic activity. Two eruptions followed, one in August and another in September 2009. Precursors to the 17 August eruption included elevated seismicity and ash visible in fumarolic emissions. The 17 August ash plume was small and rose to only ~5 km altitude.

During 11-18 September 2009 seismicity remained at background levels, although weak tremor was detected. Satellite imagery revealed a weak thermal anomaly over the volcano from 13 to 17 September. Strombolian activity that ejected tephra 70 m above the crater was seen at night on 16 and 17 September. On 18 September observers in Kliuchi (~35 km NNE) saw glow from the crater. Similar activity, including lava flows that began in mid-November 2009, continued in late September through February 2010 (table 13). A daytime photo on 12 November showed an E-slope lava flow with dense white clouds of condensed gases above it; a night photo on 13 November of the same area showed glow from the flow reflected in the gas plume.

Table 13. Summary of eruptive behavior at Kliuchevskoi during September 2009-February 2010. Courtesy of KVERT.

Date	Tephra heights above crater	Other observations
16-17 Sep 2009	70 m	Preceded by IR anomaly during 13-17 September
28 Sep-10 Nov 2009	70-500 m	Strombolian emissions
12-15 Nov 2009	200 m	New lava flow traveled 500 m down the ESE side
20 Nov-31 Dec 2009	200-500 m	Lava continued to flow down the ESE side
02 Jan-03 Jan 2010	500 m	New lava flow on the NW flank (Krestovsky chute)
05 Jan 2010	500 m	Two lava flows, on the ESE and NW flanks
08 Jan-14 Jan 2010	--	NW lava flow had reached 1.2 km in length; phreatic explosions at the lava-flow front; periodic ejections
15 Jan-21 Jan 2010	300 m	Lava continued to flow NW; phreatic explosions from the front of the lava flow ejected material to altitudes of 4.5-8 km
22 Jan 2010	300 m	Ashfall in Kliuchi
23 Jan-11 Feb 2010	300-200 m	Lava flow seen on the NW flank
12 Feb-19 Feb 2010	200 m	Strong gas-steam plumes extended about 243 km to E
20 Feb-28 Feb 2010	300 m	Phreatic explosions from the NW-slope lava front

Seismicity, initially slightly above background levels in late September 2009 increased during the next month to include many earthquakes and weak to stronger tremor. Seismicity then remained above background levels for the rest of the reporting period.

Many Strombolian eruptions sent material well over the crater rim, and inside the crater they built a cinder cone. The tephra from these eruptions was ejected as high as 100 m above the crater initially in late September and early October, but then was ejected 200-300 m on average through much of the reporting period (table 13). Tephra rose 500 m above the crater at points during 16-22 October 2009 and during 24 December 2009-5 January 2010, but much higher plumes were reported by the Tokyo Volcanic Ash Advisory Center (VAAC) during early 2010. The longest plume reported occurred during 12-19 February 2010; it extended 243 km E. Lava flows remained active on the NW slope in January and February 2010 (figure 12).

Figure 12. Lava flows down the NW slope of Kliuchevskoi on 16 January (left, to 1.2 km) and 12 February 2010 (two flows, no distance given). Photos by Yuri Demyanchuk.

Lava flows first appeared on 14 November 2009 and traveled 500 m down the ESE flank. The flows continued to be active until early 2010. During 2-3 January 2010 a new lava flow descended the NW flank. Both the NW and the ESE flanks had active lava flows for a few days, until about 8 January at the latest, when the NW-flank lava flow became dominant. Notably, from 8 January through most if not all of February, phreatic explosions occurred at the front of the lava flow where it encountered ice and meltwater. The front was ~ 1.2 km down slope of its source by mid-January 2010.

Taller plumes. During 2009 and 2010 KVERT and the Tokyo Volcanic Ash Advisory Center (VAAC) noted some plumes up to ~ 5 km over the 4.8 km summit (i.e. plumes up to 10 km altitude). A brief mention of some representative plumes (both largely steam- and ash-bearing) follow. A gas-and-steam plume containing a small amount of ash seen during 5-9 December 2009. It rose to an altitude of 6.3 km and drifted E. During 12-14 January 2010 gas-and-steam plumes rose to an altitude of 6.8 km and drifted E. During 15-22 January, phreatic explosions from the lava-flow front ejected material that rose to altitudes of 4.5-8 km. Based on information from the Yelizovo Airport (UHPP) and satellite imagery, the Tokyo VAAC reported that during 18 and 22-23 January ash plumes rose to altitudes of 7-10 km and drifted N and NE. Ash fell in Kliuchi on 22 January. Gas-and-steam plumes rose to a maximum altitude of 6 km during 30-31 January and 8-10 February. Satellite imagery for the days 23 and 24 February 2010 revealed respective gas-and-steam plumes drifting 90 km NNW and 25 km ESE.

Seismicity. According to Gorelchik and Garbuzova (2001), seismologists identified earthquakes clustered in four regions at depth ranges of 4-5 km, 5-12 km, 12-20 km, and 20-40 km beneath the volcano. In the upper three regions seismologists noted primarily volcanic-tectonic earthquakes. These were presumably a result of a solid medium in those regions under the influence of continuously changing stress fields. Such fields are thought to be generated around subsurface pathways and features containing magma.

The deepest region, 20-40 km depths, generally corresponds to the lower horizons of the crust and transition into the mantle. At Kliuchevsoi, seismologists found this region to be an anomalous zone that generated many long-period earthquakes, events interpreted to result from magma migration. The diameter of the zone in the widest part was ~ 20 km and its center was shifted slightly NE of the crater. In some cases, earthquake foci migrated towards the surface starting from depths of ~ 25 km.

Reference. Gorelchik, V., and Garbuzova, V., 2001, Seismicity at Klyuchevskaya volcano as a reflection of it's modern igneous activity: Geodynamics and volcanism of the Kuril-Kamchatka island system (in Russian), IVGiG FEB RAS, Petropavlovsk-Kamchatsky.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanology and Seismology (IV&S) Far East Division, Russian Academy of Sciences (FED RAS); Kamchatka Branch of the Geophysical Service of the Russian Academy of Sciences (KB GS RAS), Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs, http://www.emsd.ru/~ssl/monitoring/main.htm); Yuri Demyanchuk, IV&S FED RAS.

July 2013 (BGVN 38:07) Cite this Report

Eruptions continue, 19 February 2010-15 November 2013

Kliuchevskoi (also called Klyuchevskaya and Klyuchevskoy) has been quite active for many decades. During January 2009-February 2010, the volcano experienced Strombolian activity, lava flows, vigorous plume emissions, and a growing cinder cone (BGVN 35:06). This report discusses activity from 19 February 2010 through 15 November 2013, based on reports from the Kamchatkan Volcanic Eruption Response Team (KVERT). A map of the Kamchatka Peninsula is provided in figure 13. A summary of plumes between 12 Feb 2010 and 14 November 2013 is provided in Table 14 which, because of its length, is near the end of this report.

Figure 13. Map of Kamchatka Peninsula showing location of Kliuchevskoi. Courtesy of Lost World, Ltd. (Travel Kamchatka).

Active period: 19 February to 4 November 2010. Seismic activity during this period was consistently above background levels, and the explosive-effusive eruption of the volcano continued. Almost every week, KVERT reported periodic Strombolian activity that ejected material 100-300 m above the crater. Ash plumes and gas-and-steam emissions were common events, with some plumes rising to altitudes as high as 10 km (table 14). Nearby communities such as Klyuchi (30 km NNE) experienced ashfall. Satellite images consistently revealed a large daily thermal anomaly at the volcano.

Lava flows descended the NW, S, and NE flanks until about 1 May 2010 when such flows apparently ceased for more than two months. However, ground observations were sometimes prevented due to meteorological cloud cover. A satellite image from 9 March 2010 showed that the S-flank flow was about 1.3 km long.

A news article (Itar-Tass) reported a new lava flow from a fissure on 8-9 July. According to KVERT, during 16-23 July 2010, an effusive lava flow began to descend the SW flank. In subsequent weeks, lava flowed down the SSE flank (23 July-5 August), SW flank (6 August-29 October), NW flank (3-10 September), and W flank (8-29 October). These flows continued until about 29 October 2010. Phreatic explosions sometimes occurred from the fronts of the lava flows. KVERT specifically reported such explosions weekly during 19 February-12 March 2010, and on 29-30 August 2010 and 5 September 2010.

According to KVERT, ash plumes were common (table 14) and ashfall in nearby communities were sometimes reported.

Between 19 February 2010 until about the last week of October 2010, heightened seismic activity was relatively consistent. On 23 October KVERT reported increased seismicity, characterized by an abrupt increase in volcanic tremor and explosive activity. The Aviation Color Code, which had been at Orange throughout the reporting period, was raised to Red on 23 October 2010 (table 15 defines KVERT's Aviation Color Codes). On 30 October explosive activity decreased along with the magnitude of volcanic tremor. The Aviation Color Code was lowered to Orange. (Table 15 indicates KVERT's Aviation Color Code levels.)

During 30 October through 3 November 2010, seismic activity was still above background levels. Strombolian activity was observed, and KVERT even reported Vulcanian activity that produced ash plumes rising to an altitude of 7 km. A news article (Associated Press) from 29 October stated that ash from Kliuchevskoi and Shiveluch caused area flight diversions. On 4 November, seismicity sharply decreased and only gas-and-steam activity was observed. The Aviation Color Code was lowered to Yellow. According to KVERT, the eruption that had begun in August 2009 had finally terminated by 4 November 2010, and that seismicity had continued to decrease.

Less active period: 5 November 2010 to 31 October 2013. KVERT reported that during 8 November to 17 December 2010, seismic activity at Kliuchevskoi was at background levels or slightly above. A weak thermal anomaly over the crater was observed in satellite images.

During 9-10 and 16-18 November 2010, KVERT observed strong fumarolic activity, and ash plumes and gas-and-steam plumes occurred periodically. Cloud cover frequently prevented observations. About 24 November 2010, the Aviation Color Code was raised to Orange, presumably due to daily strong fumarolic activity and an ash plume that rose 5 km on 24 November. Ash fell in Kozyrevsk (about 50 km W) on 27 November and in Klyuchi (30 km NNE) on 28 November 2010. Strombolian activity was observed during 1-2 December 2010.

According to KVERT, activity declined during 10-17 December 2010, and the Aviation Color Code was lowered to Yellow. Gas-and steam emissions were observed during 10-13 December. Clouds frequently obscured the volcano during December.

During 4-11 February 2011, KVERT reported that seismic activity, although moderate, had essentially decreased, and lowered the Aviation Color Code to Green around 10 February. Satellite images showed a weak thermal anomaly over the crater on 6 and 7 February.

During 2011, KVERT observed only periodic ash plumes (table 14). An ash plume on 29 May 2011 that rose to an altitude of 5 km prompted KVERT to raise the Aviation Color Code to Orange. However, the lack of further activity the next day prompted KVERT to return it to Yellow, and then Green. Moderate gas-and-steam emissions were observed on 30 May and 1 June; cloud cover prevented observations on the other days of the week.

Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that an eruption on 3 July produced a plume that rose to an altitude of 7 km.

The KVERT website has no reports on Kliuchevskoi between 10 February 2011 and the end of September 2012, other than the Aviation Color Code was Green. In October 2012, KVERT reported that seismic activity at Kliuchevskoi had been gradually increasing since June 2012. Episodes of volcanic tremor first detected on 21 June continued through 14 October. A weak thermal anomaly was detected in satellite images during 1 September-14 October, 23-26 November, and 7-8, 10, 12-13, 16 and 18 December (and possibly additional dates). Strombolian activity was observed at night during 13-15 October, 23-30 November, and 30 November-21 December. Clouds frequently hampered detection on other dates. During periods of Strombolian activity, crater incandescence and gas-and-steam emissions were also detected. KVERT raised the Aviation Color Code to Yellow in mid-October. According to KVERT, activity at Kliuchevskoi decreased in late 2012 (around the same time the Tolbachik eruption began).

KVERT weekly reports noted that during January to the middle of March 2013, weak-to-moderate seismic activity, Strombolian explosions, and weak-to-moderate gas-and-steam emissions continued. (Gas-and-steam activity was moderate-to-strong in late February.) During January, incandescence at the summit was occasionally observed and satellite data sometimes showed a weak thermal anomaly at the summit. Clouds obscured the volcano frequently. On 18 March the Aviation Color Code was lowered to Green.

KVERT issued no reports on Kliuchevshoi between 21 March 2013 and the middle of August 2013. Presumably, the aforementioned activity, with some Strombolian explosions, continued at a low level.

On 15 August, a new explosive eruption began, with renewed Strombolian activity. Video data showed incandescence at the summit at night, and gas-and-steam plumes containing a small amount of ash rose up to 5.5 km. Satellite data showed a large, bright thermal anomaly over the volcano during 15-17 August.

The moderate seismic activity and Strombolian eruption continued through early October 2013. Incandescence at the summit was observed at night, and gas-and-steam plumes containing a small amount of ash rose up to an altitude of 5.5 km. Satellite data showed a thermal anomaly over the lava dome during this time, except where clouds obscured the volcano. On 26 August, a new lava flow on the WSW flank was observed. By 26 September, four lava flows were observed on the NW, W, SW flanks (figure 14). On 1 October, satellite data showed an ash plume extending about 100 km to the ESE.

Figure 14. Photo of Kliuchevskoi on 27 September 2013 showing Strombolian activity and several lava flows on the NW flank. Courtesy of Yu. Demyanchuk, KVERT.

In early October 2013, seismic activity gradually increased, and on 6 October a sharp increase of tremor occurred. According to video data, a flank eruption around this time began at the pass between Kliuchevskoi and Kamen volcanoes (Kamen's summit is only 5 km SW of Kliuchevskoi's). Local incandescence and gas-and-steam plumes were observed from the pass, and video data showed incandescence at Kliuchevskoi's summit and the W flank at night, and gas-and-steam plumes containing ash. Strombolian activity continued and several lava flows traveled down the NW, W, SW flanks. Occasionally, phreatic-generated plumes were observed at the fronts of lava flows. Ash plumes rose to an altitude of 6 km during 9-10 October and minor ashfall was noted at Klyuchi Village. A large thermal anomaly was recorded.

By the middle of October, the increasing activity prompted KVERT to upgrade the Aviation Color Code to Red, the highest level. During 15-16 October, video data showed strong Vulcanian explosive activity, and an ash plume rose to an altitude of 10 km. Strong incandescence was observed at the summit and W flank at night. Strombolian activity, several lava flows, and phreatic plumes continued, with ash rising to 5 km and causing minor ashfall in nearby communities. Numerous lava flows on the SW flank and a probable flank eruption at the pass between Kliuchevskoi and Kamen volcanoes led to vigorous melting of Bogdanovich glacier; the resulting water increased the Studenaya River's flow, which then destroyed part of the road near Kozyrevsk village (about 50 km W).

During 18-20 October, the eruption peaked and was characterized by high seismic activity, strong Vulcanian explosions, lava flows, intense incandescence, and ash plumes that rose to an altitude of 12 km and extended in various directions. Strombolian activity continued with lava fragments ejected 500-800 m above the summit cinder cone. A photo of the volcano on 20 October 2013 is shown in figure 15.

Figure 15. NASA Earth Observatory photo of Kliuchevskoi taken on 20 October 2013 by the Operational Land Imager on Landsat 8. According to the caption (written by Adam Voiland and Robert Simmon), multiple lava flows streamed down Kliuchevskoi's N and W flanks. The top, false-color image shows heat from the flows in a combination of shortwave-infrared, near-infrared, and the green band. Ash, weather clouds, and steam appear gray, while snow and ice are bright blue-green. Bare rock and fresh volcanic deposits are nearly black. In the wider natural-color (red, green, blue) image, snow and clouds are white, the ash plume is light gray, and forests (with trees tall enough to stand above the snow cover) are dark brown. Courtesy of NASA Earth Observatory (images by Robert Simmon).

The eruption intensity decreased on 20 October, and on 30 October, KVERT lowered the Aviation Color Code to Yellow. However, moderate seismic activity and strong Strombolian activity persisted into at least late November 2013, along with several lava flows on the SW, SE flanks. In addition, KVERT video data showed strong fumarolic emissions and occasional ash plumes. Large thermal anomalies continued to be recorded.

On 18 November 2013, KVERT raised the Aviation Color Code to Orange, probably due to weak Vulcanian activity.

An airline crew flying NW of the volcano at an altitude of 13 km saw the resulting ash cloud and sent the following information to the Anchorage Air Route Traffic Control Center: "Ash cloud 30 miles [48 km] NW of PSN [position], ash cloud F430 [13 km a.s.l.] then it steps down F400 [12 km] then lower F340 [10 km] right toward Mt. Klyuchevskoy[.] Aircraft deviated 50 miles [80 km] east to get around ash cloud. Ash cloud appears to be decreasing." The crew also reported "ash fallout."

For reporting, the crew used the Volcanic Activity Reporting form (in Appendix 2 of the U.S. Federal Aviation Administration's Aeronautical Information Manual, 9 February 2012). The above-mentioned completed form was sent to the Bulletin's staff on 18 November. The International Civil Aviation Organization (ICAO) has proposed the use of a similar form. We encourage flight crews to complete one of these two forms when detecting an ash cloud and send it to the appropriate government agency; we also encourage U.S. and international government agencies to send these completed forms to us for use in preparing Bulletin reports.

Table 14. Plume characteristics during 12 February 2010-14 November 2013. Key: G&S is gas-and-steam, G&A is gas-and-ash, G&S (A) is gas-and-steam with a small amount of ash, -- is not reported. Frequently, cloud cover prevented observations. Data do not include low-rising emissions. Courtesy of KVERT, Tokyo VAAC, KEMSD, and Yelizovo Airport (UHPP).

Time period	Plume type	Max plume altitude (km)	Drift direction and length
12-19 Feb 2010	G&S	--	240 km NE
19-26 Feb 2010	G&S	--	25-90 km various
26 Feb-05 Mar 2010	G&S	6.8	50 km NE (3 Mar)
05-12 Mar 2010	G&S	5-6.8	80 km E
12-19 Mar 2010	G&S Ash	5 4.9	NE (21 Mar)
19-29 Mar 2010	G&S Ash	--	80 km E 75 km NE
26 Mar-02 Apr 2010	G&S (A)	5.3	70 km E (30 Mar)
02-09 Apr 2010	G&S G&S (A) Ash	6.3	30-180 km NNE 55-60 km NE
09-15 Apr 2010	G&S	--	85 km NE (9 Apr)
16-23 Apr 2010	G&S Ash G&S Ash	5.7 7.9	45 km S (18 Apr) 90-100 km E (20-21 Apr) W (27 Apr)
22-30 Apr 2010	G&S (A) Ash G&S	7.3	W, SW 65 km W (24 Apr) 55 km W, SW (24-27 Apr)
30 Apr-7 May 2010	Ash Ash G&S Ash?	5.5 6.1	125 km N (2 May) 70 km W (3 May) 55 km W, W (2-3 May)
7-14 May 2010	G&S (A) G&A Ash	6.1	21 km N
14-21 May 2010	Ash G&A G&S (A)	5.8	NE, 20-145 km E
21-28 May 2010	G&S (A) Ash Ash	5.5	185 km various (24, 26 May)
28 May-04 Jun 2010	G&S (A) Ash	7.3	40 km NW
04-11 Jun 2010	G&S (A) Ash	7.3	60-190 km NE
11-18 Jun 2010	Ash	5.5	40 km SE
18-25 Jun 2010	Ash	5.5	120 km various
25 Jun-02 Jul 2010	Ash	5.3	32 km S
02-09 Jul 2010	G&S Ash	5.3	76 km S
09-16 Jul 2010	G&A Ash	5.2-6.8	45 km NW various
16-23 Jul 2010	G&S Ash	6.3	55-160 km various
23-30 Jul 2010	G&A	--	145 km SW
30 Jul-06 Aug 2010	G&A	--	65 km NW
06-13 Aug 2010	G&A, Ash	--	--
13-20 Aug 2010	G&A, Ash	--	325 km SE
20-27 Aug 2010	G&A, Ash	7.6-10.4	200 km SE
27 Aug-3 Sep 2010	Ash	5.2-7	various
03-10 Sep 2010	Ash	5.5-6.5 km	150 km S, SW
10-17 Sep 2010	Ash	6-9.8	Various
17-24 Sep 2010	Ash	5.2-7	60 km W, 240 km E
24 Sep-01 Oct 2010	Ash	6.5-7	78 km W, 185 km E
01-08 Oct 2010	G&A, Ash	6.3	50 km SE
08-15 Oct 2010	G&S, Ash	5.8-10.1	90 km E
15-22 Oct 2010	Ash	6.5-7.5	420 km E, SE
22-29 Oct 2010	Ash G&S(A)	8-9 6.5	N, SE SE
30 Oct-03 Nov 2010	Ash G&S	5-7	E, SE
03-08 Nov 2010	G&S	--	--
08-19 Nov 2010	Ash G&S	--	40 km NE (13 Nov) 28 km NE
19-26 Nov 2010	Ash G&S	5-7.9	E 111 km NE
27 Nov-01 Dec 2010	Ash G&A	5.8-6.7 6.3	NE 430 km N, NE
01-09 Dec 2010	G&S	--	--
10-18 Dec 2010	G&S	--	--
20 Dec 2010	Ash	6.7	N
23-24 December 2010	G&S	--	--
25 Dec 2010-23 Jan 2011	--	--	--
24 Jan-03 February 2011	G&S	--	--
04-07 Feb 2011	G&S	--	--
30 Mar 2011	Ash	5.2	E
29 May 2011	Ash	5	SW
30 May-01 June 2011	G&S	--	--
06 June 2011	Ash	6.1	NE (Tokyo VAAC stated plume could have come from Bezymianny volcano)
03 Jul 2011	Ash	7	E
02-08 Nov 2011	Ash	6.7	(Tokyo VAAC stated plume could have come from Bezymianny volcano)
09 Nov 2011-09 Oct 2012	--	--	(KVERT did not issue reports on Kliuchevskoi during this time)
23-30 Nov 2012	G&S	--	--
30 Nov-07 Dec 2012	G&S	--	--
07-14 Dec 2012	G&S	--	--
14-21 Dec 2012	G&S	--	--
18-25 Jan 2013	G&S	--	--
15-20 Aug 2013	G&S(A)	5.5-6	NE
23-30 Aug 2013	G&S(A)	--	--
30 Aug-06 Sep 2013	G&S(A)	--	--
06-13 Sep 2013	G&S(A)	--	--
13-24 Sep 2013	G&S(A)	--	--
01 Oct 2013	Ash	--	ESE
15-22 October 2013	Ash	2-10	Various
30 Oct-5 Nov 2013	G&S(A)	--	--
06 Nov 2013	G&S	--	280 km SE
14 Nov 2013	G&S	--	120 km NE

Table 15. KVERT Aviation Color Code levels. Courtesy of KVERT.

Aviation Color Code	Definition
Red	Eruption is forecast to be imminent with significant emission of ash into the atmosphere likely OR Eruption is underway with significant emission of ash into the atmosphere.
Orange	Volcano is exhibiting heightened unrest with increased likelihood of eruption OR Volcanic eruption is underway with no or minor ash emission.
Yellow	Volcano is experiencing signs of elevated unrest above known background levels OR, after a change from higher level, Volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.
Green	Volcano is in normal, non-eruptive state OR, after a change from a higher level, Volcanic activity considered to have ceased, and volcano reverted to its normal, non-eruptive state.

A video of the Kliuchevskoi eruption during October 2013 taken by photographer Martin Rietze and uploaded by Gregg Morgan can be observed at http://www.telegraph.co.uk/news/worldnews/europe/russia/10415179/Eruption-of-Russias-Kliuchevskoi-volcano-filmed-in-timelapse.html.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far East Division, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/); Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Yelizovo Airport (UHPP),(URL: http://www.airport-pkc.ru/); Associated Press (URL: http://www.ap.org/); Itar-Tass (URL: http://tass.ru/); Kamchatka Travel (URL: http://www.travelkamchatka.com /); and NASA Earth Observatory, EOS Project Science Office, NASA Goddard Space Flight Center, Goddard, Maryland, USA (URL: http://earthobservatory.nasa.gov/).

October 2014 (BGVN 39:10) Cite this Report

Two eruptive pulses: 15 August-20 December 2013 and 1 January-24 March 2015

During mid-2013 to early 2015, Klyuchevskoy had two strong eruptive pulses with an intervening lull. The first pulse occurred 15 August-20 December 2013 (~3 months of eruption). Ash plumes and related eruptive activity halted during 2014 until about January 2015 (12 months pause). The second pulse occurred very late December 2014 or very early January 2015 through at least 24 March 2015 (~3 months of eruption).

We start by discussing the latter portion of the first pulse, covering the interval 15 November to 20 December 2013. That time period was missing from our earlier reporting, which ended with our last report (BGVN 38:07) summarizing eruptions during October 2012 through 14 November 2013.

In a later subsection labeled "2015," we discuss the second of the two eruptive pulses. The Global Volcanism Program requires an eruptive repose of three or more months before an eruption is considered to be over; thus, at the time of this writing (6 April 2015), it is too early to tell whether 24 March will hold true as the end date for the later pulse.

We base this report on the reporting interval from the Kamchatkan Volcanic Eruption Response Team (KVERT). Table 15 in BGVN 38:07 delineates the Aviation Color Code (a four-step code from a low of Green, advancing from Yellow to Orange, and ultimately to a high of Red). Klyuchevskoy is also spelled alternatively Kliuchevskoi, Klyuchevskaya Sopka, and Klyuchevskaya.

Late 2013 activity (and lull during 2014). KVERT documented that eruptions were common during 15 August 2013-20 December 2013 (continuing for about 5 weeks beyond our last Bulletin report). Figure 16 shows a photo taken on 16 November 2013 (UTC) by an astronaut aboard the International Space Station. This low angle image highlights some interesting plume dynamics–whereby the dark material at left branches off from a lighter colored plume trending farther to the right (heading ESE)). A NASA Earth Observatory article (posted in 2 December 2013) commented: "The plume—likely a combination of steam, volcanic gases, and ash—stretched to the [ESE] due to prevailing winds. The dark region to the [NNW] is likely a product of shadows and of ash settling out. Several other volcanoes are visible in the image, including Ushkovsky, Tolbachik, Zimina, and Udina. To the [SSW] of Klyuchevskoy lies Bezymianny Volcano, which appears to be emitting a small steam plume (at image center)."

Figure 16. A NE-looking photo taken from space at an oblique angle accentuating topography and showing the Klyuchevskoy eruption of 16 November 2013 (UTC). The image was taken when the ISS was located over a spot on Earth more than 1,500 km to the SW. The scene also labels additional volcanoes in the region (see text). Note N arrow at bottom left. This image and associated labels and interpretation came from the NASA Earth Observatory website (Photo identifier: ISS038-E-5515). Photo credits: Expedition 38 crew; with additional credit to the ISS National Lab and to original captioning information by William L. Stefanov, Jacobs Technology/ESCG, NASA Johnson Space Center, Houston, Texas.

During the reporting interval, KVERT issued multiple reports of a type called a VONA (Volcano Observatory Notices for Aviation), and they provide a record of eruptive activity at Klyuchevskoy. A VONA issued at 0242 on 17 November 2013 indicated that web camera assessments revealed strombolian eruptions with strong gas and steam; an ash plume rose to 7 km altitude and blew 160 km E. The four-step Aviation Color Code (low to high, Green, Yellow, Orange, and Red) rose to Orange. The VONA issued the next day at 0246 on the 18th (UTC) indicated significant decrease in eruptive activity, including a lack of ash plume during the last several hours, but with cautions that aerosols with ash were still possible at low altitudes.

Two VONAs were issued on 19 November 2013; the first at 0248 (UTC) raised the Aviation Color Code from Yellow to Red. This VONA noted that based on seismic data strong ash explosions had resumed at 0216 UTC on the 19th. Visual data showed ash plumes up to 10-12 km altitude extending unstated distances SE.

The VONA for 2341 on the 19th reported a lowered Color Code, to Orange, in response to lowered ash plumes (at 5-5.5 km altitude) during the previous several hours. The plumes blew unstated distances N and NE.

2014. The VONAs for December 2013 and into early January 2014 mentioned some still robust plumes, but the eruption ended on 20 December. A 3 December 2013 VONA indicated that an explosive eruption had seemingly stopped on 19 November, but this was ruled out by a 6 December VONA that again raised the Color Code to Red associated with strong ash plumes up to 5.5-6.0 km altitude and extending over 212 km NE of the volcano.

More information about the 3 December 2013 eruption came out in the 12 December WIR (emphasis added and plume length converted to kilometers): "Seismicity of the volcano increased on December 06, and began to decrease on December 10. Video data showed ash plumes rose up to [5-6 km altitude] on December 06-10. Satellite data showed a very weak thermal anomaly over the volcano summit; ash plumes extended about [1020 km in] the different directions [from] the volcano: to the [E] on December 06-08, to the [NW] on December 09-10, and to the [E and SE] on December 10-11 [2013]." This 1020 km long ash plume was among the longest documented during the reporting interval.

On 7 December a VONA announced the Color Code had dropped to Orange although explosive eruption continued. Video and satellite data revealed a 5.5-km-altitude, NE-directed plume of unstated length. Also, volcanic tremor remained at the previous level (0.7-1.0 mcm/s) and shallow volcanic earthquakes registered.

VONAs issued on 26 December 2013 and 2 January 2014 stated the eruption had ended. The later report noted the eruption end date of 20 December 2014.

No further VONAs were issued for Klyuchevskoy during the remainder of 2014.

2015. Late in 2014, KVERT reported that both the abundance and the magnitude of shallow volcanic earthquakes began to increase during 19-20 December 2014 and again on 31 December 2014; tremor became constant. The volcano was cloaked in clouds during 31 December 2014 to 1 January 2015, but KVERT judged that a strombolian eruption probably began on 1 January 2015, which is consistent with a satellite thermal anomaly. On 2 January 2015, the Aviation Color Code rose from Green (normal) to Yellow (which is a sign of elevated unrest). During the course of January 2015 the volcano resumed frequent eruptive activity and that month KVERT issued ~15 VONAs for Klyuchevskoy. The eruption stopped on 24 March 2015 and any later events after 6 April 2015 extend beyond the current reporting period.

Besides the VONAs, KVERT also creates Weekly Information Releases (hereafter WIRs). The WIR issued on 8 January 2015 stated that both strombolian explosive eruptions of the volcano and associated incandescence continued. Lava bombs rose up to 200-300 m above the crater and ash plumes to ~5 km altitude. Seismic activity of the volcano continued to increase. The magnitude of tremor increased from 3 to 13 x10-5 m/sec. (Note that KVERT reported tremor in units reflecting the velocity of the seismic sensor. They state these units as "mcm/s," 'milli-centimeters per second', which are equivalent to 10-5 m/sec, the means of expression used in this report.) Video data on the 4th and 7th revealed strong gas-steam emissions. Clouds obscured the volcano during other days of the week. Satellite infrared data showed a bright thermal anomaly over the volcano all week.

KVERT's 16 January WIR noted clear visibility of the summit area where bombs were ejected 200-300 m above the summit crater. Strombolian and vulcanian eruptions produced a series of ash plumes that rose to 5-8 km altitude (table 16). The Aviation Color Code increased to Orange.

Figure 17 shows a strombolian eruption at the summit on 19 January 2015. The KVERT caption reported that at this time two centers of strombolian activity and lava flows could be observed at the summit crater. About a week before, video images suggested a new lava flow had started to discharge downslope, and by mid-January through March, lava flows were regularly indicated in KVERT reports (two were seen on the NW slope on 15 March).

The lava flows led to phreatic explosions at the lava flow front. These produced gas-and-steam clouds with minor amounts of ash that during 27-28 January rose to an altitude of 7-8 km. Ashfall was reported in nearby (table 16). Consistent with the lava flows and the spatter from strombolian eruptions, satellite images consistently showed thermal anomalies over the volcano.

Figure 17. Photo of Klyuchevskoy taken during strombolian emissions on 19 Jan 2015. Strombolian activity with bombs rose to heights of 200-300 m and were common around this time (see table 16). Courtesy of Yu. Demyanchuk, IVS FEB RAS, KVERT.

On 15 February, a series of explosions generated ash plumes that rose to an altitude of 8 km, prompting KVERT to raise briefly the Aviation Color Code to Red. Later that day, it was lowered to Orange. During the second half of February, bombs were ejected 150 m above the crater, rather than up to ~300 m, as earlier. Towards the end of February they were no longer reported although that may have been due to lack of visibility or the spatter and bombs may have decreased in size to the point where such emissions became difficult to observe.

On 9 March, the magnitude of seismic tremor significantly decreased. Only moderate emissions of steam and gas were observed, and a thermal anomaly over the summit disappeared. The Aviation Color Code was lowered to Yellow. On 10 March, seismic tremor significantly increased again, prompting KVERT to raise the Aviation Color Code to Orange. Video images showed moderate gas-and-steam activity, while satellite images detected a gas-and-steam plume with small amounts of ash. During 10-17 March, a weak thermal anomaly was detected occasionally over the summit. The eruption continued through the middle of March, but the energy of the explosions decreased significantly, prompting KVERT to lower the Aviation Color Code to Yellow on 25 March.

As of 2 April 2015, KVERT reported that moderate activity continued, with strong fumarole activity. As previously mentioned, KVERT described the explosive eruption as ended on 24 March (table 16).

Table 16. Plume characteristics at Klyuchevskoy during 10 January to 2 April 2015 (UTC). -- means not reported, Bhgt stands for the height above the crater to which bombs were thrown (in meters). Data do not include low-rising emissions. KVERTs satellite-based assessment of the ash content in plumes was generally determined by methods discussed by Ellrod (2012) and Ackerman and others (undated) and references therein. The table was assembled largely from KVERT VONAs and their Weekly Information Releases (WIRs).

Time period	Max. plume altitude (km)	Drift length and direction	Remarks
01 Jan-11 Jan 2015	--	--	(2nd) VONA this day (the only one until the 11th) reported strong and moderate gas-steam plumes during past weeks. Weak thermal anomaly at both the summit and at a SW-flank. Seismically active. WIR issued on 2nd noted that explosive eruption probably continued, and a thermal anomaly appeared on the 1st. Weather clouds often masked visibility. WIR issued the 11th noted strong gas-and-steam emissions and strombolian eruptions. Bhgt 200-300 m. Thermal anomaly, but absence of ash plumes during past week. Clouds often blocked views. Aviation Color Code (2nd and 11th): Yellow
12 Jan-15 Jan 2015	5-7 (11-15th)	In general, 160 km SW and NE	On 11th, ~35 km @ 5 km alt. SSE WIR issued 16 Jan noted the following: Moderate explosive activity. Ashfall in Kozyrevsk village. Bhgt 200-300 m. Thermal anomalies all week. Intervals of increased seismicity and tremor. Aviation Color Code: mainly Orange through 20 March (10-12th) Strong explosive events; ash clouds rose up to 6-10 km alt., strong ashfall on 12th at Klyuchi village (~50 km W of volcano). (10-12th; 15-16th) Ash plumes drifted over 200 km W and SW of volcano.
16 Jan-22 Jan 2015	5-7	210 km SW, NW, NE	WIR issued 23 Jan noted the following: Moderate explosive activity. Bhgt: 200-300 m. Satellite IR thermal anomaly was consistent with hot lava. E flank lava flow noted. (21st) Ashfall in Klyuchi village.
23 Jan-29 Jan 2015	5.5-7 & more (at right)	300 km various (W, N, NE, E, and SE)	WIR issued 30 Jan noted the following. Moderate explosive activity. Good summit visibility; incandescence and thermal anomaly all week. Bhgt: 200-300 m. E flank lava flow. (27-28th) Phreatic explosions at the advancing E-flank lava front produced gas-and-steam plumes with minor amounts of ash that rose to 7-8 km. Ashfall on 27th both in Klyuchi village and near the Khapitsa river, and on 28th in Kozyrevsk village.
30 Jan-04 Feb 2015	5-6 Various during week.	(4-5th) 1,000 km NW and N	WIR issued 5 Feb noted the following. Moderate explosive activity. Ongoing strombolian and vulcanian eruptions all week; Bhgt 200-300 m; advancing E flank lava flows and consistent thermal anomalies. (5th) Ashfall in Klyuchi village.
05 Feb-12 Feb 2015	5.5-6.5	400 km, mainly NW and N	WIR issued 13 Feb noted the following. Moderate explosive activity. Ongoing strombolian and vulcanian eruptions all week. On 7th, ashfall in Kozyrevsk village and on 11th in Klyuchi village. Bhgt 200-300 m.
13 Feb-20 Feb 2015	5-8	Up to 600 km, mainly E, SE, and S during week	WIR issued 21 Feb noted strombolian and vulcanian eruptions: Bhgt: 150 m. (13-16th) Ashfall in Klyuchi village (temporary elevation of Avaiation Color Code to Red).
21 Feb-27 Feb 2015	5-6	90 km NE	WIR issued 28 Feb noted continuing strombolian and vulcanian eruptions and ash explosions. Bhgt not reported in this or later WIRs.
28 Feb-05 Mar 2015	5-6	400 km, mainly E, SE, and NE during week	WIR issued 6 Mar noted moderate eruption continued and still included strombolian and vulcanian eruptions, ash explosions, and summit glow. Thermal anomalies all week.
06 Mar-11 Mar 2015	5-6 (8th and 10th)	~338 km broadly E	WIR issued 12 Mar noted moderate explosive eruptions continued this week. Thermal anomalies on 7th and 10-11th. (9th) Moderate emissions of steam and gas; (10th) similar to 9th but with minor ash.
12 Mar-20 Mar 2015	5-5.5	90 km, broadly E	WIR issued 20 Mar noted moderate ongoing eruption but significantly weaker than in previous weeks. Thermal anomaly weak. Better visibility during 16-17th, poor on other days. (16-17th) (includes observations to left); poor visibility on other days;.) Aviation Color Code Orange
21 Mar-26 Mar 2015	--	--	WIR issued 27 Mar: End of explosive eruption on 24th. Strong fumaroles persisted. Gas-steam plumes containing small amounts of ash on 22nd-23rd. Weak thermal anomaly all week. Aviation Color Code, Yellow.
27 Mar-06 Apr 2015	--	--	WIR issued on 3 Apr stated that strong fumarolic activity and weak thermal anomalies both continued, but that clouds blocked view except for 30th. VONA was issued on 6th: Both high seismicity and moderate gas-steam emissions continued. Aviation Color Code on 3rd Yellow, changing on 10th to Green.

References: Gary Ellrod, 2012, Remote Sensing of Volcanic Ash, National Weather Association (URL: http://www.nwas.org/committees/rs/volcano/ash.htm).

Ackerman, S., Lettvin, E, Mooney, M, Emerson, N, Lindstrom, S, Whittaker, T., Avila, L, Kohrs, R, and Bellon, B., undated, Satellite applications for geoscience education [online course; Facilitating the use of satellite observations in G6-12 Earth Science Education] University of Wisconsin and University of Washington (URL: https://cimss.ssec.wisc.edu/sage/geology/lesson3/concepts.html).

Information Contacts: Kamchatka Volcanic Eruption Response Team (KVERT), Far East Division, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/); Kamchatka Branch, Geophysical Service, Russian Academy of Sciences (KB GS RAS) (URL: http://www.krsc.ru/english/network.htm); NASA Earth Observatory (URL: http://earthobservatory.NASA.gov/); and William L. Stefanov, Jacobs Technology/ESCG, NASA Johnson Space Center, Houston, Texas.

April 2017 (BGVN 42:04) Cite this Report

Mixed explosive and effusive eruption ongoing from August 2015 through March 2017

Klyuchevskoy has been quite active for many decades, with eruptive periods alternating with less active times (BGVN 35:06, 38:07, and 39:10). Recent eruptions took place during August-December 2013, with another period of activity beginning in January 2015 and continuing at least into March 2015 (BGVN 39:10). MODVOLC thermal alert pixels, based on MODIS satellite data, were frequent starting on 3 January but had stopped after 26 February 2015. Moderate activity continued until 10 May 2015, when the eruption that began in January ended. Eruptive activity was again observed in late August 2015, and fluctuating activity has continued through March 2017. The Kamchatkan Volcanic Eruption Response Team (KVERT) is responsible for monitoring this volcano, and is the primary source of information. Times are in UTC (local time is UTC + 12 hours).

Activity during April-July 2015. KVERT lowered the Aviation Color Code (ACC) to Green, the lowest of four levels, on 6 April 2015, although moderate gas-and-steam activity continued. On 13 April, gas-and-steam emissions increased at 0840, and continued at least through 1215 on 14 April, with incandescence at the summit possibly indicative of renewed Strombolian activity. KVERT raised the ACC from Green to Yellow. Strong gas-and-steam activity continued through the rest of April; the plumes sometimes contained small amounts of ash. Satellite data showed a weak thermal anomaly when not obscured by clouds, and incandescence at the summit was occasionally observed. On 18 April, KVERT reported that Strombolian activity was continuing, and that a webcam had recorded a narrow ash plume rising 1-2 km and drifting 100 km SE; the ACC was raised to Orange. Satellite images showed a weak thermal anomaly during 16-17 and 23 April; a gas plume containing a small amount of ash drifted 147 km E on 21 April. On 26 April the ACC was lowered to Yellow; KVERT noted that gas-and-steam activity and tremor continued.

Satellite data showed ash-bearing plumes during 2-5 May that drifted more than 450 km SE, and moderate activity continued through 9 May. The ACC was briefly raised to Orange before again being set at Yellow on 12 May. Moderate activity prevailed though the rest of the month. Satellite data showed occasional gas-and-steam plumes, sometimes containing small amounts of ash; weak thermal anomalies were often observed over the volcano when clouds did not obscure viewing.

On 22 May, KVERT described activity as weak. This remained the case through 27 August 2015. Gas-and-steam emissions continued, and satellite data often showed a thermal anomaly when the volcano was not obscured by clouds. Gas-steam plumes drifted 20 km SE on 26-27 May. On 20 July, the ACC was lowered to Green.

Activity during August 2015-March 2016. On 27 August, KVERT reported that a moderate Strombolian explosion had occurred, which continued into 28 August. At 1544 UTC on 27 August, incandescence of the crater was observed. The ACC was raised to Yellow.

Thereafter, through 17 September 2015, KVERT described activity as moderate, with moderate gas-steam activity. Strombolian explosions occurred on 27-28 August and 8-10 September. Satellite data showed occasional weak thermal anomalies when the volcano was not obscured by clouds. On 13-14 September, a diffuse ash plume rose to about 1.5 km and drifted E.

During 24 September-30 November 2015, KVERT described the activity as a "weak explosive eruption." According to video data, moderate gas-and-steam activity continued and a weak thermal anomaly was sometimes observed when the volcano was not obscured by clouds. Occasionally, incandescence of the summit volcanic crater was noted.

KVERT again described activity as moderate during December 2015-March 2016, with strong gas-steam emissions, although the volcano was usually either quiet or obscured by clouds. KVERT reported thermal anomalies each month, ranging from two during December 2015 to 12 during both January and February 2016. Video often recorded incandescence at the summit during the latter part of December.

Activity during April 2016-November 2016. On 3 April 2016, activity increased with Strombolian explosions. Detection of very frequent thermal anomalies by the MODVOLC system began again on 8 April and continued being reported almost daily through 2 November 2016. Thermal data identified by the MIROVA system showed strong anomalies over the same time period (figure 18). The MIROVA data also indicated a steady increase in radiative power beginning in the second half of May 2016.

Figure 18. Plots of MODIS thermal data detected at Klyuchevskoy during the year ending on 23 March 2017. The data analyzed by the MIROVA system is presented as radiative power (top) and log radiative power (bottom). Courtesy of MIROVA.

Strong gas-steam emissions continued, and plumes extended to about 100 km SE on 10 April and about 55 km NE on 14-15 April. Satellite data by KVERT through June showed persistent intense thermal anomalies when not obscured by clouds. On 24 April, activity increased again. According to video and satellite data, a lava flow began to effuse on the S and SE flank of the volcano (along Apakhonchich chute). An ash plume drifted about 500 km SW on 23-24 April. The ACC was raised to Orange.

The explosive-effusive eruption continued from May through September 2016. Lava continued to effuse along the SE flank. Satellite data showed an ash plume extending 88 km SE on 2 May, up to 80 km E and SE on 13 May and 16 May, 47 km W on 13 June, about 30 km E on 18 June, and 60 km W and E on 27-28 June. Gas-steam plumes drifted about 60 km W and E on 27 and 28 June. On 24 June, at 2115 and 2350 UTC, video data showed two rock collapses into the Apakhonchich chute and ash plumes drifted W, then NW. According to video and satellite data, Strombolian activity of the summit crater continued on 24 June.

According to video data, the eruption intensified on 6 July. Strong explosions sent ash to an altitude of 7.5 km and the plumes drifted about 350 km SW, S, and SE. A large bright thermal anomaly was observed all that week. On 6-7 July, dense ash plumes drifted about 400 km SE and E, and numerous ash plumes were observed thereafter through September. Bursts of volcanic bombs shot up to 200-300 m above the summit crater and up to 50 m above the cinder cone into the Apakhonchich chute along the SE flank. Lava continued to flow on the SE flank along the chute (figure 19). Strong gas-steam activity within two volcanic centers emitted various amounts of ash. On 10, 13 and 15 September, explosions shot ash up to an altitude of 7 km and ash plumes extended for about 50 km SE and NE.

Figure 19. Photo of Klyuchevskoy on 25 August 2016 with ash-containing emissions and lava streaming from the cone into the Apakhonchich chute. Courtesy of Denis Bud'kov/Bernard Duick.

During the second week of September, KVERT reported that lava began to effuse on the E and SW flanks. Explosions sent ash up to an altitude of 7.5 km and ash plumes extended for about 530 km in various directions. Small ash layers were observed over Koryaksky and Avachinsky volcanoes on 8 September. On 10, 13, 15, and 20-22 September, explosions sent ash up to an altitude of 6-7 km and ash plumes extended for up to 165 km in various directions. In their 29 September and 6 October reports, KVERT noted that bursts of volcanic ash that rose above the summit crater and cinder cone fell into Apakhonchich chute.

Explosions during the first week of October sent ash to an altitude of 5-6 km and plumes extended about 260 km E. On 7-8 October, gas-steam plumes containing ash drifted about 390 km E and SE. By 13 October, activity had apparently diminished, with moderate gas-steam emissions containing some ash. A weak thermal anomaly was noted on 7 and 12 October.

By 20 October the explosive-effusive activity had returned with a lava flow on the E flank, a large strong thermal anomaly, and strong gas-steam emissions containing various amounts of ash. Explosions sent ash to 5-6 km altitude and plumes extended for about 300 km E, SE, and NW on 14 and 18-19 October. On 20-21 and 23-27 October explosions sent ash up to an altitude of 5-7 km; gas-steam plumes containing ash extended for about 335 km in various directions. On 30-31 October and 1-3 November, explosions sent ash up to an altitude of 5-8 km and gas-steam plumes containing ash extended for about 277 km E and SE. Strong thermal anomalies detected from satellite by the MODIS instrument decreased significantly in strength after 2 November.

On 3-5 November, ash plumes extended up to 116 km E. KVERT's report on 10 November noted that activity had decreased significantly during the previous week. Lava effusion onto the flanks was last noted on 3 November; the next day the thermal anomaly was weaker. Ash plumes were last detected in satellite images during 3-4 November. The ACC was lowered to Yellow on 7 November. However, moderate activity continued and thermal anomalies and Strombolian activity could still be observed. Strong gas-and-steam emissions continued. On 16 November, an ash plume extended up to 85 km NW. KVERT reported a daily thermal anomaly visible in satellite images during 18-25 November.

Activity during December 2016-March 2017. Thermal anomaly data after early November 2016 was not sufficient to cause alerts on MODVOLC, and was seen to be very weak and fluctuating in MIROVA plots before ending completely in mid-February 2017 (see figure 19). On 26 December KVERT reported that a weak thermal anomaly had been detected and that gas-and-steam plumes sometimes contained small amounts of ash. Over the next few months the ACC was frequently changed between Yellwo and Orange, depending on the ash plume hazard to aviation.

Explosions on 1 January 2017 generated ash plumes that rose to an altitude of 5 km and drifted 114 km SE, resulting in KVERT raising the ACC to Orange. Daily satellite imagery showed a thermal anomaly over the volcano during 2-6 January. Gas-and-steam emissions sometimes with minor ash, along with thermal anomalies, continued through 20 January. During 9-10 January ash plumes drifted 160 km ESE, and on 22 January an ash plume rose to 5-5.5 km and drifted 45 km E.

KVERT reported that a thermal anomaly was identified in satellite data during 25 February and 1-3, 5, and 8-9 March. At 1340 on 2 March a gas, steam, and ash plume recorded by the webcam rose to altitudes of 8-9 km and drifted 110 km NE and NW. Explosions on 8 March produced ash plumes that rose to 5.5 km altitude and drifted about 20 km NW. As of 24 March gas-and-steam emissions continued to rise from the crater, and a weak thermal anomaly was sometimes identified in satellite images, but no explosions had been detected since 8 March. On 24 March the ACC was lowered to Green.

A gas, steam, and ash plume identified in satellite data on 28 March rose to altitudes of 5-6 km and drifted 108 km ENE, resulting in the ACC being raised to Yellow. Another ash plume the next day that rose to as high as 7.5 km altitude and drifted 75 km SW prompted an Orange ACC status. Additional explosions during 27-30 March generated ash plumes to an altitude of 7 km that drifted 300 km in multiple directions.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far East Division, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/); Hawai'i Institute of Geophysics and Planetology (HIGP), MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/).

November 2017 (BGVN 42:11) Cite this Report

Eruption appears to have subsided after March 2017; ash plumes persist into October

The eruption of Klyuchevskoy that began in late August 2015 continued with fluctuating activity through March 2017 (BGVN 42:04) (figure 20). Although lava effusion ended in early November 2016, explosive activity was observed through March 2017 (BGVN 42:04). Similar eruptive activity continued through October 2017 as reported here, exhibiting moderate to strong ash explosions. The Kamchatkan Volcanic Eruption Response Team (KVERT) is responsible for monitoring this volcano, and is the primary source of information. Times are in UTC (local time is UTC + 12 hours).

Figure 20. Ash plume rising from the summit crater of Klyuchevskoy on 30 March 2017. Courtesy of Yu. Demyanchuk (IVS FEB RAS, KVERT).

KVERT reported that weak to moderate ash explosions and thermal anomalies occurred throughout March-October 2017 (table 17). The last time ash was reported during the period of this report was on 7 September 2017. The volcano is often obscured by clouds that prevent plumes from being detected in satellite imagery. However, excellent clear views from space were obtained on 10 June (figure 21) and 17 August 2017 (figures 22 and 23) that showed typical ash plumes. Ground-based observers also noted erupting ash plumes, some not identified in satellite imagery, including one on 8 October 2017 (figure 24).

Table 17. Summary of ash plumes and Aviation Color Codes at Klyuchevskoi from March through mid-October 2017. Data courtesy of KVERT.

Dates	Ash plume altitude	Ash plume drift	Aviation Color Code (ACC)
02 Mar 2017	8-9 km	110 km NW and NE	Raised to Orange
08 Mar 2017	5.5 km	20 km NW	Orange
16 Mar 2017	--	--	Lowered to Yellow
24 Mar 2017	--	--	Lowered to Green
28 Mar 2017	5-6 km	108 km ENE	Raised to Yellow
29 Mar 2017	7.5 km	75 km SW	Raised to Orange
01-04 Apr 2017	5-6 km	400 km various directions	Lowered to Yellow
21-28 Apr 2017	--	125 km SW	Orange
5-6, 10-11 May 2017	--	270 km SE and NW	Orange
17 May 2017	6 km	180 km N and NE	Orange
01-02 Jun 2017	6 km	400 km SSE	Orange
02-09 Jun 2017	5 km	325 km NE, SE, and SW	Orange
09-16 Jun 2017	6-7 km	580 km SW and SE	Orange
16-17, 22 Jun 2017	6-7 km	300 km E and W	Orange
24, 26 Jun 2017	5-6 km	112 km S and SE	Orange
01-03, 05-06 Jul 2017	5 km	160 km SE, E, and SW	Orange
08, 12-13 Jul 2017	5 km	50 km SE	Orange
19-20 Jul 2017	--	300 km SW, SE, E, and NE	Orange
22-27 Jul 2017	--	120 km E and NE	Orange
02-03 Aug 2017	--	65 km SW and 250 km ESE	Orange
11-12, 15-17 Aug 2017	--	315 km E and NW	Orange
19 Aug 2017	6 km	140 km NW, 270 km SE, 90 km NE	Orange
20 Aug 2017	--	200 km NW	Orange
21 Aug 2017	--	480 km NW	Orange
22 Aug 2017	--	110 km NW, W, and SW	Orange
23 Aug 2017	--	220 km NW	Orange
24-25, 30 Aug 2017	6 km	550 km various directions	Lowered to Yellow
07 Sep 2017	6 km	50 km NE	Orange

Figure 21. A brown ash plume can be seen rising from Klyuchevskoy on 10 June 2017 in this image taken from space looking NE. The tall peak adjacent to Klyuchevskoy and to the S is Kamen; adjacent and just S of that is Bezymianny. The snow-covered mass to the NW contains Ushkovsky volcano. South of the Klyuchevskoy-Kamen pair is the snow-covered active volcano Tolbachik, east of which are the snow-free Zimina (to the north) and Udina volcanos. Courtesy of NASA Johnson Space Center (photo ISS052-E-896).

Figure 22. The Operational Land Imager (OLI) on Landsat 8 satellite captured this image of a volcanic ash plume streaming W from Klyuchevskoy on 19 August 2017. The plume is brown; clouds are white. Note that there is also a smaller white plume extending SW from Bezymianny, about 10 km S. An enlarged image of the "Detail" area is shown in the next figure. Courtesy of NASA Earth Observatory; image by J. Stevens, using Landsat data from the U.S. Geological Survey.

Figure 23. Detail from an Operational Land Imager (OLI) on Landsat 8 image of Klyuchevskoy erupting on 19 August 2017. The ash plume is rising about 6 km above the summit. Courtesy of NASA Earth Observatory; image by J. Stevens, using Landsat data from the U.S. Geological Survey.

Figure 24. Ash plume rising from the summit crater of Klyuchevskoy on 8 October 2017. Courtesy of I. Borisov (IVS FEB RAS).

Thermal alerts in the MODVOLC system ended on 2 November 2016, corresponding to the end of lava effusion reported by KVERT (BGVN 42:04). The number of MIROVA thermal anomalies decreased significantly in early November 2016 as well (figure 25), then gradually declined further over the next few months.

Figure 25. MODIS thermal anomalies identified in the MIROVA system, plotted as log radiative power for the year ending 24 October 2017. Courtesy of MIROVA.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Institute of Volcanology and Seismology, Far Eastern Branch, Russian Academy of Sciences (IVS FEB RAS), 9 Piip Blvd., Petropavlovsk-Kamchatsky 683006, Russia (URL: http://www.kscnet.ru/ivs/eng/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); NASA Earth Observatory, EOS Project Science Office, NASA Goddard Space Flight Center, Goddard, Maryland, USA (URL: http://earthobservatory.nasa.gov/).

May 2018 (BGVN 43:05) Cite this Report

Intermittent moderate gas, steam, and ash plumes during December 2017-February 2018

Klyuchevskoy has been active for many decades, alternating between eruptive and less active periods. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters. The current eruptive period began in late August 2015. Lava effusion ended in early November 2016 but explosive activity continued to be observed through October 2017 (BGVN 42:11) and into mid-February 2018 as described below. The Kamchatkan Volcanic Eruption Response Team (KVERT) is responsible for monitoring, and is the primary source of information. The Aviation Color Code remained at Orange through April 2018.

Strong gas-and-steam activity was observed on 2-5 December 2017. Ash plumes rose to an altitude of 5.5 km and extended for about 180 km (figure 26). Emissions were reported at 2300 on 5 December 2017 with plumes extending 170 km E. Gas-and-steam and ash plumes extended for approximately 95 km to the E and SW on 7 and 13 December, respectively. On 16-19 December the gas-steam and ash plumes extended approximately 140 km E, and on 22-25 December they reached about 220 km E.

Figure 26. Photo of Klyuchevskoy showing a gas-and-steam plume on 3 December 2017. Courtesy of Yu. Demyanchuk (IVS FEB RAS, KVERT).

Moderate eruptive activity continued into January and February 2018. On 1, 3, and 4 January gas-and-steam plumes with ash extended approximately 150 km downwind. The plume extended to 160 km N, W, and E on 5, 6, and 8-10 January (figures 27 and 28). On 12 and 17-18 January, the plume extended to 120 km W and E. The Tokyo VAAC reported that on 18 February an ash plume rose to an altitude of 5.2 km and extended SW. No further reports of ash plumes were reported through April 2018.

Figure 27. Gas-and-steam plume with minor ash content rising from Klyuchevskoy on 6 January 2018. Courtesy of Yu. Demyanchuk (IVS FEB RAS, KVERT).

Figure 28. Close-up satellite image of a small plume of gas, steam, and ash rising from Klyuchevskoy on 10 January 2018 taken by the Operational Land Imager (OLI) on Landsat 8. Courtesy of NASA Earth Observatory, with imagery by Joshua Stevens and Jeff Schmaltz, using Landsat data from the U.S. Geological Survey.

A weak thermal anomaly was detected over the volcano on 5, 6, 11, 16, and 22, December 2017; and on 3, 6, 8, 11, 12, 15 and 17 January 2018. The number of MIROVA thermal anomalies detected also increased in the first half of January 2018; most were low to slightly moderate in intensity.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Institute of Volcanology and Seismology, Far Eastern Branch, Russian Academy of Sciences (IVS FEB RAS), 9 Piip Blvd., Petropavlovsk-Kamchatsky 683006, Russia (URL: http://www.kscnet.ru/ivs/eng/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); NASA Earth Observatory, EOS Project Science Office, NASA Goddard Space Flight Center, Goddard, Maryland, USA (URL: http://earthobservatory.nasa.gov/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/).

August 2018 (BGVN 43:08) Cite this Report

Intermittent moderate gas, steam, and ash emissions; no ash seen after 15 June 2018

The current eruptive period at Klyuchevskoy began in late August 2015 (BGVN 39:10). Lava effusion ended in early November 2016 (BGVN 42:04), but explosive activity continued to be observed through February 2018 (BGVN 43:05). From mid-February through mid-August 2018 moderate to weak gas and steam plumes were observed (figure 29), but no ash plumes were reported after 15 June 2018 (figure 29). The Kamchatkan Volcanic Eruption Response Team (KVERT) is responsible for monitoring, and is the primary source of information. The Aviation Color Code was lowered from Orange to Yellow during this reporting period.

Figure 29. Fumarolic plume rising from the summit of Klyuchevskoy, 15 April 2018. Courtesy of Yu. Demyanchuk (IVS FEB RAS, KVERT).

The Aviation Color Code (ACC) was lowered to Yellow by KVERT on 9 February. On 18 February an ash plume that rose to 5.2 km in altitude was reported by the Tokyo Volcanic Ash Advisory Center (VAAC). Moderate gas and steam activity was reported on 25 and 29 April, and 2 May 2018. During 7-8 and 10 May KVERT reported that gas, steam, and ash plumes rose to 5.0-5.5 km altitude and extended to 340 km SE; subsequently the ACC was raised back to Orange. Explosions were reported on 14 May with accompanying ash plumes that rose to 10.5 km in altitude. The ash clouds lingered around Klyuchevskoy and surrounding volcanoes for about eight hours before gradually dissipating. Nighttime summit incandescence and a hot avalanche was observed. A diffuse ash plume was reported by KVERT on 6 June that extended 12 km to the W. Another ash plume was visible on 15 June, but decreasing activity resulted in the ACC being lowered to Yellow again on 29 June. Only moderate gas and steam activity was noted through mid-August.

A thermal anomaly was reported over Klyuchevskoy approximately 16 times during this reporting period in February, April, May, June, and August 2018. The number of MIROVA thermal anomalies detected increased in the first half of January 2018, with decreasing and intermittent low-intensity detections in subsequent months (figure 30).

Figure 30. MODIS thermal anomalies identified in the MIROVA system, plotted as log radiative power for the year ending 24 August 2018. Courtesy of MIROVA.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/).

July 2019 (BGVN 44:07) Cite this Report

Weak thermal anomalies and moderate Strombolian-type eruptions in September 2018-June 2019

Klyuchevskoy has had alternating eruptive and less active periods since August 2015. Activity has included lava flows, a growing cinder cone, thermal anomalies, gas-and-steam plumes, and ash explosions. Though some eruptions occur near the summit crater, major explosive and effusive eruptions have also occurred from flank craters (BGVN 42:04 and 43:05). Intermittent moderate gas-and-steam and ash emissions were previously reported from mid-February to mid-August 2018. The Kamchatka Volcanic Eruptions Response Team (KVERT) is the primary source of information for this September 2018-June 2019 reporting period.

KVERT reported that moderate gas-and-steam activity and weak thermal anomalies occurred intermittently from the beginning of September 2018 through mid-April 2019. [On 9 April a small ash plume was observed, according to KVERT. The Tokyo VAAC reported an ash plume on 12 April that rose 5.2 km altitude and extended NE.] On 21-22 April webcam data showed a gas-and-steam plume extending about 160 km SE (figure 31). Moderate Strombolian-type volcanism began late April 2019 and continued intermittently through June 2019. On 11-12 June webcam data showed explosions that sent ash up to a maximum altitude of 6 km, with the resulting ash plume extending about 200 km WNW.

Figure 31. Gas-and-steam plume containing some amount of ash rising from the summit of Klyuchevskoy on 22 April 2019. Photo by A. Klimova, courtesy of Institute of Volcanology and Seismology (IVS FEB RAS).

Thermal anomalies were noted by KVERT during two days in September 2018, six days in April 2019, eleven days in May 2019, and six days in June 2019. MIROVA (Middle InfraRed Observation of Volcanic Activity) analysis of MODIS satellite data showed infrequent weak thermal anomalies December 2018 through early May 2019.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/).

October 2019 (BGVN 44:10) Cite this Report

Ongoing weak thermal anomalies during July-September 2019, but no ash plumes after 1 August

During September 2018 through June 2019, activity at Klyuchevskoy was characterized by weak thermal anomalies and moderate Strombolian-type explosions. Ash emissions were only reported on 1-2 July and 1 August during the period of July-September 2019. The volcano is monitored by the Kamchatkan Volcanic Eruption Response Team (KVERT) and is the primary source of information.

According to KVERT, moderate activity continued from July through at least the middle of September, with gas-and-steam emissions. At the beginning of July, KVERT reported incandescence in the crater. During 1-2 July, ash plumes drifted as far as 85 km E and SE. Ash plumes were visible blowing E in Sentinel-2 images on 17 and 19 July (figure 32); steam plumes were evident on some other days. KVERT reported that an ash emission was seen in webcam images on 1 August.

Figure 32. An ash plume can be seen blowing E from the summit crater of Klyuchevskoy in this Sentinel-2 natural color (bands 4, 3, 2) satellite image from 17 July 2019. Courtesy of Sentinel Hub Playground.

No thermal anomalies were detected with the MODIS satellite instruments analyzed using the MODVOLC algorithm. The MIROVA (Middle InfraRed Observation of Volcanic Activity) volcano hotspot detection system, also based on analysis of MODIS data, detected no thermal anomalies in June, four scattered ones in July, and only one in August, all low power. According to KVERT, a weak thermal anomaly was detected throughout the reporting period, at least through mid-September, except for the numerous days when the volcano was obscured by clouds; the temperature of the anomalies had steadily decreased with time.

Instruments aboard NASA satellites detected high levels of sulfur dioxide near or directly above the volcano every day during the first week of July and on 12 July, but not on other days during the reporting period. However, the origin for the high levels may, at least in part, have been due to other active volcanoes in the area.

At the beginning of July, the Aviation Color Code (ACC) remained at Orange (the second highest level on a four-color scale). Because of decreased activity, KVERT lowered the ACC to Yellow on 30 August and to Green (the lowest on the scale) on 24 September.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Global Sulfur Dioxide Monitoring Page, Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center (NASA/GSFC), 8800 Greenbelt Road, Goddard, Maryland, USA (URL: https://so2.gsfc.nasa.gov/).

June 2020 (BGVN 45:06) Cite this Report

Strombolian activity November 2019 through May 2020; lava flow down the SE flank in April

Klyuchevskoy is part of the Klyuchevskaya volcanic group in northern Kamchatka and is one of the most frequently active volcanoes of the region. Eruptions produce lava flows, ashfall, and lahars originating from summit and flank activity. This report summarizes activity during October 2019 through May 2020, and is based on reports by the Kamchatkan Volcanic Eruption Response Team (KVERT) and satellite data.

There were no activity reports from 1 to 22 October, but gas emissions were visible in satellite images. At 1020 on 24 October (2220 on 23 October UTC) KVERT noted that there was a small ash component in the ash plume from erosion of the conduit, with the plume reaching 130 km ENE. The Aviation Colour Code was raised from Green to Yellow, then to Orange the following day. An ash plume continued on the 25th to 5-7 km altitude and extending 15 km SE and 70 km SW and reached 30 km ESE on the 26th. Similar activity continued through to the end of the month.

Moderate gas emissions continued during 1-19 November, but the summit was obscured by clouds. Strong nighttime incandescence was visible at the crater during the 10-11 November and thermal anomalies were detected on 8 and 10-13 November. Explosions produced ash plumes up to 6 km altitude on the 20-21st and Strombolian activity was reported during 20-22 November. Degassing continued from 23 November through 12 December, and a thermal anomaly was visible on the days when the summit was not covered by clouds. An ash plume was reported moving to the NW on the 13th, and degassing with a thermal anomaly and intermittent Strombolian activity then resumed, continuing through to the end of December with an ash plume reported on the 30th.

Gas-and-steam plumes continued into January 2020 with incandescence noted when the summit was clear (figure 33). Strombolian activity was reported again starting on the 3rd. A weak ash plume produced on the 6th extended 55 km E, and on the 21st an ash plume reached 5-5.5 km altitude and extended 190 km NE (figure 34). Another ash plume the next day rose to the same altitude and extended 388 km NE. During 23-29 Strombolian activity continued, and Vulcanian activity produced ash plumes up to 5.5 altitude, extending to 282 km E on the 30th, and 145 km E on the 31st.

Figure 33. Incandescence and degassing were visible at Klyuchevskoy through January 2020, seen here on the 11th. Courtesy of KVERT.

Figure 34. A low ash plume at Klyuchevskoy on 21 January 2020 extended 190 km NE. Courtesy of KVERT.

Strombolian activity continued throughout February with occasional explosions producing ash plumes up to 5.5 km altitude, as well as gas-and-steam plumes and a persistent thermal anomaly with incandescence visible at night. Starting in late February thermal anomalies were detected much more frequently, and with higher energy output compared to the previous year (figure 35). A lava fountain was reported on 1 March with the material falling back into the summit crater. Strombolian activity continued through early March. Lava fountaining was reported again on the 8th with ejecta landing in the crater and down the flanks (figure 36). A strong persistent gas-and-steam plume containing some ash continued along with Strombolian activity through 25 March (figure 37), with Vulcanian activity noted on the 20th and 25th. Strombolian and Vulcanian activity was reported through the end of March.

Figure 35. This MIROVA thermal energy plot for Klyuchevskoy for the year ending 29 April 2020 (log radiative power) shows intermittent thermal anomalies leading up to more sustained energy detected from February through March, then steadily increasing energy through April 2020. Courtesy of MIROVA.

Figure 36. Strombolian explosions at Klyuchevskoy eject incandescent ash and gas, and blocks and bombs onto the upper flanks on 8 and 10 March 2020. Courtesy of IVS FEB RAS, KVERT.

Figure 37. Weak ash emission from the Klyuchevskoy summit crater are dispersed by wind on 19 and 29 March 2020, with ash depositing on the flanks. Courtesy of IVS FEB RAS, KVERT.

Activity was dominantly Strombolian during 1-5 April and included intermittent Vulcanian explosions from the 6th onwards, with ash plumes reaching 6 km altitude. On 18 April a lava flow began moving down the SE flank (figures 38). A report on the 26th reported explosions from lava-water interactions with avalanches from the active lava flow, which continued to move down the SE flank and into the Apakhonchich chute (figures 39 and 40). This continued throughout April and May with sustained Strombolian and intermittent Vulcanian activity at the summit (figures 41 and 42).

Figure 38. Strombolian activity produced ash plumes and a lava flow down the SE flank of Klyuchevskoy on 18 April 2020. Courtesy of IVS FEB RAS, KVERT.

Figure 39. A lava flow descends the SW flank of Klyuchevskoy and a gas plume is dispersed by winds on 21 April 2020. Courtesy of Yu. Demyanchuk, IVS FEB RAS, KVERT.

Figure 40. Sentinel-2 thermal satellite images show the progression of the Klyuchevskoy lava flow from the summit crater down the SE flank from 19-29 April 2020. Associated gas plumes are dispersed in various directions. Courtesy of Sentinel Hub Playground.

Figure 41. Strombolian activity at Klyuchevskoy ejects incandescent ejecta, gas, and ash above the summit on 27 April 2020. Courtesy of D. Bud'kov, IVS FEB RAS, KVERT.

Figure 42. Sentinel-2 thermal satellite images of Klyuchevskoy show the progression of the SE flank lava flow through May 2020, with associated gas plumes being dispersed in multiple directions. Courtesy of Sentinel Hub Playground.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).

September 2020 (BGVN 45:09) Cite this Report

Strombolian activity, gas-and-steam and ash plumes, and a lava flow during June-early July 2020

Klyuchevskoy is a frequently active stratovolcano located in northern Kamchatka. Historical eruptions dating back 3,000 years have included more than 100 flank eruptions with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks. The previous report (BGVN 45:06) described ash plumes, nighttime incandescence, and Strombolian activity. Strombolian activity, ash plumes, and a strong lava flow continued. This report updates activity from June through August 2020 using weekly and daily reports from the Kamchatkan Volcanic Eruption Response Team (KVERT), the Tokyo Volcanic Ash Advisory (VAAC), and satellite data.

Moderate explosive-effusive activity continued in June 2020, with Strombolian explosions, frequent gas-and-steam emissions that contained some amount of ash, and an active lava flow. On 1 June a gas-and-steam plume containing some ash extended up to 465 km SE and E. The lava flow descended the SE flank down the Apakhonchich chute (figure 43). Occasionally, phreatic explosions accompanied the lava flow as it interacted with snow. Intermittent ash plumes, reported throughout the month by KVERT using video and satellite data and the Tokyo VAAC using HIMAWARI-8 imagery, rose to 5.5-6.7 km altitude and drifted in different directions up to 34 km from the volcano. On 12 and 30 June ash plumes rose to a maximum altitude of 6.7 km. On 19 June, 28-30 June, and 1-3 July some collapses were detected alongside the lava flow as it continued to advance down the SE flank.

Figure 43. Gray ash plumes (left) and a lava flow descending the Apakhonchich chute on the SE flank, accompanied by a dark ash plume and Strombolian activity (right) were observed at the summit of Klyuchevskoy on 10 June 2020. Courtesy of E. Saphonova, IVS FEB RAS, KVERT.

During 1-3 July moderate Strombolian activity was observed, accompanied by gas-and-steam emissions containing ash and a continuous lava flow traveling down the Apakhonchich chute on the SE flank. On 1 July a Tokyo VAAC advisory reported an ash plume rising to 6 km altitude and extending SE. On 3 July the activity sharply decreased. KVERT reported there was some residual heat leftover from the lava flow and Strombolian activity that continued to cool through at least 13 July; KVERT also reported frequent gas-and-steam emissions, which contained a small amount of ash through 5 July, rising from the summit crater (figure 44). The weekly KVERT report on 16 July stated that the eruption had ended on 3 July 2020.

Figure 44. Fumarolic activity continued in the summit crater of Klyuchevskoy on 7 July 2020. Courtesy of KSRS ME, Russia, KVERT.

MIROVA (Middle InfraRed Observation of Volcanic Activity) analysis of MODIS satellite data shows frequent and strong thermal activity within 5 km of the summit crater from March through June followed by a sharp and sudden decline in early July (figures 45). A total of six weak thermal anomalies were detected between July and August. According to the MODVOLC thermal algorithm, a total of 111 thermal alerts were detected at or near the summit crater from 1 June to 1 July, a majority of which were due to the active lava flow on the SE flank and Strombolian explosions in the crater. Sentinel-2 thermal satellite imagery frequently showed the active lava flow descending the SE flank as a strong thermal anomaly, sometimes even through weather clouds (figure 46). These thermal anomalies were also recorded by the Sentinel-2 MODIS Thermal Volcanic Activity data on a MIROVA graph, showing a strong cluster during June to early July, followed by a sharp decrease and then a hiatus in activity (figure 47).

Figure 45. Thermal activity at Klyuchevskoy was frequent and strong during February through June 2020, according to the MIROVA graph (Log Radiative Power). Activity sharply decreased during July through August with six low-power thermal anomalies. Courtesy of MIROVA.

Figure 46. Sentinel-2 thermal satellite images show the strong and persistent lava flow (bright yellow-orange) originating from the summit crater at Klyuchevskoy from 1 June through 1 July 2020. The lava flow was active in the Apakhonchich chute on the SE flank. Sentinel-2 satellite images with “Atmospheric penetration” (bands 12, 11, 8A) rendering; courtesy of Sentinel Hub Playground.

Figure 47. Strong clusters of thermal anomalies were detected in the summit at Klyuchevskoy (red dots) during January through June 2020, as recorded by the Sentinel-2 MODIS Thermal Volcanic Activity data (bands 12, 11, 8A). Activity sharply decreased during July through August with few low-power thermal anomalies. Courtesy of MIROVA.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).

January 2021 (BGVN 46:01) Cite this Report

Renewed activity in October 2020 with explosions, lava flows, and ash plumes

Klyuchevskoy, located in northern Kamchatka, has had historical eruptions dating back 3,000 years characterized by major explosive and effusive eruptions from the flank craters. The current eruption began in April 2019 and has recently consisted of Strombolian activity, ash plumes, and an active lava flow descending the SE flank (BGVN 45:09). This report covers September-December 2020 and describes similar activity of Strombolian explosions, ash plumes, and active lava flows beginning in early October. Information primarily comes from weekly and daily reports from the Kamchatkan Volcanic Eruption Response Team (KVERT), the Tokyo Volcanic Ash Advisory (VAAC), and satellite data.

Activity from July through September was relatively low, with no thermal activity detected during August-September. On 2 October renewed Strombolian explosions began at 1003, ejecting ash 300-400 m above the summit and producing gas-and-steam plumes with some ash that drifted down the E flank (figure 48). That night, crater incandescence was visible. On 5 October KVERT reported that a lava flow began to effuse along the Apakhonchich chute at 0100. During 7-8 October activity intensified and was characterized by strong explosions, collapses of the sides of the drainage, strong thermal anomalies, and ash plumes that extended over 200 km SE from the crater; the lava flow remained active and continued to descend the SE flank. A Tokyo VAAC advisory issued on 7 October reported that an ash plume rose to 8.8 km altitude and drifted E and SE; during 8-9 October ash plumes rose to 5.5 km altitude and drifted as far as 270 km SE. A strong, bright, thermal anomaly was observed daily in satellite imagery, which represented the new lava flow. Strombolian explosions continued throughout the month, accompanied by gas-and-steam plumes containing some ash and an active lava flow advancing down the Apakhonchich chute on the SE flank (figure 49).

Figure 48. Photos of a gray ash plume (left) and the beginning of the lava flow (right), represented as summit crater incandescence at Klyuchevskoy on 2 October 2020 at 1030 and 2100, respectively. Photos by Y. Demyanchuk; courtesy of Volkstat.

Figure 49. Photo of Strombolian explosions at the summit of Klyuchevskoy accompanied by ash emissions and a lava flow advancing down the SE-flank Apakhonchich chute on 25 October 2020. Photo by Y. Demyanchuk (color corrected); courtesy of Volkstat.

Similar activity continued to be reported in November, consisting of Strombolian explosions, ash plumes, and a lava flow advancing down the SE flank. A bright thermal anomaly was observed in thermal satellite imagery each day during the month. During 16-19 November explosions recorded in satellite and video data showed ash plumes rising to 7.5 km altitude and drifting as far as 108 km to the NE, E, SE, and S (figure 50). On 19 November an ash cloud 65 x 70 km in size drifted 50 km SE, according to a KVERT VONA (Volcano Observatory Notice for Aviation). During 26-30 November video and satellite data showed that gas-and-steam plumes containing some ash rose to 7 km altitude and extended as far as 300 km NW and E, accompanied by persistent moderate explosive-effusive activity (figure 51).

Figure 50. Photo of the Strombolian and Vulcanian explosions at Klyuchevskoy on 18 November 2020 which produced a dense gray ash plume. Photo by Yu. Demyanchuk, IVS FEB RAS, KVERT

Figure 51. Photo of the summit of Klyuchevskoy (right foreground) showing incandescent Strombolian explosions, the lava flow descending the Apakhonchich chute on the SE flank, and a gray ash plume on 29 November 2020. Kamen volcano is the cone at back left. Photo by Y. Demyanchuk (color corrected); courtesy of Volkstat.

Moderate explosive-effusive activity continued through December; a strong daily thermal anomaly was visible in satellite images. During 2-3 December gas-and-steam plumes containing some ash rose to 7 km altitude and extended 300 km NW and E. Intermittent gas-and-ash plumes continued through the month. On 7 December KVERT reported that a new lava flow began to advance down the Kozyrevsky chute on the S flank, while the flow on the SE flank continued. Strombolian explosions in the crater ejected incandescent material up to 300 m above the crater on 8 December while hot material was deposited and traveled 350 m below the crater. A cinder cone was observed growing in the summit crater and measured 75 m tall.

Strombolian and Vulcanian activity continued during 11-25 December, accompanied by the lava flow on the S flank; according to Sentinel-2 thermal satellite images, the effusion on the SE flank had stopped around 13 December and had begun to cool. The lava flow in the Kozyrevsky chute spalled off incandescent material that continued to travel an additional 350 m. Gas-and-steam plumes that contained some ash rose to 6 km altitude and drifted up to 350 km generally E. On 24 December the Kamchatka Volcanological Station field team visited Klyuchevskoy to do work on the field stations. The scientists observed explosions that ejected incandescent material 300 m above the crater and the S-flank lava flow (figure 52). On 28 December KVERT reported that the moderate explosive-effusive eruption continued, but the intensity of the explosions had significantly decreased. The lava flow on the S flank continued to effuse, but its flow rate had already decreased.

Figure 52. Photos of a dense ash plume (left) and a color corrected photo of the lava flow advancing on the S flank (right) of Klyuchevskoy on 24 December 2020, accompanied by incandescent Strombolian explosions and a gray ash plume. Photos by Y. Demyanchuk; courtesy of Volkstat.

MIROVA (Middle InfraRed Observation of Volcanic Activity) analysis of MODIS satellite data shows frequent and strong thermal activity beginning in early October and continuing through December 2020, which is represented by the active lava flows reported in the summit crater (figure 53). According to the MODVOLC thermal algorithm, a total of 615 thermal alerts were detected at or near the summit crater from 1 October to 31 December; none were reported in September. Sentinel-2 thermal satellite imagery frequently showed the progression of the active lava flows as a strong thermal anomaly descending the SE flank during October through late November and the SW flank during December, sometimes even through weather clouds (figure 54). The thermal anomalies were commonly accompanied by a gas-and-steam plume that drifted mainly E and NE. A total of 164 VAAC advisories were issued from 2 October through 31 December.

Figure 53. Strong and frequent thermal anomalies were detected in early October at Klyuchevskoy and continued through December 2020, as recorded by the MIROVA graph (Log Radiative Power). Courtesy of MIROVA.

Figure 54. Sentinel-2 thermal satellite images showing the progression of two lava flows (bright yellow-orange) originating from the summit crater at Klyuchevskoy from 4 October through December 2020. Crater incandescence was visible on 4 October (top left), which marked the beginning of the lava flow. By 31 October (top right) the active flow had traveled down the Apakhonchich chute on the SE flank, accompanied by a gas-and-steam plume that drifted NE. On 10 November (bottom left) the lava flow continued down the SE flank; the darker black color represents parts of the lava flow that began to cool. The gas-and-steam plume drifted E from the summit. On 25 December (bottom right) a new lava flow was observed descending the SW flank, also accompanied by a strong gas-and-steam plume. Sentinel-2 satellite images with “Atmospheric penetration” (bands 12, 11, 8A) rendering; courtesy of Sentinel Hub Playground.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Kamchatka Volcanological Station, Klyuchi, Kamchatka Krai, Russia (URL: http://volkstat.ru/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).

April 2021 (BGVN 46:04) Cite this Report

Ash emissions and lava flows during January-February, new NW-flank vent and flow February-March 2021

Klyuchevskoy, Kamchatka’s tallest volcano, has had over 100 recorded historical eruptions during the last 300 years characterized by major explosive and effusive events from summit and flank craters. Activity since April 2019 has consisted of ash plumes, Strombolian activity, and active lava flows on multiple flanks. Renewed Strombolian activity and lava flows began in October 2020 and continued into 2021, ending in late March. January-March 2021 is covered in this report with information provided by the Kamchatkan Volcanic Eruption Response Team (KVERT), the Kamchatka Volcanological Station, the Tokyo Volcanic Ash Advisory (VAAC), and satellite data.

Renewed explosive and effusive activity that began in October 2020 (BGVN 46:01) continued into 2021. A lava flow was active in the Kozyrevsky chute on the SW flank through mid-January; a flow again entered the SE-flank Apakhonchi chute in late January. Flow activity and Strombolian explosions from the summit ended in early February. A new vent near the base of the NW flank opened up on 17 February, sending a lava flow N and NW until the third week of March. Steam and gas emissions continued at the summit through the end of March. Explosive activity was very high during January 2021 with one or more ash explosions almost every day; significant ashfall occurred in mid-January. After a significant explosion in early February, subsequent ash plumes were all caused by resuspended ash from earlier events.

The MIROVA thermal anomaly graph for Klyuchevskoy closely follows the activity witnessed on the ground and seen in satellite images. The reappearance of very high levels of Radiative Power in early October 2020 coincided with the effusion of lava flows that remained active until early February 2021. A pulse of thermal energy that began in mid-February corresponded to the new vent on the NW flank about 5 km from the summit (figure 55). Activity stopped at the new vent in mid-March, but low levels of thermal energy remained from the cooling flows and from steam and gas emissions at the summit. MODVOLC thermal alert data included near-daily alerts from 1 January through 3 February. A second pulse of alerts was recorded from 20 February-19 March 2021.

Figure 55. The MIROVA thermal anomaly graph for Klyuchevskoy during April 2020-March 2021 reflects observed surface activity. High levels of Radiative Power in early October 2020 coincided with lava flows on the SE and SW flanks through early February 2021. Thermal anomalies more than 5 km from the summit that began later in February corresponded to effusion at the NW-flank vent. Courtesy of MIROVA.

The Tokyo VAAC reported an ash plume that rose to 7.6 km altitude and drifted SE on 1 January 2021. Two explosions the next day produced ash plumes that drifted SE at 6.1 km altitude. The Kamchatka Volcanological Station reported a landslide in the Apakhonchi chute on the SE flank on 2 January that generated an ash cloud which rose 1 km above the slope and drifted SE (figure 56). One or two daily explosions were reported through 7 January, generating ash plumes that rose to 6.1-7 km altitude and drifted in multiple different directions. KVERT reported ash plumes drifting as far as 70 km the first week and 90 km the second week of the month along with Strombolian and some Vulcanian activity (figure 57). Multiple explosions during 12-17 January produced ash that drifted NE or E at 6.1-7 km altitude, sometimes reaching 200 km from the volcano.

Figure 56. Ash rose from the flank of Klyuchevskoy on 2 January 2021 from a landslide in the Apakhonchi ravine on the SE flank while dense steam plumes rose from the summit crater. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

Figure 57. Strombolian activity sent ejecta tens of meters above the summit of Klyuchevskoy on 14 January 2021. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

A strong explosion on 18 January 2021 sent ash to 7.5 km altitude that drifted 500 km W. Two hours after the explosion ashfall began in Kozyrevsk village 50 km W. After a large snowstorm the next day 1 cm of ash was measured under 50 cm of fresh snow (figure 58). During 20-23 January ash plumes rose to 6.1-7.6 km altitude and drifted SW and NE. A large explosion on 24 January produced ash that initially rose to 8.5 km altitude and drifted W. Ash was later reported extending W at 10.4 km altitude and remained visible in satellite imagery into the next day, drifting 60 km N then NE. The explosion resulted in the collapse of areas along the edge of the Apakhonchi chute and produced multiple ash avalanches that descended 1,700 m from the summit in a few minutes (figure 59). During 28-31 January ash emissions rose to 3-6.1 km altitude and drifted NE and NW; KVERT reported an ash plume extending 92 km E on 29 January.

Figure 58. A layer of ash about 1 cm thick fell near Kozyrevsk village, 50 km W of Klyuchevskoy, after explosions on 18 January 2021; it was sampled two days later following a large snowstorm. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

Figure 59. Ash plumes descended the SE flank of Klyuchevskoy on 24 January 2021 from a collapse of the summit crater rim. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

At the beginning of January 2021, the lava flow in the Kozyrevsky chute on the SW flank that first appeared in images on 10 December 2020 remained active; it was visible in Sentinel 2 satellite imagery on 2, 4, and 7 January (figure 60). In the 14 and 17 January images it was about half as long as it had been previously. In a 22 January image a second flow in the Apakhonchi chute on the SE flank was partly visible under clouds, with a short flow remaining in the SW Kozyrevsky chute. KVERT first reported activity in the Apakhonchi chute on 21 January; satellite imagery on 24, 27, and 29 January and a photo from 28 January confirmed that it remained active while the flow in the Kozyrevsky chute had cooled (figure 61).

Figure 60. Lava flows were active on the SW and SE flanks of Klyuchevskoy during January 2021. An active flow descended the SW-flank Kozyrevsky chute on 4 January (left) and the SE-flank Apakhonchi chute on 29 January. Images use Atmospheric penetration rendering (bands 12, 11, 8a). Courtesy of Sentinel Hub Playground.

Figure 61. Lava continued to flow down the Apakhonchi chute on the SE flank of Klyuchevskoy on 28 January 2021. The image is misdated as 2020. To the left of Klyuchevskoy is Kamen and then the smaller Bezymianny lies farther to the left (summits are about 10 km apart). Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

There were far fewer ash emissions during February than January 2021. The Tokyo VAAC reported ash plumes on 2 and 3 February that rose to 5-6.1 km altitude and drifted E, NE, and W. An explosion on 4 February sent an ash plume ESE at 7 km altitude. Two large explosions on 5 February sent ash plumes that drifted ENE to 8.2 and 9.1 km altitude (figure 62). Continuous emissions that drifted W at 6.1 km altitude were noted on 7 February; KVERT reported satellite imagery of ash drifting 200 km W that day. KVERT issued a VONA reporting a significant decrease in seismicity overnight on 7-8 February. According to the seismological service, the volcanic tremor signal dropped to values less than 1 μm/s. The Kamchatka Volcanological Station reported that effusive activity stopped overnight during 8-9 February, and KVERT considered the summit eruption over. A small cinder cone had grown in the SE part of the summit crater during the eruption. During 12-14 February the Tokyo VAAC reported resuspended ash from the flanks at 4.6-5.2 km altitude. Sulfur dioxide emissions are difficult to detect in satellite instruments at high latitudes in winter. In spite of this, distinct SO₂ plumes were recorded on 4 and 15 February drifting away from the volcano (figure 63).

Figure 62. A dense ash emission from Klyuchevskoy on 5 February 2021 rose to over 8 km altitude drifted ENE. Continuous emissions during the next two days resulted in a plume visible in satellite imagery over 200 km W. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

Figure 63. SO₂ plumes were measured by the TROPOMI instrument on the Sentinel-5P satellite drifting NW and N from Klyuchevskoy on 4 and 15 February 2021. Courtesy of NASA Global Sulfur Dioxide Monitoring Page.

The lava flow on the SE flank was active in the Apakhonchi chute during the first week of February 2021, visible in satellite imagery on 1, 3, and 6 February. After that there was no sign of thermal activity at the summit or either the SW or SE chutes on 13 or 16 February. KVERT reported in a VONA on 17 February that a lateral vent on the NW flank began to open around 1130 UTC at an elevation of about 2,800 m near the Erman glacier. Snowfall during 17-19 February prevented video observation, but bright incandescence that appeared on 20 February suggested lava was flowing from the vent. Satellite imagery on 21 February confirmed incandescence and lava flows at two vents on the NW flank; they continued to grow and were both visible in images on 23 February (figure 64).

Figure 64. Sentinel-2 satellite infrared images with Atmospheric penetration rendering (bands 12, 11, 8a) showed the changes of effusive activity at Klyuchevskoy during February 2021. On 1 February (top left) a flow was active in the Apakhonchi chute on the SE flank. A steam plume rises from the head of the flow at the edge of the summit crater. By 16 February only steam emissions were present at the summit (top right). The first satellite image indicating a new vent on the NW flank was 21 February (bottom left). A closeup of the vent from 23 February showed two lava flows extending NNW (bottom right). Courtesy of Sentinel Hub Playground.

The lava flows on the NW flank melted parts of the Erman glacier and produced a lahar that was reported on 23 February 2021 traveling down the Krutenkaya River about 7 km from the village of Klyuchi. Strombolian ejecta sent bombs 50 m from the vents on 25 February and a small cinder cone had formed at the upper vent (figure 65). Satellite images showed two flows on 26 February but only one was active on 28 February (figure 66).

Figure 65. The new vent and lava flow on the NW flank of Klyuchevskoy produced Strombolian activity and phreatic explosions where the lava met the Erman glacier on 25 February 2021. A small pyroclastic cone is outlined in the glow from the Strombolian activity in the enlarged inset. Photos by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

Figure 66. Two flows were active from the vent on the NW flank of Klyuchevskoy on 26 February 2021 (left) but only one was growing in length on 28 February (right). Sentinel-2 images use Atmospheric penetration rendering (bands 12, 11, 8A). Courtesy of Sentinel Hub Playground.

An ash plume was reported by the Tokyo VAAC drifting E at 4.9 km altitude on 5 March 2021. KVERT noted that the ash was resuspended from material on the E flank and extended 375 km E of the volcano. KVERT reported that the lava flow on the NW flank remained active for the first two weeks of March 2021 with Strombolian activity at the cinder cone at the head of the flow. On 2 March a group of volcanologists from the IVS FEB RAS visited the site of the cinder cone and flow on the NW flank. The cone measured about 54 m high and 101 m wide at the base (figure 67). The lava flowed NW, penetrating into the Erman glacier, causing melting and mudflows in the Krutenkaya River (figure 68).

Figure 67. A team of volcanologists from IVS FEB RAS visited the site of the eruption on the NW flank of Klyuchevskoy on 2 March 2021. Ejecta from the growing pyroclastic cone at the vent rose tens of meters high and landed nearby. Photo by A. Elistratov, courtesy of Kamchatka Volcanological Station.

Figure 68. The lava flow on the NW flank of Klyuchevskoy persisted for the first two weeks of March 2021. Multiple branches of lava flowed NW from the new vent on 5 March 2021 (top left), and by 10 March it was focused into a single flow with steam plumes rising from multiple locations (top right). The path of the flow on 13 March was visible in both Atmospheric penetration rendering (bands 12, 11, and 8A) (bottom left) that showed the thermal anomaly and in the Natural color rendering (bands 4,3,2) (bottom right) that showed the dark area of the flow surrounded by ice and snow. Courtesy of Sentinel Hub Playground.

The Kamchatka Volcano Station reported on 14 March 2021 that the flow rate had decreased, and the lava was flowing N (figure 69). A field survey from the Station noted a decrease in activity at the NW-flank vent, now referred to as the Gorshkov vent, on 16 March (figure 70). They reported that only a small flow emerged from the W foot of the cone and flowed N (figure 71). Incandescent ejecta rose about 100 m above the cinder cone every few seconds. KVERT reported that the NW flank activity had stopped by 22 March. Weak incandescence was still observed over the cinder cone and lava flows in video images, but the intensity had decreased significantly. During the last week of March strong winds were responsible for plumes of resuspended ash from loose material on the SE flank near the Apakhonchi chute. On 25 March ash was visible in satellite imagery drifting E at 5.2-5.5 km altitude. KVERT reported it visible 72 km E from the volcano. Gas and steam emissions from the summit crater continued through the end of March (figure 72).

Figure 69. The NW flank flow at Klyuchevskoy shifted more towards the N on 14 March 2021 and was visible in a Sentinel-2 satellite image the next day (left). By 20 March the flow rate had diminished significantly, producing a much smaller thermal anomaly (right). Images use Atmospheric penetration rendering (bands 12, 11, 8a). Courtesy of Sentinel Hub Playground.

Figure 70. A team from the Kamchatka Volcanological Station visited the new cone and vent on the NW flank of Klyuchevskoy on 16 March 2021, noting that activity had decreased since a visit earlier in the month. The active flow is on the left below the cone. In this clear view to the N, beyond the cone Ushkovsky is on the left about 10 km away with the smaller Sredny cone in front of it, and Sheveluch is on the right about 75 km NE. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

Figure 71. The lava flow from the Gorshkov vent on the NW flank of Klyuchevskoy was slowly moving N from the W base of the cone when surveyed on 16 March 2021 by scientists from the Kamchatka Volcanological Station. Video by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

Figure 72. Gas and steam emissions from the summit crater of Klyuchevskoy are seen here on 24 March 2021. Photo by Y. Demyanchuk, courtesy of Kamchatka Volcanological Station.

A large plume of SO₂ drifted SW from Klyuchevskoy on 19 March 2021 and was still present the next day drifting E (figure 73). Multiple days of smaller but distinct SO₂ emissions were detected during February and March 2021.

Figure 73. A large plume of SO₂ drifted SW from Klyuchevskoy on 19 and 20 March 2021. A smaller plume drifted S on 28 March. Steam and gas emissions from the summit were the only noted activity after the lava flow from the vent on the NW flank had stopped advancing by 22 March. Courtesy of NASA Global Sulfur Dioxide Monitoring Page.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); Kamchatka Volcanological Station, Klyuchi, Kamchatka Krai, Russia (URL: http://volkstat.ru/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); NASA Global Sulfur Dioxide Monitoring Page, Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center (NASA/GSFC), 8800 Greenbelt Road, Goddard, Maryland, USA (URL: https://so2.gsfc.nasa.gov/).

December 2022 (BGVN 47:12) Cite this Report

Strombolian eruption in November 2022

Table 19. Dates reported by KVERT during September 2021-September 2022 when high winds resuspended loose ash on Klyuchevskoy’s flanks, prompting an Aviation Color Code increase.

Dates	Plume altitude	Drift
29 Sep 2021	3-5 km	75 km E
25-26 Aug 2022	--	205 km E
04-05 Sep 2022	3-4 km	180 km E
21-23 Sep 2022	3.5-4.5 km	460 km SE

Figure 74. Image of incandescence above the crater from renewed eruptive activity at Klyuchevskoy on 20 November 2022. Photo by Y. Demyanchuk, courtesy of KVERT.

Information Contacts: Kamchatka Volcanic Eruptions Response Team (KVERT), Far Eastern Branch, Russian Academy of Sciences, 9 Piip Blvd., Petropavlovsk-Kamchatsky, 683006, Russia (URL: http://www.kscnet.ru/ivs/kvert/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/).

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Synonyms

Cones

Feature Name

Feature Type

Elevation

Latitude

Longitude

Lavoyi Shish

Lava cone

Zabytaya, Mount

Lava cone

Craters

Feature Name

Feature Type

Elevation

Latitude

Longitude

Akademia Nauk

Fissure vent

Apakhonchich

Fissure vent

1500 m

Atlasov

Fissure vent

Belyankin
Beliankin

Fissure vent

1350 m

Bering

Fissure vent

Bilyukai
Biliukaya

Fissure vent

1000 m

Biokos'

Fissure vent

500 m

Bokovoi

Fissure vent

Bulochka

Fissure vent

Bylinkina
Bylinkinoy

Fissure vent

950 m

Ditmar-Taushits-Sosed

Fissure vent

Faina

Fissure vent

Gorshok

Fissure vent

Holm

Fissure vent

IVth National Volcanoligical Congress

Fissure vent

3600 m

Karpinskiy

Fissure vent

Kell

Fissure vent

Kirgurich

Fissure vent

500 m

Kozei Group

Fissure vent

Krasheninnikov

Fissure vent

1000 m

Krug

Fissure vent

Kryzhanovskiy
Kryshanovskogo

Fissure vent

1380 m

Lepshka

Fissure vent

Lesnoi

Fissure vent

Levashov

Fissure vent

Loewinsson-Lessin

Fissure vent

Malenkiy

Fissure vent

Malysh

Fissure vent

March

Fissure vent

Nevidimka

Fissure vent

Nezametnyi

Fissure vent

Ochki

Fissure vent

Ostanets

Fissure vent

Otkrytyi

Fissure vent

Peshchernyi

Fissure vent

Piip

Fissure vent

1900 m

Podkova

Fissure vent

Pogrebennyi

Fissure vent

Predskanzannyi

Fissure vent

2875 m

Predvidennoye

Fissure vent

3800 m

Pribrezhnyi

Fissure vent

Propushchennyi

Fissure vent

Sedlo

Fissure vent

Shmalev

Fissure vent

Sizmos

Fissure vent

Skuridin

Fissure vent

Slyunin

Fissure vent

Srezannyi

Fissure vent

Steller

Fissure vent

Tiranus

Fissure vent

Tretiy

Fissure vent

Tuyla
Tuila

Fissure vent

500 m

Vernadskiy
Bernadskogo

Fissure vent

1360 m

Vosmyorka

Fissure vent

Yubileinoye
Jubilee

Fissure vent

1400 m

Zabytyi

Fissure vent

Zatoplennyi

Fissure vent

Zavaritsky

Fissure vent

1000 m

Basic Data

Volcano Number

Last Known Eruption

Elevation

Latitude
Longitude

300260

2023 CE

4,754 m / 15,597 ft

56.056°N
160.642°E

Morphology

Volcano Landform
Composite

Volcano Types
Stratovolcano
Pyroclastic cone(s)

Rock Types

Major
Basalt / Picro-Basalt
Andesite / Basaltic Andesite

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km

0
0
292
12,406

Geological Summary

Klyuchevskoy is the highest and most active volcano on the Kamchatka Peninsula. Since its origin about 6,000 years ago, this symmetrical, basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. It rises above a saddle NE of Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred during approximately the past 3,000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 and 3,600 m elevation. Eruptions recorded since the late 17th century have resulted in frequent changes to the morphology of the 700-m-wide summit crater. These eruptions over the past 400 years have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.

This volcano is located within the Volcanoes of Kamchatka, a UNESCO World Heritage property.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Adushkin V V Zykov Y N, Fedotov S A, 1995. Mechanism of volcanic slope failure. Assessment of potential collapse and debris avalanches at Klyuchevskoi volcano. Volc Seism, 16: 667-684 (English translation).

Basharina L A, 1965. Gases of Kamchatka volcanoes. Bull Volcanol, 28: 95-106.

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Eruptive History

There is data available for 110 confirmed Holocene eruptive periods.

2023 Jun 22 - 2023 Dec 31 Confirmed Eruption VEI: 3

Episode 1 | Eruption

2023 Jun 22 - 2023 Dec 31

Evidence from Observations: Reported

List of 6 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
2023 Jun 22	- - - -	Incandescent ejecta	A minor Strombolian eruption began at 2323 on 22 June and a bright thermal anomaly was visible in satellite images.
2023 Jun 22	- - - -	Thermal Anomaly	On 22 June a bright thermal anomaly was visible in satellite images.
2023 Jul 19	- - - -	Lava flow	A new lava flow was first seen on 19 July advancing down the Apakhonchich drainage on the SE flank.
2023 Sep 28	2023 Oct 11	Lava fountains	During 28 September-11 October lava fountaining fed flows that alternately advanced down the Apakhonchichsky and Kozyrevsky drainages on the S and SE flanks.
2023 Oct 31	2023 Nov 1	Ash Plume	Ash plumes rose as high as 14 km altitude (9 km above the summit) and drifted as far as 2,255 km ESE during 31 October-1 November.
2023 Oct 31	2023 Nov 1	VEI (Explosivity Index)	VEI 3

2022 Nov 17 - 2022 Nov 25 (?) Confirmed Eruption VEI: 1

Episode 1 | Eruption

2022 Nov 17 - 2022 Nov 25 (?)

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Lava fountains
2022 Dec 1	- - - -	Ash Plume	Possible ash plumes rose as high as 150 m above the summit.
2022 Dec 1	- - - -	VEI (Explosivity Index)	VEI 1

2019 Apr 9 - 2021 Mar 20 Confirmed Eruption VEI: 2

Episode 1 | Eruption

2019 Apr 9 - 2019 Aug 2

Evidence from Observations: Reported

List of 1 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	VEI (Explosivity Index)

Episode 2 | Eruption

2019 Oct 24 - 2020 Jul 3

Evidence from Observations: Reported

List of 1 Events for Episode 2

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	VEI (Explosivity Index)

Episode 3 \| Eruption
2020 Oct 2 - 2021 Mar 20				Evidence from Observations: Reported

2015 Aug 28 - 2018 Jul 14 Confirmed Eruption VEI: 3

Episode 1 | Eruption

Summit crater

2015 Aug 28 - 2015 Dec 31

Evidence from Observations: Reported

List of 9 Events for Episode 1 at Summit crater

Start Date	End Date	Event Type	Event Remarks
2015 Aug 28	- - - -	Incandescent ejecta	KVERT reported that a webcam recorded crater incandescence at Klyuchevskoy at 0344, indicating the onset of Strombolian activity.
2015 Sep 8	2015 Sep 10	Incandescent ejecta	According to video data, moderate gas-steam and Strombolian activity was noted.
2015 Sep 11	2015 Sep 24	Thermal Anomaly	Satellite data reported by KVERT showed a thermal anomaly over the volcano on 11, 14-18, and 24 September.
2015 Sep 13	2015 Sep 14	Ash Plume	KVERT reported a diffuse ash plume at about 1.5 km altitude drifting E.
2015 Sep 13	- - - -	VEI (Explosivity Index)	VEI 1
2015 Oct 10	2015 Oct 23	Incandescence	Intermittent incandescence was observed at the summit crater.
2015 Nov 20	- - - -	Thermal Anomaly	Satellite data by KVERT showed a thermal anomaly over the volcano.
2015 Dec 5	2015 Dec 31	Thermal Anomaly	Satellite data by KVERT showed a thermal anomaly over the volcano on 5, 17, 19, 23, 29, and 31 December.
2015 Dec 16	- - - -	Incandescence	According to videodata, KVERT observed incandescence at the summit.

Episode 2 | Eruption

Summit and SE flank

2016 Apr 3 - 2017 Sep 18

Evidence from Observations: Reported

List of 140 Events for Episode 2 at Summit and SE flank

Start Date	End Date	Event Type	Event Remarks
2016 Mar 25	2016 Mar 30	Thermal Anomaly	KVERT reported that a weak thermal anomaly was detected over the volcano during 25 and 29-30 March.
2016 Apr 3	2016 Apr 21	Incandescent ejecta	Strong Strombolian activity began at 2325 on 3 April and continued for multiple weeks.
2016 Apr 5	- - - -	Thermal Anomaly	Satellite images began registering a bright thermal anomaly.
2016 Apr 8	2016 Apr 15	Thermal Anomaly	Multiple daily MODVOLC thermal alerts were issued.
2016 Apr 8	2016 Jul 1	Thermal Anomaly	KVERT reported that satellite images showed an intense daily thermal anomaly over the volcano.
2016 Apr 15	- - - -	Ash Plume	Strong gas-steam plumes containing ash extended for about 55 km to the NE.
2016 Apr 18	2016 Apr 20	Thermal Anomaly	Four MODVOLC thermal alerts were issued.
2016 Apr 21	2016 Apr 30	Lava flow	Satellite and video data showed a lava flow effusing on the SE flank, moving down the Apakhonchich drainage.
2016 Apr 23	2016 Apr 24	Ash Plume	An ash cloud that drifted about 500 km SW.
2016 Apr 24	2016 Jun 2	Thermal Anomaly	Multiple near-daily MODVOLC thermal alerts were issued.
2016 Apr 25	- - - -	Explosion	At 0140 a strong explosion generated an ash plume that rose to altitudes of 8-9 km and, by 1428, had drifted over 450 km SW.
2016 Apr 25	- - - -	Ash Plume	At 0140 a strong explosion generated an ash plume that rose to altitudes of 8-9 km and, by 1428, had drifted over 450 km SW.
2016 Apr 25	- - - -	VEI (Explosivity Index)	VEI 2
2016 May 1	2016 May 31	Lava flow	Satellite and video data showed a lava flow effusing on the SE flank, moving down the Apakhonchich drainage.
2016 May 2	- - - -	Ash Plume	Satellite images showed an ash cloud that drifted 88 km SE on 2 May.
2016 May 13	2016 May 16	Ash Plume	Satellite images showed ash plumes drifting as far as 80 km E and SE on 13 and 16 May.
2016 Jun 1	2016 Jun 30	Lava flow	Satellite and video data showed a lava flow effusing on the SE flank, moving down the Apakhonchich drainage.
2016 Jun 5	2016 Aug 17	Thermal Anomaly	Multiple near-daily MODVOLC thermal alerts were issued.
2016 Jun 13	- - - -	Ash Plume	Satellite images showed an ash plume drifting almost 50 km W.
2016 Jun 18	- - - -	Ash Plume	Satellite images showed an ash plume drifting almost 30 km E.
2016 Jun 24	- - - -	Ash Plume	Ash plumes drifted W and NW.
2016 Jun 24	- - - -	Avalanche	Two rock avalanches down the Apakhonchich drainage were recorded by a webcam at 2115 and 2350.
2016 Jun 27	2016 Jun 28	Degassing	Satellite images showed gas-and-steam plumes that drifted about 60 km E and W.
2016 Jul 1	2016 Jul 31	Lava flow	A lava flow traveled down the Apakhonchich drainage.
2016 Jul 1	2016 Jul 31	Bombs	Volcanic bombs were ejected 200-300 m above the summit crater and 50 m above a cinder cone, and landed in the Apakhonchich drainage on the SE flank.
2016 Jul 1	2016 Aug 19	Thermal Anomaly	KVERT reported that satellite images showed a large and intense daily thermal anomaly at the volcano.
2016 Jul 2	2016 Jul 5	Ash Plume	Satellite images showed ash plumes drifting 350 km SW, S, and SE.
2016 Jul 6	- - - -	Explosion	Video data showed that activity intensified; strong explosions generated ash plumes that rose as high as 7.5 km altitude.
2016 Jul 6	2016 Jul 7	Ash Plume	Video data showed that activity intensified on 6 July; strong explosions generated ash plumes that rose as high as 7.5 km altitude. Satellite images showed dense ash plumes drifting 400 km SE and E.
2016 Jul 11	2016 Jul 12	Ash Plume	Satellite images showed ash plumes drifting 170 km NE.
2016 Jul 18	2016 Jul 19	Ash Plume	Satellite images showed ash plumes drifting over 265 km SW and W.
2016 Jul 22	2016 Jul 26	Ash Plume	Satellite images showed ash plumes drifting over 140 km E during 22-23 and 26 July.
2016 Jul 31	2016 Aug 4	Ash Plume	Satellite images showed ash plumes drifting about 200 km NE, E, and NW during 31 July, 1 August, and 3-4 August.
2016 Aug 1	2016 Aug 26	Lava flow	A lava flow traveled down the Apakhonchich drainage.
2016 Aug 1	2016 Aug 31	Bombs	Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the SE flank.
2016 Aug 9	2016 Aug 11	Ash Plume	Satellite images showed ash plumes drifting about 370 km SE and W during 9 and 11 August.
2016 Aug 19	2016 Nov 3	Thermal Anomaly	KVERT reported that satellite images showed a large and bright daily thermal anomaly at the volcano.
2016 Aug 20	2016 Sep 16	Thermal Anomaly	Tens of near-daily MODVOLC thermal alerts were issued.
2016 Aug 26	2016 Sep 2	Ash Plume	Satellite images showed ash plumes drifting 230 km NE, SE, S, and SW.
2016 Aug 26	2016 Sep 23	Lava flow	A lava flow traveled down the Apakhonchich drainage and also down the SW flank.
2016 Sep 1	2016 Sep 23	Bombs	Volcanic bombs that were ejected above the summit crater and the cinder cone landed in the Apakhonchich drainage on the SE flank.
2016 Sep 7	- - - -	Explosion	At 0943 and 1443 explosions generated ash plumes that rose to altitudes of 6.5-7.5 km and drifted as far as 75 km SSW and ESE. Explosions at 1804 produced ash plumes that rose as high as 7 km altitude and drifted 45 km NE.
2016 Sep 7	- - - -	Ash Plume	At 0943 and 1443 explosions generated ash plumes that rose to altitudes of 6.5-7.5 km and drifted as far as 75 km SSW and ESE. Explosions at 1804 produced ash plumes that rose as high as 7 km altitude and drifted 45 km NE.
2016 Sep 8	- - - -	Explosion	At 0034, 0758, 1341, and 1850 explosions generated ash plumes that rose to altitudes of 7-7.5 km and drifted as far as 145 km NE, NW, W, and SW.
2016 Sep 8	- - - -	Ash Plume	At 0034, 0758, 1341, and 1850 explosions generated ash plumes that rose to altitudes of 7-7.5 km and drifted as far as 145 km NE, NW, W, and SW.
2016 Sep 9	- - - -	Explosion	Ash plumes from explosions rose to altitudes of 3-5 km and drifted 315-535 km SW.
2016 Sep 9	- - - -	Ash Plume	Ash plumes from explosions rose to altitudes of 3-5 km and drifted 315-535 km SW; ash plumes continued to drift and dissipate over the Avachinsky bay.
2016 Sep 9	- - - -	Ashfall	Minor ash deposits at Koryaksky and Avachinsky volcanoes were detected during 2100-2140.
2016 Sep 10	2016 Sep 15	Ash Plume	On 10, 13, and 15 September ash plumes rose as high as 7 km altitude and drifted 50 km NE and SE.
2016 Sep 19	2016 Nov 2	Thermal Anomaly	Tens of near-daily MODVOLC thermal alerts were issued.
2016 Sep 20	2016 Sep 22	Explosion	Explosions generated ash plumes that rose as high as 7 km altitude and drifted 100 km SW, E, and SE.
2016 Sep 20	2016 Sep 22	Ash Plume	Explosions generated ash plumes that rose as high as 7 km altitude and drifted 100 km SW, E, and SE.
2016 Sep 23	2016 Sep 24	Explosion	Explosions generated ash plumes that rose as high as 6 km altitude and drifted 165 km in multiple directions.
2016 Sep 23	2016 Sep 24	Ash Plume	Explosions generated ash plumes that rose as high as 6 km altitude and drifted 165 km in multiple directions.
2016 Sep 23	2016 Sep 30	Ash Plume	Ash emissions rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank.
2016 Sep 23	2016 Nov 3	Lava flow	A lava flow traveled down the Apakhonchich drainage. Lava effusion onto the flanks was last noted on 3 November.
2016 Sep 30	2016 Oct 7	Explosion	Satellite images showed ash plumes from explosions that rose to altitudes of 5-6 km and drifted 260 km E.
2016 Sep 30	2016 Oct 7	Ash Plume	Satellite images showed ash plumes from explosions that rose to altitudes of 5-6 km and drifted 260 km E.
2016 Sep 30	2016 Nov 4	Ash Plume	Gas-and-steam emissions with variable amounts of ash rose from the summit crater and from the cinder cone in the Apakhonchich drainage on the E flank.
2016 Oct 7	2016 Oct 12	Explosion	Satellite images showed ash plumes from explosions that rose to altitudes of 5-6 km and drifted 300 km N, NE, E, and SE.
2016 Oct 7	2016 Oct 12	Ash Plume	Satellite images showed ash plumes from explosions that rose to altitudes of 5-6 km and drifted 300 km N, NE, E, and SE.
2016 Oct 14	2016 Oct 19	Explosion	Satellite images showed ash plumes from explosions that rose to altitudes of 5-6 km and drifted 300 km NW, E, and SE during 14 and 18-19 October.
2016 Oct 14	2016 Oct 19	Ash Plume	Satellite images showed ash plumes from explosions that rose to altitudes of 5-6 km and drifted 300 km NW, E, and SE during 14 and 18-19 October.
2016 Oct 20	2016 Oct 27	Explosion	Satellite images showed ash plumes from explosions that rose to altitudes of 5-7 km and drifted 335 km E, N, NW, and W during 20-21 and 23-27 October.
2016 Oct 20	2016 Oct 27	Ash Plume	Satellite images showed ash plumes from explosions that rose to altitudes of 5-7 km and drifted 335 km E, N, NW, and W during 20-21 and 23-27 October.
2016 Oct 30	2016 Nov 3	Explosion	Gas, steam, and ash plumes from explosions rose to altitudes of 5-8 km and drifted 277 km E and SE.
2016 Oct 30	2016 Nov 3	Ash Plume	Gas, steam, and ash plumes from explosions rose to altitudes of 5-8 km and drifted 277 km E and SE.
2016 Nov 3	2016 Nov 4	Ash Plume	Ash plumes were last detected in satellite images during 3-4 November.
2016 Nov 3	2016 Nov 4	Incandescent ejecta	Strombolian activity was observed in the crater.
2016 Nov 4	- - - -	Thermal Anomaly	KVERT reported that the thermal anomaly was reduced.
2016 Nov 17	- - - -	Ash Plume	KVERT reported that an ash plume visible in satellite images rose to an altitude of 5 km and drifted almost 60 km WNW.
2016 Nov 18	2016 Nov 25	Thermal Anomaly	KVERT reported that a daily thermal anomaly was visible in satellite images.
2016 Dec 23	2016 Dec 30	Ash Plume	A moderate gas-steam plume containing small amounts of ash was observed all week.
2016 Dec 23	2016 Dec 30	Thermal Anomaly	Satellite data by KVERT showed a thermal anomaly over the volcano all week.
2016 Dec 31	- - - -	Ash Plume	KVERT reported that an ash plume drifted for about 41 km to the SE from the volcano on 31 December.
2017 Jan 1	- - - -	Explosion	Based on satellite and webcam images KVERT reported that explosions generated ash plumes that rose to an altitude of 5 km and drifted 114 km SE.
2017 Jan 1	- - - -	Ash Plume	Based on satellite and webcam images KVERT reported that explosions generated ash plumes that rose to an altitude of 5 km and drifted 114 km SE.
2017 Jan 1	2017 Mar 9	Thermal Anomaly	Satellite data by KVERT showed a thermal anomaly over the volcano on days when it was not obscured by clouds.
2017 Jan 9	2017 Jan 10	Ash Plume	Based on HIMAWARI-8 satellite data, the Tokyo VAAC reported a possible ash emission at 0230 UTC extending NW at 5.5 km altitude. A new possible emission was reported at 0620 UTC extending N at 6.7 km altitude. Ash emissions were continuously observed on satellite imagery and confirmed by KVERT, UHPP, and KBGS the following day. KVERT reported that the plumes drifted 160 km ESE.
2017 Jan 17	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 0120 UTC that extended SW from the volcano at 4.9 km altitude. It dissipated after a few hours.
2017 Jan 21	2017 Jan 23	Ash Plume	KVERT reported that gas-steam plumes containing ash extended for about 90 km to the east from the volcano.
2017 Jan 22	- - - -	Ash Plume	Based on HIMAWARI-8 satellite, KVERT and UHPP information, the Tokyo VAAC reported an ash emission at 0536 UTC extending E from the summit at 5.5 km altitude with continuing ash emissions for about six hours.
2017 Jan 23	- - - -	Ash Plume	Based on HIMAWARI-8 satellite and KBGS information, the Tokyo VAAC reported an ash emission at 0035 UTC extending ENE from the summit at 7 km altitude. Ash emissions were continuously observed on satellite imagery for about six hours.
2017 Feb 17	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the TOKYO VAAC reported a possible eruption observed at 0410 UTC extending NE from the summit at 5.5 km altitude. The ash dissipated within four hours.
2017 Mar 1	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1300 UTC extending NW from the summit at 6.1 km altitude. Ash was continuously observed in satellite imagery for about six hours.
2017 Mar 2	- - - -	Ash Plume	According to KVERT visual data, ash bursts up to 8-9 km were observed. Satellite data; ash plumes drifted for about 110 km to the NW and NE.
2017 Mar 2	2017 Mar 3	Ash Plume	Based on HIMAWARI-8 satellite and KBGS information, the Tokyo VAAC reported an ash emission at 0142 UTC extending ENE at 8.2 km altitude. A short time later, based on HIMAWARI-8, KVERT, UHPP and KBGS information they reported an eruption at 0205 UTC extending NE at 9.1 km altitude. Continuous ash emissions were observed. Based on HIMAWARI-8, possible ash emissions were observed at 1300 UTC and 1800 UTC extending N and NE at 6.1 km altitude. Based on HIMAWARI-8 and KBGS information, an emission was reported at 1940 UTC extending NNE at 7.0 km altitude. Based on HIMAWARI-8 information a possible ash emission was reported at 0120 on 3 March extending SE at 5.2 km altitude. Ash was dissipated by 0520 UTC.
2017 Mar 8	- - - -	Ash Plume	Based on HIMAWARI-8, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 2345 UTC that extended WNW at 5.5 km altitude. KVERT reported that the ash plume drifted for about 20 km to the NW from the volcano.
2017 Mar 10	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1040 UTC extending NE at 6.1 km altitude. Ash had dissipated in satellite imagery by 2330 UTC.
2017 Mar 11	2017 Mar 24	Thermal Anomaly	Satellite data by KVERT showed a weak thermal anomaly over the volcano.
2017 Mar 25	2017 Apr 11	Thermal Anomaly	Satellite data by KVERT showed a thermal anomaly over the volcano when it was not obscured by clouds.
2017 Mar 27	2017 Apr 4	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1750 UTC extending NE at 6.1 km altitude. KVERT confirmed the emissions continuing the next day, at 7 km altitude. Emissions were reported extending SW at 7.6 km altitude at 0010 UTC on 29 March, and were continuously observed at that altitude through 2320 UTC on 3 April. A possible eruption was reported at 0030 UTC on 4 April extending SE at 6.7 km altitude with continuing emissions which had dissipated by 1120 UTC. KVERT reported that the ash plume drifted for about 400 km to the SW, NW, E, NE and SE from the volcano.
2017 Apr 14	2017 Jul 20	Thermal Anomaly	Satellite data by KVERT showed an intermittent weak thermal anomaly over the volcano.
2017 Apr 22	2017 Apr 23	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1200 UTC extending SW at 5.8 km altitude. Continuing emissions were confirmed by KVERT until no longer observed in satellite imagery by 1120 UTC on 23 April. KVERT reported that ash plumes extended for about 125 km to the SW from the volcano.
2017 Apr 23	2017 Apr 24	Ash Plume	Based on HIMAWARI-8 satellite and KBGS information, the Tokyo VAAC reported an ash emission at 2015 UTC extending SW at 7 km altitude with continuing emissions that dissipated by 0520 UTC on 24 April. KVERT reported that ash plumes extended for about 125 km to the SW from the volcano.
2017 Apr 24	2017 Apr 25	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1030 UTC extending W at 6.1 km altitude. Ash was continuously observed in satellite imagery. A new possible ash emission at 0240 UTC on 25 April extended SW at 5.5 km altitude until it dissipated by 1120 UTC on 25 April. KVERT reported that ash plumes extended for about 125 km to the SW from the volcano.
2017 Apr 30	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, the Tokyo VAAC reported an ash emission at 0512 UTC that extended SSE at 6.1 km altitude. A new possible ash emission at 0700 UTC extended south at 6.1 km altitude with emissions continuing until they dissipated by 1730 UTC.
2017 May 1	2017 May 2	Ash Plume	Based on HIMAWARI-8 information, the Tokyo VAAC reported a possible ash emission at 0930 UTC extending E at 7 km altitude. Ash emissions continued until they dissipated by 0530 UTC on 2 May. KVERT reported that an ash plume extended for about 52 km to the E from the volcano.
2017 May 4	- - - -	Ash Plume	Based on HIMAWARI-8 satellite and UHPP information, the Tokyo VAAC reported an ash emission at 2335 UTC that extended SSE at 4.9 km altitude that was not identifiable in satellite data.
2017 May 5	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission observed at 0340 UTC extending SE at 5.5 km altitude with ash continuously observed in satellite data until it dissipated by 1720 UTC. Satellite data by KVERT showed that ash plumes extended for about 270 km to the SE.
2017 May 6	- - - -	Ash Plume	Based on HIMAWARI-8, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 0431 UTC extending E at 8.2 km altitude. Ash was not identifiable from satellite data. Satellite data by KVERT showed ash plumes extended for about 270 km to the SE.
2017 May 10	2017 May 11	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission observed at 2120 UTC extending W at 5.2 km altitude. KVERT confirmed the continuing ash emission extending WNW at 5.5 km altitude. Ash was no longer identifiable in satellite imagery by 1120 UTC the next day. Satellite data by KVERT showed ash plumes extended for about 270 km to the NW.
2017 May 17	2017 May 19	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1900 UTC extending NE at 6.1 km altitude. Emissions were confirmed by KVERT and KBGS continuing at 7.3 km altitude until 0310 UTC on 19 May. The Anchorage VAAC confirmed residual ash moving SE at 6.1 km altitude at 0600 UTC, which had dissipated by 1154 UTC. KVERT reported that the ash plume extended for about 180 km to the N and NE from the volcano.
2017 May 21	- - - -	Ash Plume	Based on HIMAWARI-8, KVERT, and UHPP information, the Tokyo VAAC reported that an ash emission at 0155 UTC extended SE at 6.1 km altitude that was not visible in satellite imagery.
2017 Jun 1	2017 Jun 2	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 0540 UTC extending NE at 5.5 km altitude. It was no longer identifiable in satellite imagery by 1130 UTC. Another possible ash emission was observed at 1150 UTC extending S at 5.5 km altitude. Another possible ash emission was observed at 1420 UTC extending SW at 6.1 km altitude. Continuing emissions were confirmed by KVERT and KBGS at 0000 UTC on 2 June extending SW at 6.1 km altitude. Ash emissions were last identified in satellite imagery at 1120 UTC on 2 June when they were obscured by meteoric clouds. KVERT reported that the ash plume drifted for about 400 km to the SSE over Petropavlovsk-Kamchatsky and Elizovo, but ashfall was not observed due to the weak content of ash particles in the plume.
2017 Jun 3	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1240 UTC extending E at 5.5 km altitude. They were no longer identifiable in satellite imagery by 2320 UTC.
2017 Jun 4	2017 Jun 5	Ash Plume	Based on HIMAWARI-8 satellite imagery, the Tokyo VAAC observed a possible ash emission at 1720 UTC extending NE at 5.2 km altitude. Continuing emissions were confirmed by KVERT at 2320 UTC. They had dissipated by 1750 UTC on 5 June. KVERT reported that ash plumes drifted for about 325 km to the NE, SE and SW.
2017 Jun 6	2017 Jun 8	Ash Plume	Based on HIMAWARI-8 satellite imagery, the Tokyo VAAC observed a possible ash emission at 2300 UTC extending SW at 5.5 km altitude. Continuing emissions were confirmed by KVERT until they were not identifiable by 0520 UTC on 8 June. KVERT reported that ash plumes drifted for about 325 km to the NE, SE and SW all week.
2017 Jun 8	2017 Jun 13	Ash Plume	Based on HIMAWARI-8 satellite imagery, the Tokyo VAAC observed a possible ash emission at 0720 UTC extending SW at 5.5 km altitude. KVERT confirmed continuing emissions at 0520 UTC on 9 June. KBGS confirmed a new ash emission at (?)2200 UTC extending WSW at 7.0 km altitude which were confirmed by KVERT and UHPP at 2320 UTC. Continuing emissions were reported by HIMAWARI-8, KVERT, UHPP and KBGS sources through 2320 UTC on 11 June. KVERT and KBGS confirmed a new ash emission at 0335 UTC on 12 June that extended SSW at 7.6 km altitude. Another new ash emission at 0525 UTC extended S at 8.2 km altitude. Ash emissions were no longer identifiable in satellite imagery by 0540 UTC on 13 June. KVERT reported that ash plumes drifted for about 580 km to the SW and SE.
2017 Jun 13	2017 Jun 16	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed an ash plume at 1000 UTC extending W at 7.0 km altitude. It was continuously observed in satellite imagery through 0000 UTC on 14 June. A new possible eruption was observed in satellite imagery at 0320 UTC extending SW at 6.1 km altitude. KBGS an KVERT confirmed continuing emissions at 2110 UTC and 2320 UTC at 7.0 km altitude through 0530 UTC on 16 June. They had dissipated by 1120 UTC. KVERT reported ash plumes drifted for about 580 km to the SW and SE from the volcano.
2017 Jun 17	2017 Jun 18	Ash Plume	Based on HIMAWARI-8, KVERT and UHPP information, the Tokyo VAAC reported an ash emission at 0029 UTC extending E at 6.1 km altitude. Ash emissions continued at least through 1720 UTC on 18 June and were no longer identifiable by 2320 UTC. KVERT reported that ash plumes drifted for about 300 km to the E.
2017 Jun 21	- - - -	Ash Plume	Based on HIMAWARI-8 information, the Tokyo VAAC observed a possible ash emission at 0540 UTC extending SW at 5.5 km altitude. Continuing emissions were observed through 1720 UTC and had dissipated in satellite imagery by 2320 UTC. KVERT reported ash plumes drifted for about 300 km to the W.
2017 Jun 22	- - - -	Ash Plume	Based on HIMAWARI-8 information, the Tokyo VAAC observed a possible ash emission at 0500 UTC extending W at 5.5 km altitude. Emission were continuing through 1120 UTC, but were no longer identifiable by 2320 UTC. KVERT reported ash plumes drifted for about 300 km to the W.
2017 Jun 24	2017 Jun 25	Ash Plume	Based on HIMAWARI-8, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 2050 UTC extending S at 5.2 km altitude. Emissions were continuously observed through 0520 UTC on 25 June and were not identifiable in satellite imagery by 1120 UTC. KVERT reported that ash plumes drifted for about 112 km to the S.
2017 Jun 26	2017 Jun 27	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 0810 UTC extending S at 5.5 km altitude. Continuing emissions were observed through 1720 UTC. KVERT and UHPP reported ash emissions at 2208 UTC extending SE at 6.1 km altitude that were continuing through 0520 on 27 June and not indentifiable in satellite imagery by 1120 UTC. KVERT reported ash plumes drifted for about 112 km to the SE.
2017 Jun 27	- - - -	Ash Plume	Based on HIMAWARI-8 satellite imagery, the Tokyo VAAC observed a possible ash emission at 1750 UTC extending SW at 6.1 km altitude. It was no longer identifiable in satellite imagery by 2320 UTC.
2017 Jun 28	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 0120 UTC extending SW at 5.2 km altitude. Emissions were continuing through 1120 UTC and had dissipated by 1750 UTC.
2017 Jul 1	2017 Jul 2	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed an ash emission at 0300 UTC extending S at 5.2 km altitude. KVERT confirmed continuing emissions at 1120 UTC. A new ash emission was reported by KVERT at 2150 UTC extending ESE at 6.1 km altitude. Emissions were continuing at 1720 UTC on 2 July, and had dissipated by 2320 UTC. KVERT reported that ash plumes drifted for about 160 km to the SE.
2017 Jul 3	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, the Tokyo VAAC reported an ash emission at 0010 UTC extending E at 6.1 km altitude that was not identifiable in satellite data.
2017 Jul 3	2017 Jul 4	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 2300 UTC extending NE at 5.5 km altitude. It was continuously observed in satellite imagery at 0520 UTC on 4 July and was not identifiable in satellite imagery by 1120 UTC.
2017 Jul 5	2017 Jul 8	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 0900 UTC extending SW at 5.5 km altitude. Continuing emissions were confirmed by KVERT at 2320 UTC. Continuing emissions were reported through 1720 on 7 July. A new emission was reported by KBGS at 2338 UTC extending E at 6.1 km altitude. It was no longer identifiable in satellite imagery by 0520 on 8 July. KVERT reported that ash plumes drifted for about 160 km to the SW.
2017 Jul 11	- - - -	Ash Plume	Based on HIMAWARI-8 satellite, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 0105 UTC extending SE at 5.2 km altitude that was not identifiable in satellite imagery.
2017 Jul 12	- - - -	Ash Plume	Based on HIMAWARI-8 satellite and KVERT information, the Tokyo VAAC reported an ash emission at 0050 UTC extending SSE at 5.2 km altitude. Ash emissions were continuing at 1120 UTC but were not identifiable in satellite data at 1730 UTC. KVERT reported that ash plumes drifted for about 50 km to the SE.
2017 Jul 17	2017 Jul 21	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed an ash emission at 1730 UTC extending S at 5.5 km altitude. The emission was confirmed by KVERT and KBGS by 2030 extending SE at 6.1 km altitude. Continuing emissions were observed through 1720 UTC on 20 July, possibly continuing through 0520 UTC on 21 July. They were dissipated or obscured by 1150 UTC. KVERT reported that ash plumes extended for about 300 km to the SW, SE, E, and NE.
2017 Jul 22	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1950 UTC extending NE at 5.2 km altitude. It was not identifiable in satellite imagery at 2320 UTC.
2017 Jul 23	2017 Jul 24	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1710 UTC extending NE at 6.1 km altitude. KVERT confirmed possible ash emissions continuing at 0520 UTC on 24 July. Emissions continued through 1120 UTC and were not identifiable in satellite imagery by 1720 UTC. KVERT reported that ash plumes extended for about 120 km to the E and NE.
2017 Aug 1	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, the Tokyo VAAC reported an ash emission at 2052 UTC extending S at 6.1 km altitude that was not identifiable in satellite imagery. KVERT reported that ash plumes extended for about 65 km to the SW.
2017 Aug 2	2017 Aug 3	Ash Plume	Based on HIMAWARI-8 satellite and KVERT information, the Tokyo VAAC reported an ash emission at 2230 UTC extending S at 5.2 km altitude. Emissions were not identifiable in satellite imagery by 0520 UTC on 3 August. KVERT reported that ash plumes extended for about 250 km to the ESE from the volcano.
2017 Aug 3	2017 Aug 5	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1930 UTC extending SE at 5.5 km altitude. KVERT confirmed continuing emissions at 2320 UTC. Emissions were continuing at 1720 on 4 August. A new ash emission was reported by KBGS at 2010 UTC extending E at 6.1 km altitude. Emissions were continuing at 2320 but were no longer identifiable in satellite imagery by 0520 on 5 August.
2017 Aug 7	- - - -	Ash Plume	Based on HIMAWARI-8 satellite, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 0110 UTC extending SE at 5.5 km altitude. Continuing emissions were reported at 0520 UTC but were not identifiable in satellite imagery by 1120 UTC. KVERT showed ash plumes extended for about 300 km to the SW, SE, and NE.
2017 Aug 7	2017 Aug 8	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1740 UTC extending SE at 5.5 km altitude. KVERT confirmed continuing emissions at 0520 UTC on 8 August. Continuing emissions were reported through 1120 UTC but were not identified in satellite imagery by 1720 UTC. KVERT showed ash plumes extended for about 300 km to the SW, SE, and NE.
2017 Aug 9	2017 Aug 12	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 2200 UTC extending S at 5.5 km altitude. KVERT and KBGS reported an ash emission at 0130 UTC on 10 August that extended SSW at 6.1 km altitude. Emissions were continuing at 1720 UTC. KGBS reported an ash emission at 2000 UTC extending SSW at 7.9 km altitude. Emissions were continuing at 1120 UTC on 11 August and possibly continuing through 2320 UTC. A new ash emission was reported by KBGS at 2330 UTC extending SW at 6.7 km altitude that was obscured by meteoric clouds. Emissions continued at 0400 UTC on 12 August at 7.9 km altitude. The Anchorage VAAC reported residual emissions from this event at 0447 UTC. Ash was no longer identifiable at 1036 UTC. Emissions continued at 6.7 km altitude at 1120 UTC but were no longer identificable at 1720 UTC. KVERT showed ash plumes extended for about 300 km to the SW, SE, and NE.
2017 Aug 15	2017 Aug 23	Ash Plume	Based on HIMAWARI-8 information, the Tokyo VAAC observed a possible ash emission at 1500 UTC extending N at 6.1 km altitude. Emissions were continuing at 1720 UTC. KBGS confirmed an ash emission at 1929 UTC extending NW at 6.7 km altitude. Emissions were continuing at 2320 UTC. KVERT and KBGS reported a new ash emission at 0535 UTC on 16 August that extended NW at 7.0 km altitude. Emissions were continuing at both 6.1 and 7.0 km altitude at 1720 UTC on 18 August. KVERT and KBGS reported a new ash emission at 2030 UTC extending NW at 7.0 km altitude. Emissions were continuing at 2320 UTC on 19 August extending NW at 7.0 km altitude. A new ash emission was reported by KBGS at 0004 UTC on 20 August that extended NW at 7.9 km altitude. Ash emissions were continuing at 2320 UTC at both 7.0 and 7.9 km altitude but were no longer identifiable at 7.0 km altitude by 0520 UTC on 21 August. Ash emissions were continuing at 1720 on 22 August at 7.9 km altitude but were no longer identifiable at 0520 on 23 August. KVERT showed that ash plumes extended for about 315 km to the E and NW.
2017 Aug 23	2017 Aug 26 (in or before)	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1500 UTC extending W at 6.7 km altitude. KVERT confirmed continuing emissions at 2320 UTC. Emissions were continuing at 1720 UTC on 25 August, but were no longer identifiable in satellite imagery by 0520 on 26 August. KVERT reported that ash plumes extended for about 550 km in multiple directions.
2017 Aug 30	- - - -	Ash Plume	Based on HIMAWARI-8 satellite imagery, the Tokyo VAAC observed a possible ash emission at 0730 UTC extending NE at 5.5 km altitude. Emissions were continuing at 1120 UTC but were no longer identifiable in satellite imagery by 1720 UTC.
2017 Sep 2	2017 Sep 3	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 2000 UTC extending SW at 5.8 km altitude. Continuing ash emissions were observed at 0520 UTC on 3 August, but were not identifiable in satellite imagery by 1120 UTC.
2017 Sep 7	2017 Sep 8	Ash Plume	Based on HIMAWARI-8 satellite, KVERT, and KBGS information, the Tokyo VAAC reported an ash emission at 2146 UTC extending NE at 7.0 km altitude that was not identifiable in satellite imagery. At 2158 UTC, UHPP reported the ash emission in satellite imagery extending W at ?7.0 km altitude. Emissions were continuing at 0220 UTC on 8 September, but ash had disspated by 0520 UTC. Satellite data by KVERT showed an ash plume extended for about 50 km NE.
2017 Sep 8	2017 Sep 17	Thermal Anomaly	Satellite data by KVERT showed an intermittent weak thermal anomaly.
2017 Sep 13	- - - -	Ash Plume	Based on HIMAWARI-8 satellite and UHPP information, the Tokyo VAAC reported an ash emission at 0005 UTC extending SE at 7.0 km altitude that was not identifiable in satellite imagery.
2017 Sep 18	- - - -	Ash Plume	Based on HIMAWARI-8 satellite and KVERT information, the Tokyo VAAC reported an ash emission at 1748 UTC extending E at 5.2 km altitude that was not identifiable in satellite imagery.

Episode 3 | Eruption

Summit crater

2017 Dec 5 - 2018 Jul 14

Evidence from Observations: Reported

List of 52 Events for Episode 3 at Summit crater

Start Date	End Date	Event Type	Event Remarks
2017 Dec 4	2017 Dec 6	Ash Plume	Based on HIMAWARI-8 satellite and KBGS information, the Tokyo VAAC reported an ash emission at 2125 UTC extending ENE at 6.1 km altitude. Continuing emissions were reported through 1720 UTC on 5 December, dropping to 5.2 km altitude or lower by 2320 UTC. Emissions were no longer identifiable in satellite imagery by 1130 UTC on 6 December. KVERT reported ash plumes extended for about 180 km.
2017 Dec 5	2018 Jan 8	Thermal Anomaly	KVERT reported intermittent weak thermal anomalies over the volcano.
2017 Dec 6	2017 Dec 7	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC reported a possible ash emission at 1220 UTC extending E at 5.2 km altitude. Continuing emissions were reported through 1120 UTC on 7 December, and had dissipated in satellite imagery by 1720 UTC. KVERT reported ash plumes extended for about 180 km.
2017 Dec 7	- - - -	Ash Plume	Based on HIMAWARI-8 satellite, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 2211 UTC extending ESE at 4.3 km altitude that was not identifiable in satellite imagery. KVERT reported that ash extended for about 95 km to the E.
2017 Dec 14	2017 Dec 15	Ash Plume	Based on HIMAWARI-8 satellite and UHPP information, the Tokyo VAAC reported an ash emission at 2101 UTC extending NW at 6.1 km altitude. An ash emission was reported at 2241 UTC extending NE at 6.4 km altitude. Another ash emission was reported at 0422 on 15 December extending NW at 5.2 km altitude. None were visible in satellite imagery.
2017 Dec 16	- - - -	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 1110 UTC extending E at 5.2 km altitude. Continuing emissions were observed at 1720 UTC. KVERT confirmed a new ash emission at 2130 UTC extending NE at 6.1 km altitude. Ash was no longer identifiable by 2330 UTC. KVERT reported that ash extended for about 140 km E.
2017 Dec 18	2017 Dec 19	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 2000 UTC extending N at 5.5 km altitude. KBGS reported an ash emission at 2100 UTC extending NNW at 6.1 km altitude. KVERT reported an ash emission at 0010 UTC on 19 December extending NE at 6.4 km altitude. Emissions were continuing at 1720 UTC but were no longer identifiable by 2320 UTC. KVERT reported that ash extended for about 140 km to the E.
2017 Dec 21	- - - -	Ash Plume	Based on HIMAWARI-8 satellite, KVERT, and UHPP information, the Tokyo VAAC reported an ash emission at 0416 UTC extending E at 7.3 km altitude that was not identifiable in satellite imagery. KVERT reported that gas-steam plumes containing ash extended for about 220 km E.
2017 Dec 23	2017 Dec 24	Ash Plume	Based on HIMAWARI-8 satellite information, the Tokyo VAAC observed a possible ash emission at 2300 UTC extending E at 5.2 km altitude. KVERT confirmed continuing emissions at 0520 on 24 December. Ash was no longer identifiable in satellite imagery by 1120 UTC. KVERT reported that gas-steam plumes containing ash extended for about 220 km E.
2018 Jan 3	2018 Jan 5	Ash Plume	Based on HIMAWARI-8, UHPP, KVERT, and KBGS information, at 0030 UTC the Tokyo VAAC reported an eruption at 0030 UTC extending SE at 6.1 km altitude. At 0520 UTC and 1120 UTC ash emissions were continuing, moving E at 6.1 km altitude. At 1720 UTC ash emissions were continuing, moving NE at 6.1 km altitude. At 2320 UTC ash emissions were continuing, moving SW at 6.1 km altitude. At 0520 UTC on 4 January ash emissions were continuing, moving W at 6.1 km altitude. At 1120 UTC ash was continuously observed on satellite imagery moving NW at 6.1 km altitude. At 1710 UTC ash extended NW at 6.1 km altitude. By 2320 UTC ash had dissipated. Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 150 km in multiple directions.
2018 Jan 5	- - - -	Ash Plume	Based on HIMAWARI-8, and KVERT information, at 1710 UTC on 4 January, the Tokyo VAAC reported a possible eruption observed at 1620 UTC extending NW at 5.5 km altitude. At 2320 UTC emissions were continuing, moving NW at 5.5 km altitude. At 0530 UTC on 5 January ash was reported extending WNW at 6.1 km altitude. By 1120 UTC ash was no longer identifiable on satellite imagery.
2018 Jan 6	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 2030 UTC on 5 January, the Tokyo VAAC reported a possible eruption observed at 1950 UTC extending W at 5.2 km altitude. At 2320 UTC emissions were continuing, moving NW at 5.2 km altitude. Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 160 km NW.
2018 Jan 6	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, at 0030 UTC, the Tokyo VAAC noted that an eruption was reported at 0035 UTC extending SW at 6.7 km altitude.
2018 Jan 6	2018 Jan 10	Ash Plume	Based on HIMAWARI-8 and KVERT information, at 0130 UTC the Tokyo VAAC noted an eruption reported at 0133 UTC extending SW at 7.0 km altitude. At 0520 UTC, 1120 UTC, and 1720 UTC emissions were continuing, extending NW at 7.0 km altitude. At 2320 UTC emissions were continuing moving N at 7.0 km altitude. At 0520 UTC on 7 January emissions were continuing, moving E at 7.0 km altitude. At 1120 UTC emissions were continuing, moving NE at 7.0 km altitude. At 1720 UTC and 2320 UTC emissions were continuing, moving N at 7.0 km altitude. At 0520 UTC and 1120 UTC on 8 January emissions were continuing, moving N at 6.7 km altitude. At 1720 UTC and 2320 UTC emissions were continuing, moving NW at 6.7 km altitude. At 0520 UTC on 9 January emissions were continuing, moving NW at 6.7 km altitude. At 1120 UTC emissions were continuing, moving NW at 6.1 km altitude. At 1720 UTC emissions were continuing, moving NE at 6.1 km altitude. At 2320 UTC emissions were continuing, moving E at 6.1 km altitude. At 0520 UTC on 10 January emissions were continuing, moving E at 6.1 km altitude. By 1130 UTC, ash was no longer identifiable in satellite imagery. Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 160 km E.
2018 Jan 12	- - - -	Ash Plume	Based on satellite observations KVERT reported that gas-and-steam plumes containing some ash drifted about 120 km W.
2018 Jan 18	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 1720 UTC on 17 January, the Tokyo VAAC reported a possible eruption observed at 1600 UTC extending N at 5.5 km altitude. At 2320 UTC emission were continuing, moving SE at 5.5 km altitude. Based on satellite observations KVERT reported that gas-and-steam plumes containing some ash drifted about 120 km W and E.
2018 Jan 18	- - - -	Ash Plume	Based on HIMAWARI-8, KBGS, and KVERT information, at 0240 UTC, the Tokyo VAAC noted an eruption was reported at 0240 UTC extending SW at 6.1 km altitude. At 0520 UTC ash emissions were continuing, extending SW at 6.1 km altitude. By 1120 UTC ash was not identifiable on satellite imagery.
2018 Feb 17	- - - -	Ash Plume	Based on HIMAWARI-8 and UHPP information, at 2110 UTC on 17 February, the Tokyo VAAC noted that ash was reported at 2044 UTC extending SW at 5.2 km altitude. Ash was not identifiable from satellite data.
2018 Apr 23	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 0740 UTC, the Tokyo VAAC reported a possible eruption at 0720 UTC extending SW at 5.5 km altitude. By 1130 UTC ash had dissipated on satellite imagery.
2018 Apr 24	- - - -	Ash Plume	Based on HIMAWARI-8 and UHPP information, at 0340 UTC, the Tokyo VAAC noted that ash was reported at 0349 UTC extending S at 5.2 km altitude. Ash was not identifiable in satellite imagery.
2018 Apr 25	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, at 2200 UTC on 24 April, the Tokyo VAAC noted that an eruption was reported at 2200 UTC extending SE at 5.2 km altitude. Ash was not identifiable in satellite data. According to visual data by KVERT volcanologists, gas-steam plumes contained some amount of ash.
2018 Apr 30	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 1620 UTC on 29 April the Tokyo VAAC reported a possible eruption observed at 1510 UTC extending SE at 5.5 km altitude. At 1720 UTC ash was continuously observed in satellite imagery extending SE at 5.5 km altitude. By 2320 UTC ash had dissipated on satellite imagery.
2018 Apr 30	2018 May 1	Ash Plume	Based on HIMAWARI-8 information, at 1100 UTC, the Tokyo VAAC reported a possible eruption observed at 1000 UTC extending NE at 5.2 km altitude. At 1420 UTC and 1720 UTC ash was continuously observed in satellite imagery moving NE at 5.2 km altitude. By 2320 UTC ash had dissipated on satellite imagery.
2018 May 2	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, at 0450 UTC the Tokyo VAAC noted an eruption with was reported at 0456 UTC, with an ash plume extending SE at 5.2 km altitude. Ash was not identifiable in satellite data.
2018 May 4	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 0800 UTC, the Tokyo VAAC reported a possible eruption observed at 0640 UTC with ash extending SE at 5.2 km altitude. By 1120 UTC ash had dissipated on satellite imagery.
2018 May 5	2018 May 6	Ash Plume	Based on HIMAWARI-8 information, at 1220 UTC on 5 May, the Tokyo VAAC reported a possible eruption observed at 1140 UTC with ash extending SE at 5.2 km altitude. By 1720 UTC ash had dissipated on satellite imagery
2018 May 8	- - - -	Ash Plume	Based on HIMAWARI-8 and KVERT information, at 2350 UTC on 7 May the Tokyo VAAC reported a possible eruption observed at 2300 UTC with ash extending S at 5.2 km altitude. At 0020 UTC on 8 May an eruption was reported at 2350 UTC with ash that extended SSE at 5.5 km altitude. At 0520 UTC possible ash emissions were continuing, moving S at 5.5 km altitude. At 0730 UTC ash was continuously observed in satellite imagery moving S at 5.5 km altitude. At 0847 UTC the Anchorage VAAC reported that the ash signal still persisted in satellite imagery moving S at 5.5 km altitlude. At 1412 UTC the ash was not identifiable in satellite imagery. Based on webcam and satellite observations KVERT reported that ash extended for about 340 km to the SE.
2018 May 10	- - - -	Ash Plume	Based on HIMAWARI-8 and KVERT information, at 0020 UTC the Tokyo VAAC reported a possible eruption observed at 0000 UTC with ash extending SE at 5.2 km altitude. An eruption was reported at 0050 UTC with ash extending SE at 5.5 km altitude. By 0520 UTC ash had dissipated on satellite imagery.
2018 May 10	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 0720 UTC the Tokyo VAAC reported a possible eruption observed at 0650 UTC with ash extending SE at 5.5 km altitude. At 1120 UTC ash was continuously observed in satellite imagery moving SE at 5.5 km altitude. By 1720 UTC ash had dissipated on satellite imagery. Based on webcam and satellite observations KVERT reported that ash extended for about 340 km to the SE.
2018 May 11	- - - -	Ash Plume	Based on HIMAWARI-8 and UHPP information, at 2110 UTC on 10 May the Tokyo VAAC reported that ash was observed at 1850 UTC extending SE at 4.6 km altitude. Ash was not identifiable in satellite imagery.
2018 May 11	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, at 0330 UTC the Tokyo VAAC noted a report of an eruption with ash at 0300 UTC extending SE at 6.1 km altitude. At 0520 UTC ash was continuously observed in satellite imagery moving SE at 6.1 km altitude. By 1120 UTC ash was not identifiable in satellite imagery.
2018 May 13	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 1930 UTC on 12 May the Tokyo VAAC reported a possible eruption observed at 1900 UTC with ash extending SW at 5.5 km altitude. At 2320 UTC ash was continuously observed in satellite imagery moving SW at 5.5 km altitude. By 0520 UTC on 13 May ash had dissipated on satellite imagery.
2018 May 13	2018 May 15	Thermal Anomaly	KVERT reported that a thermal anomaly over the volcano was noted.
2018 May 13	2018 May 14	Ash Plume	Based on HIMAWARI-8 information, at 0920 UTC the Tokyo VAAC reported a possible eruption observed at 0900 UTC with ash extending SW at 4.9 km altitude. At 1120 UTC ash was continuously observed in satellite imagery. By 1720 UTC ash had dissipated in satellite imagery.
2018 May 14	- - - -	Ash Plume	Based on HIMAWARI-8 and UHPP information, at 0140 UTC on 14 May the Tokyo VAAC reported a possible eruption observed at 0120 UTC with ash extending SW at 7.3 km altitude. At 0520 UTC ash was continuously observed in satellite imagery moving NW at 7.3 km altitude. At 0730 UTC ash extended N at 7.3 km altitude. By 1120 UTC ash at 7.3 km altitude had dissipated in satellite imagery.
2018 May 14	2018 May 15	Ash Plume	Based on HIMAWARI-8 information, at 0730 UTC the Tokyo VAAC reported a possible eruption observed at 0620 UTC with ash extending NE at 6.1 km altitude. At 1120 UTC ash was continuously observed in satellite imagery moving NE at 6.1 km altitude. By 1550 UTC ash at 6.1 km altitude had dissipated.
2018 May 15	- - - -	Explosion	Strong explosions began at 0315, and generated ash plumes that rose as high as 10.5 km. The ash clouds lingered around Klyuchevskoy and surrounding volcanoes for about eight hours before gradually dissipating.
2018 May 15	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, at 1550 UTC on 14 May the Tokyo VAAC reported a possible eruption observed at 1530 UTC with ash extending NE at 9.5 km altitude. At 1720 UTC and 2020 UTC ash was continuously observed in satellite imagery moving E at 9.5 km altitude. By 2210 UTC ash had dissipated in satellite imagery.
2018 May 15	- - - -	Avalanche	KVERT reported that a hot avalanche and incandescence of the volcanic summit at night were noted.
2018 May 15	- - - -	Ash Plume	Based on HIMAWARI-8 and KBGS information, at 2210 UTC on 14 May the Tokyo VAAC noted an eruption reported at 2201 UTC with ash extending NE at 10.1 km altitude. At 2240 UTC ash was moving NE at 10.1 km altitude. By 0220 UTC on 15 May, ash had dissipated in satellite imagery.
2018 May 15	- - - -	VEI (Explosivity Index)	VEI 3
2018 May 19	2018 May 20	Thermal Anomaly	KVERT reported that a thermal anomaly over the volcano was noted.
2018 May 24	2018 May 25	Thermal Anomaly	KVERT reported that a thermal anomaly over the volcano was noted.
2018 May 26	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 2140 UTC on 25 May the Tokyo VAAC reported a possible eruption observed at 2040 UTC with ash extending E at 5.5 km altitude. By 2320 UTC ash was not identifiable in satellite imagery.
2018 May 28	- - - -	Thermal Anomaly	KVERT reported that a thermal anomaly over the volcano was noted.
2018 Jun 6	2018 Jun 7	Ash Plume	Based on HIMAWARI-8 information, at 1220 UTC on 6 June the Tokyo VAAC reported a possible eruption observed at 1130 UTC with ash extending W at 5.5 km altitude. At 1720 UTC ash emissions were continuing, moving SW at 5.5 km altitude. By 2320 UTC ash had dissipated on satellite imagery.
2018 Jun 16	- - - -	Ash Plume	Based on HIMAWARI-8, KVERT, and UHPP information, at 2200 UTC on 15 June the Tokyo VAAC noted an ash eruption reported at 2138 UTC with ash extending SW at 6.1 km altitude. Ash was not identifiable in satellite imagery.
2018 Jul 14	- - - -	Ash Plume	Based on HIMAWARI-8, and KBGS information, at 0400 UTC the Tokyo VAAC noted and eruption reported at 0102 UTC with ash extending SW at 6.1 km altitude. Ash was not identifiable in satellite imagery.
2018 Sep 16	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 0630 UTC the Tokyo VAAC reported re-suspended ash moving E at 5.2 km altitude. It had dissipated by 1720 UTC.
2018 Nov 5	2018 Nov 6	Ash Plume	Based on HIMAWARI-8 information, at 0810 UTC the Tokyo VAAC reported re-suspended ash moving SE at 4.9 km altitude. It was still present at 1120 UTC and 1720 UTC. It had dissipated by 2320 UTC.
2018 Nov 8	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 2310 UTC on 7 November the Tokyo VAAC reported re-suspended ash moving SE at 4.9 km altitude. It was still present at 0220 UTC, 0520 UTC, and 1120 UTC on 8 November, and it had dissipated by 1720 UTC.
2018 Nov 9	- - - -	Ash Plume	Based on HIMAWARI-8 information, at 0630 UTC the Tokyo VAAC reported re-suspended ash moving E at 3.0 km altitude. It was still present at 1120 UTC, and it had dissipated by 1720 UTC.

2015 Jan 1 - 2015 May 10 Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit crater and multiple flanks

2015 Jan 1 - 2015 May 10

Evidence from Observations: Reported

List of 61 Events for Episode 1 at Summit crater and multiple flanks

Start Date	End Date	Event Type	Event Remarks
2014 Dec 19	2014 Dec 31	Seismicity (volcanic)	Based on seismic data from KB GS RAS, KVERT reported that seismic activity at Klyuchevskoy began to increase during 19-20 December and then increased again on 31 December.
2015 Jan 1	- - - -	Incandescent ejecta	KVERT reported that a Strombolian eruption began; bombs were ejected 300-400 m above the crater.
2015 Jan 1	- - - -	Bombs	KVERT reported that a Strombolian eruption began; bombs were ejected 300-400 m above the crater.
2015 Jan 1	- - - -	Thermal Anomaly	A thermal anomaly was detected in satellite images, possibly indicating that a Strombolian eruption had begun.
2015 Jan 4	2015 Feb 26	Thermal Anomaly	Multiple near-daily MODVOLC thermal alerts were issued.
2015 Jan 9	2015 Jan 30	Ash Plume	Explosions generated ash plumes that rose to altitudes of 6-7 km. Satellite images showed ash plumes drifting 160 km SW and NE during 9-16 January.
2015 Jan 9	2015 Mar 6	Incandescent ejecta	Strombolian and Vulcanian activity continued.
2015 Jan 9	2015 Jan 23	Lava flow	A lava flow effused onto the SE flank.
2015 Jan 9	2015 Feb 13	Bombs	Bombs were ejected 200-300 m above the crater.
2015 Jan 9	2015 Feb 27	Incandescence	Incandescence at the summit was visible.
2015 Jan 10	- - - -	Ash Plume	Strong gas-and-steam emissions containing ash were recorded by the webcam.
2015 Jan 10	- - - -	Lava flow	Video images indicated a possible lava flow on the S flank.
2015 Jan 11	2015 Jan 30	Explosion	Explosions generated ash plumes that rose to altitudes of 6-7 km.
2015 Jan 11	- - - -	Ash Plume	Satellite images showed a 12.5-km-wide, 36.8-km-long ash plume drifting at an altitude of 5 km.
2015 Jan 11	- - - -	Ashfall	Ashfall was reported in Kozyrevsk Village (50 km W).
2015 Jan 12	- - - -	Ash Plume	An ash plume rose to an altitude of 5.5 km and drifted 35 km.
2015 Jan 16	2015 Jan 23	Ash Plume	Ash plumes drifting 210 km SW, NW, and NE at altitudes of 5-6 km.
2015 Jan 16	2015 Feb 27	Thermal Anomaly	Satellite images showed a daily, big, bright thermal anomaly over the volcano.
2015 Jan 21	- - - -	Ashfall	Ashfall was reported in Klyuchi Village (30 km NNE).
2015 Jan 23	2015 Jan 30	Ash Plume	Satellite images showed ash-and-gas plumes drifting 300 km W, N, NE, E, and SE at altitudes of 5.5-7 km.
2015 Jan 23	2015 Feb 20	Lava flow	A lava flow effused onto the E flank.
2015 Jan 27	2015 Jan 28	Explosion	Phreatic explosions at the lava flow front produced gas-and-steam clouds with minor amounts of ash that rose to altitudes of 7-8 km.
2015 Jan 27	2015 Jan 28	Phreatic activity	Phreatic explosions at the lava flow front produced gas-and-steam clouds with minor amounts of ash that rose to altitudes of 7-8 km.
2015 Jan 27	2015 Jan 28	Ashfall	Ashfall was reported in Klyuchi Village (30 km NNE) and near the Khapitsa River on 27 January, and in Kozyrevsk Village (50 km W) on 28 January.
2015 Jan 30	2015 Feb 6	Explosion	Explosions generated ash plumes that rose to altitudes of 5-6 km.
2015 Jan 30	2015 Feb 6	Ash Plume	Satellite images showed ash-and-gas plumes drifting in multiple directions at altitudes of 5.5-6 km.
2015 Feb 4	2015 Feb 5	Ash Plume	Ash plumes drifted about 1,000 km NW and N.
2015 Feb 5	- - - -	Ashfall	Ashfall was reported in Klyuchi Village (30 km NNE).
2015 Feb 6	2015 Feb 13	Explosion	Explosions generated ash plumes that rose to altitudes of 5.5-6.5 km.
2015 Feb 6	2015 Feb 13	Ash Plume	Satellite images showed ash plumes drifting about 400 km mainly NW and N at altitudes of 5.5-6.5 km.
2015 Feb 7	- - - -	Ashfall	Ashfall was reported in Kozyrevsk Village (50 km W).
2015 Feb 11	- - - -	Ashfall	Ashfall was reported in Klyuchi Village (30 km NNE) on 11 February.
2015 Feb 13	2015 Feb 20	Explosion	Explosions generated ash plumes that rose to altitudes of 5-8 km.
2015 Feb 13	2015 Feb 20	Ash Plume	Explosions generated ash plumes that rose to altitudes of 5-8 km. Satellite images showed that ash plumes drifted about 600 km mainly E, SE, and S.
2015 Feb 13	2015 Feb 16	Ashfall	Ashfall was reported in Klyuchi Village (30 km NNE).
2015 Feb 13	2015 Feb 27	Bombs	Bombs were ejected 150 m above the crater.
2015 Feb 15	- - - -	Ash Plume	At 1035 the webcam recorded ash plumes rising to altitudes of 6-6.5 km and drifting 74 km E. At 1211, 1347, and 1524 ash plumes rose to an altitude of 8 km and drifted 110-232 km E and ESE. At 1656 ash plumes rose to altitudes of 7.5-7.8 km and drifted 232 km ESE.
2015 Feb 15	- - - -	VEI (Explosivity Index)	VEI 2
2015 Feb 16	- - - -	Ash Plume	At 1512 ash plumes identified in satellite images rose to an altitude of 6 km and drifted 270 km S.
2015 Feb 17	- - - -	Ash Plume	At 0641, 1503, and 1505, ash plumes rose to an altitude of 5.5 km and drifted 114-240 km SE.
2015 Feb 20	2015 Mar 6	Explosion	Explosions generated ash plumes that rose to altitudes of 5-6 km.
2015 Feb 20	2015 Mar 6	Ash Plume	Explosions generated ash plumes that rose to altitudes of 5-6 km. Satellite images showed ash plumes that drifted up to 430 km mainly NE, E, and SE.
2015 Feb 27	2015 Mar 6	Thermal Anomaly	Satellite images showed a daily thermal anomaly over the volcano.
2015 Mar 9	- - - -	Seismicity (volcanic)	The magnitude of seismic tremor significantly decreased at 0520, likely signifying the end of the explosive eruption.
2015 Mar 10	- - - -	Seismicity (volcanic)	After a quiet period of 24 hours, volcanic-tremor magnitude significantly increased at 0500.
2015 Mar 10	- - - -	Ash Plume	Satellite images detected a gas-and-steam plume with small amounts of ash drifting about 92 km ESE at an altitude of 5 km.
2015 Mar 10	2015 Mar 11	Thermal Anomaly	A weak thermal anomaly over the summit was detected.
2015 Mar 13	2015 Mar 20	Explosion	Explosions generated ash plumes that rose to altitudes of 5-5.5 km.
2015 Mar 13	2015 Mar 20	Ash Plume	Explosions generated ash plumes that rose to altitudes of 5-5.5 km. During 16-17 March satellite images showed ash plumes that drifted 90 km E. Ash plumes were again detected in images during 22-23 March.
2015 Mar 16	2015 Mar 17	Thermal Anomaly	Satellite images showed a weak thermal anomaly over the volcano.
2015 Apr 13	2015 Mar 14	Incandescence	Incandescence at the summit was indicative of renewed Strombolian activity.
2015 Apr 13	2015 Apr 14	Degassing	KVERT reported that gas-and-steam emissions increased at 0840 on 13 April and continued at least through 1215 on 14 April.
2015 Apr 16	2015 Apr 23	Thermal Anomaly	Satellite images detected a weak thermal anomaly over the volcano during 16-17 and 23 April.
2015 Apr 16	2015 Apr 23	Degassing	KVERT reported that moderate gas-and-steam activity was recorded by the webcam during 16-17, 19, 21, and 23 April.
2015 Apr 18	- - - -	Ash Plume	A webcam recorded a narrow ash plume that rose 1-2 km and drifted 100 km SE.
2015 Apr 18	- - - -	Incandescent ejecta	KVERT reported that Strombolian activity continued.
2015 Apr 21	- - - -	Ash Plume	A gas plume containing a small amount of ash drifted 147 km E.
2015 May 1	2015 May 10	Thermal Anomaly	A thermal anomaly was observed.
2015 May 2	2015 May 5	Ash Plume	Gas-and-steam plumes containing ash drifted over 450 km SE.
2015 May 2	2015 May 5	Thermal Anomaly	Satellite images detected a daily weak thermal anomaly over the volcano.
2015 May 9	2015 May 10	Ash Plume	Satellite data showed: gas-steam plumes containing small amount of ash drifted 100 km to the east of the volcano.

2013 Aug 15 - 2013 Dec 20 Confirmed Eruption VEI: 3

Episode 1 | Eruption

Summit crater and multiple flanks

2013 Aug 15 - 2013 Dec 20

Evidence from Observations: Reported

List of 59 Events for Episode 1 at Summit crater and multiple flanks

Start Date	End Date	Event Type	Event Remarks
2013 Aug 15	2013 Sep 27	Ash Plume	Video images recorded incandescence from the crater, and gas-and-steam plumes containing minor amounts of ash rising as high as 6 km and drifting NE.
2013 Aug 15	2013 Nov 29	Incandescent ejecta	Based on seismic data from the Kamchatka Branch of Geophysical Services (KBGS; Russian Academy of Sciences), KVERT reported that a Strombolian eruption began at 1830, and continued to be reported each week.
2013 Aug 15	2013 Aug 16	Thermal Anomaly	Satellite images detected a large, bright thermal anomaly on 15-16 August.
2013 Aug 15	2013 Oct 21	Thermal Anomaly	Multiple and tens of near-daily MODVOLC thermal alerts were issued.
2013 Aug 16	2013 Sep 27	Thermal Anomaly	A large thermal anomaly from the lava dome was detected in satellite images.
2013 Aug 26	- - - -	Lava flow	A lava flow effused onto the SW flank, producing a thermal anomaly detected in satellite images.
2013 Sep 14	2013 Dec 27	Lava flow	On 14 September, KVERT noted four lava flows on the NW, W, and SW flanks. Ongoing flow activity was reported through 30 October. Satellite images continued to detect thermal anomalies over the summit and the lava flow on the SW flank as late as 27 December that were attributed to cooling flows.
2013 Oct 1	- - - -	Ash Plume	Satellite data showed an ash plume extending about 100 km to the ESE.
2013 Oct 6	- - - -	Seismicity (tremor)	A sharp increase of tremor occurred.
2013 Oct 6 ± 3 days	- - - -	Explosion	According to video data, a flank eruption around this time began at the pass between Kliuchevskoi and Kamen volcanoes (Kamen's summit is only 5 km SW of Kliuchevskoi's).
2013 Oct 6 ± 3 days	- - - -	Ash Plume	Local incandescence and gas-and-steam plumes were observed from the pass, and video data showed incandescence at Kliuchevskoi's summit and the W flank at night, and gas-and-steam plumes containing ash.
2013 Oct 6 ± 3 days	- - - -	Incandescent ejecta	Strombolian activity continued and several lava flows traveled down the NW, W, SW flanks.
2013 Oct 6 ± 3 days	- - - -	Lava flow	Strombolian activity continued and several lava flows traveled down the NW, W, SW flanks.
2013 Oct 6 ± 3 days	- - - -	Incandescence	Local incandescence and gas-and-steam plumes were observed from the pass, and video data showed incandescence at Kliuchevskoi's summit and the W flank at night, and gas-and-steam plumes containing ash.
2013 Oct 9	2013 Oct 10	Ash Plume	Ash plumes rose to an altitude of 6 km and minor ashfall was noted at Klyuchi Village.
2013 Oct 9	2013 Oct 10	Ashfall	Ash plumes rose to an altitude of 6 km and minor ashfall was noted at Klyuchi Village.
2013 Oct 11	- - - -	Explosion	KVERT reported that a strong explosion from a new cinder cone low on Kliuchevskoi’s SW flank occurred between 2020 and 2030.
2013 Oct 11	- - - -	Ash Plume	An ash plume rose to altitudes of 6-7 km and drifted E.
2013 Oct 11	- - - -	Cinder Cone	KVERT reported that a strong explosion from a new cinder cone low on Kliuchevskoi’s SW flank occurred between 2020 and 2030.
2013 Oct 15	2013 Oct 16	Explosion	Video data showed strong Vulcanian explosive activity.
2013 Oct 15	- - - -	Phreatic activity	Phreatic explosions on the SW flank generated ash plumes that rose 3-4 km.
2013 Oct 15	- - - -	Ash Plume	Ash plumes rose to altitudes of 7-8 km and drifted 140 km SSW. Phreatic explosions on the SW flank generated ash plumes that rose 3-4 km. Satellite images showed an ash plume rising to an altitude of 7.5 km at 1419 and drifting 103 km SSW. Activity increased again; ash plumes rose to altitudes of 9 km at 1655 and 10 km afterwards. Ash plumes drifted SSW and S. That evening ash plumes rose 8 km and drifted ENE.
2013 Oct 15	- - - -	Ash Plume	Based on Satellite data KVERT, and KBGS information, the Tokyo VAAC reported ash emissions initially drifting SSW at 8.2 km altitude. Later in they day they reported emissions continuing and plumes reaching 10.1 km altitude.
2013 Oct 15	2013 Oct 16	Incandescent ejecta	Strombolian activity, several lava flows, and phreatic plumes continued.
2013 Oct 15	2013 Oct 16	Lava flow	Numerous lava flows on the SW flank and a probable flank eruption at the pass between Kliuchevskoi and Kamen volcanoes led to vigorous melting of Bogdanovich glacier; the resulting water increased the Studenaya River's flow, which then destroyed part of the road near Kozyrevsk village (about 50 km W).
2013 Oct 15	2013 Oct 16	Incandescence	Strong incandescence was observed at the summit and W flank at night.
2013 Oct 15	- - - -	VEI (Explosivity Index)	VEI 3
2013 Oct 16	- - - -	Ash Plume	At 0815 satellite images detected ash plumes that rose to altitudes of 2-3 km and drifted 480 km NNW. Seismic data indicated that ash plumes rose to an altitude of 10 km later in the morning. Clouds prevented direct observations but satellite images showed ash plumes drifting NW. At 1624 satellite images showed ash plumes drifting WSW at altitudes of 7-7.5 km.
2013 Oct 16	- - - -	Ash Plume	Based on Satellite data KVERT, and KBGS information, the Tokyo VAAC reported ash emissions drifting W at 10.1 km altitude and NW at 6.7 km altitude. Later in they day continuing emissions drifted E at 7.6 km altitude. The height of the ash was estimated by the seismic activity.
2013 Oct 16	- - - -	Ashfall	Minor ashfall was reported in Mayskoe Village.
2013 Oct 16	- - - -	VEI (Explosivity Index)	VEI 3
2013 Oct 18	2013 Oct 20	Seismicity (volcanic)	The eruption peaked and was characterized by high seismic activity, strong Vulcanian explosions, lava flows, intense incandescence, and ash plumes that rose to an altitude of 12 km and extended in various directions.
2013 Oct 18	2013 Oct 20	Explosion	The eruption peaked and was characterized by high seismic activity, strong Vulcanian explosions, lava flows, intense incandescence, and ash plumes that rose to an altitude of 12 km and extended in various directions.
2013 Oct 18	- - - -	Ash Plume	Based on Satellite data KVERT, and KBGS information, the Tokyo VAAC reported an eruption early in the day (17 October UTC) that produced an ash plume that drifted S at 10.1 km altitude. Three additional explosions were reported throughout the day that produced plumes that rose to 7.9 km and drifted S, 9.8 km and drifted E, and 9.1 km and drifted SE.
2013 Oct 18	2013 Oct 19	Ash Plume	Ash plumes rose to altitudes of 8-9 km and drifted 20-100 km SE. At 0559 on 19 October ash plumes observed in satellite images drifted 630 km SE at altitudes of 8-9 km. Ash plume altitudes fluctuated between 7-8 km later that day. A large amount of ash continued to drift 600 km SE.
2013 Oct 18	2013 Oct 20	Ash Plume	The eruption peaked and was characterized by high seismic activity, strong Vulcanian explosions, lava flows, intense incandescence, and ash plumes that rose to an altitude of 12 km and extended in various directions.
2013 Oct 18	2013 Oct 20	Incandescent ejecta	Strombolian activity continued with lava fragments ejected 500-800 m above the summit cinder cone.
2013 Oct 18	2013 Oct 20	Lava flow	The eruption peaked and was characterized by high seismic activity, strong Vulcanian explosions, lava flows, intense incandescence, and ash plumes that rose to an altitude of 12 km and extended in various directions.
2013 Oct 18	2013 Oct 20	Incandescence	The eruption peaked and was characterized by high seismic activity, strong Vulcanian explosions, lava flows, intense incandescence, and ash plumes that rose to an altitude of 12 km and extended in various directions.
2013 Oct 18	- - - -	VEI (Explosivity Index)	VEI 3
2013 Oct 19	- - - -	Ash Plume	Based on Satellite data KVERT, KBGS, and Petropavlovsk-Kamchatsky Airport (UHPP) information, the Tokyo VAAC reported continuing emissions observed at 9.1-9.8 km altitude drifting E and SE.
2013 Oct 19	- - - -	VEI (Explosivity Index)	VEI 3
2013 Oct 20	2013 Oct 24	Ash Plume	Based on Satellite data, KVERT, and KBGS information, the Tokyo VAAC reported continuing emissions and possible new emissions drifting E, S, and W at 5.2-8.2 km altitude.
2013 Oct 30	- - - -	Thermal Anomaly	Satellite remote sensing detected a thermal anomaly over the volcano caused by the continuation of the flank eruption.
2013 Nov 13	2013 Nov 15	Ash Plume	Based on Satellite data, the Tokyo VAAC reported possible new emissions each day drifting NE, at 5.2-6.4 km altitude.
2013 Nov 16	2013 Nov 17	Ash Plume	Based on Satellite and KBGS information, the Tokyo VAAC reported new and continuing emissions drifting at 6.4-8.2 km altitude.
2013 Nov 17	- - - -	Explosion	Video data showed a high-intensity explosion and Strombolian activity.
2013 Nov 17	- - - -	Ash Plume	KVERT reported that at 1235 an ash plume from Kliuchevskoi, detected in satellite images, rose to an altitude of 6.5 km and drifted 160 km NE. At 1322 an ash plume rose to an altitude of 7 km and drifted 130 km NE.
2013 Nov 19	- - - -	Explosion	At 1416 seismicity indicated a strong explosion, and observers reported that ash plumes rose to altitudes of 10-12 km and drifted SE.
2013 Nov 19	- - - -	Ash Plume	At 1416 seismicity indicated a strong explosion, and observers reported that ash plumes rose to altitudes of 10-12 km and drifted SE. Later that day the altitudes of the ash plumes were lower; video images showed ash plumes rising to altitudes of 5-5.5 km and drifting NE.
2013 Nov 19	- - - -	Ash Plume	Based on Satellite data KVERT, KBGS, and Petropavlovsk-Kamchatsky Airport (UHPP) information, the Tokyo VAAC reported an eruption and continuing emissions with an ash plume observed at 12.2 km altitude drifting SE and NE. Later in the day, emissions were drifting E at 9.1 km altitude.
2013 Nov 19	- - - -	VEI (Explosivity Index)	VEI 3
2013 Nov 20	- - - -	Ash Plume	Based on Satellite data and KVERT information, the Tokyo VAAC reported continuing emissions with an ash plume observed at 9.1 km altitude drifting E.
2013 Nov 22	2013 Nov 29	Thermal Anomaly	Satellite images recorded a daily thermal anomaly on the volcano.
2013 Nov 25	- - - -	Ash Plume	Based on satellite information, the Tokyo VAAC reported a possible eruption observed at 0600 UTC, and continuing emissions with an ash plume observed at 6.1 km altitude drifting E.
2013 Nov 30	- - - -	Ash Plume	Based on satellite information, the Tokyo VAAC reported a possible eruption at 0000 UTC, with an ash plume observed at 5.2 km altitude drifting E.
2013 Dec 6	2013 Dec 13	Ash Plume	During this period video images showed ash plumes rising to altitudes of 5-6 km. Satellite images detected ash plumes that drifted 1,200 km E during 6-8 December, NW during 9-10 December, and E and SE during 10-11 December.
2013 Dec 6	2013 Dec 27	Thermal Anomaly	Satellite images detected a weak thermal anomaly over the summit and the SW flank.
2013 Dec 17	- - - -	Explosion	The last strong explosion was detected.

2012 Sep 1 (?) - 2013 Jan 28 ± 3 days Confirmed Eruption VEI: 1

Episode 1 | Eruption

Summit crater?

2012 Sep 1 (?) - 2013 Jan 28 ± 3 days

Evidence from Observations: Reported

List of 9 Events for Episode 1 at Summit crater?

Start Date	End Date	Event Type	Event Remarks
2012 Jun 21	2012 Oct 14	Seismicity (tremor)	Episodes of volcanic tremor were detected.
2012 Sep 1	2012 Oct 14	Thermal Anomaly	A weak thermal anomaly was detected in satellite imagery.
2012 Oct 13	2012 Oct 15	Incandescent ejecta	Strombolian activity was observed at night.
2012 Oct 13	- - - -	VEI (Explosivity Index)	VEI 1
2012 Oct 14	2012 Oct 15	Thermal Anomaly	A weak thermal anomaly was detected in satellite imagery.
2012 Nov 23	2012 Dec 21	Incandescent ejecta	KVERT reported that video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions.
2012 Nov 23	2012 Nov 26	Thermal Anomaly	A weak thermal anomaly was detected in satellite images.
2012 Dec 1	2012 Dec 18	Thermal Anomaly	A thermal anomaly was detected in satellite images during 1, 4-8, 10, 12-13,16, and 18 December.
2013 Jan 18	2013 Jan 25	Incandescent ejecta	KVERT reported that video footage and satellite imagery showed Strombolian explosions at Kliuchevskoi, along with crater incandescence and gas-and-steam emissions.

[ 2011 Nov 2 - 2011 Nov 2 ] Uncertain Eruption

Episode 1 | Eruption

2011 Nov 2 - 2011 Nov 2

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Ash
	- - - -	- - - -	VEI (Explosivity Index)

2011 Mar 30 - 2011 Jul 3 Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit crater?

2011 Mar 30 - 2011 Jul 3

Evidence from Observations: Reported

List of 6 Events for Episode 1 at Summit crater?

Start Date	End Date	Event Type	Event Remarks
2011 Mar 30	- - - -	Explosion	Based on analyses of satellite imagery, the Tokyo VAAC reported that a possible eruption from Kliuchevskoi produced a plume that rose to an altitude of 5.2 km and drifted E.
2011 Mar 30	- - - -	Ash Plume	Based on analyses of satellite imagery, the Tokyo VAAC reported that a possible eruption from Kliuchevskoi produced a plume that rose to an altitude of 5.2 km and drifted E. Subsequent images that day showed continuing ash emissions that later dissipated.
2011 May 29	- - - -	Ash Plume	KVERT reported that an ash plume rose to an altitude of 5 km and drifted SW.
2011 Jun 6	- - - -	Ash Plume	The Tokyo VAAC reported that a possible eruption detected in satellite imagery produced a plume that rose to an altitude of 6.1 km and drifted NE. The VAAC stated that the ash could have also originated at Bezymianny.
2011 Jul 3	- - - -	Ash Plume	Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that an eruption from Kliuchevskoi produced a plume that rose to an altitude of 7 km and drifted E.
2011 Jul 3	- - - -	VEI (Explosivity Index)	VEI 2

2009 Aug 1 (?) - 2010 Dec 20 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

2009 Aug 1 (?) - 2010 Dec 20 (?)

Evidence from Observations: Reported

List of 7 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	Before eruption.
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
2009 Aug 1 (?)	- - - -	VEI (Explosivity Index)
2010 Jan 18	- - - -	VEI (Explosivity Index)

2008 Oct 8 - 2009 Apr 16 (?) Confirmed Eruption VEI: 1

Episode 1 | Eruption

2008 Oct 8 - 2009 Apr 16 (?)

Evidence from Observations: Reported

List of 8 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Audible Sounds
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
2008 Oct 8	- - - -	VEI (Explosivity Index)

2007 Feb 15 - 2007 Jul 15 Confirmed Eruption VEI: 2

Episode 1 | Eruption

2007 Feb 15 - 2007 Jul 15

Evidence from Observations: Reported

List of 9 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Bombs
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Lahar or Mudflow
2007 Feb 15	- - - -	VEI (Explosivity Index)
2007 Apr 22	- - - -	VEI (Explosivity Index)
2007 May 27	- - - -	VEI (Explosivity Index)

2005 Jan 20 (in or before) - 2005 Apr 7 Confirmed Eruption VEI: 2

Episode 1 | Eruption

2005 Jan 20 (in or before) - 2005 Apr 7

Evidence from Observations: Reported

List of 9 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Bombs
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Lahar or Mudflow
2005 Jan 20 (in or before)	- - - -	VEI (Explosivity Index)
2005 Feb 12	- - - -	VEI (Explosivity Index)

2004 Sep 15 - 2004 Sep 15 Confirmed Eruption VEI: 1

Episode 1 | Eruption

2004 Sep 15 - 2004 Sep 15

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Ash	weak or small
2004 Sep 15	- - - -	VEI (Explosivity Index)

2002 Nov 24 - 2004 Apr 8 Confirmed Eruption VEI: 2

Episode 1 | Eruption

2002 Nov 24 - 2004 Apr 8

Evidence from Observations: Reported

List of 9 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	Before eruption.
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow	Uncertain
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Lahar or Mudflow
2002 Nov 24	- - - -	VEI (Explosivity Index)
2002 Dec 24	- - - -	VEI (Explosivity Index)

2002 Apr 9 - 2002 Jun 9 (in or before) Confirmed Eruption VEI: 2

Episode 1 | Eruption

2002 Apr 9 - 2002 Jun 9 (in or before)

Evidence from Observations: Reported

List of 6 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
2002 Apr 9	- - - -	VEI (Explosivity Index)

2000 Jul 28 - 2000 Sep 22 Confirmed Eruption VEI: 2

Episode 1 | Eruption

2000 Jul 28 - 2000 Sep 22

Evidence from Observations: Reported

List of 6 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	Before eruption.
- - - -	- - - -	Explosion
- - - -	- - - -	Eruption cloud
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
2000 Jul 28	- - - -	VEI (Explosivity Index)

2000 Feb 3 - 2000 Feb 8 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

2000 Feb 3 - 2000 Feb 8 (?)

Evidence from Observations: Reported

List of 7 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Eruption cloud
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
2000 Feb 3	- - - -	VEI (Explosivity Index)

1999 Feb 5 - 1999 Jul 12 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1999 Feb 5 - 1999 Jul 12

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
1999 Feb 5	- - - -	VEI (Explosivity Index)

1998 Jul 23 - 1998 Sep 2 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

1998 Jul 23 - 1998 Sep 2 (?)

Evidence from Observations: Reported

List of 8 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	After eruption.
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Earthquakes (undefined)	After.
1998 Jul 23	- - - -	VEI (Explosivity Index)
1998 Sep 2	- - - -	VEI (Explosivity Index)

1997 Sep 7 - 1997 Sep 26 Confirmed Eruption VEI: 1

Episode 1 | Eruption

1997 Sep 7 - 1997 Sep 26

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
1997 Sep 7	- - - -	VEI (Explosivity Index)

1996 Nov 14 - 1997 Mar 20 ± 12 days Confirmed Eruption VEI: 2

Episode 1 | Eruption

1996 Nov 14 - 1997 Mar 20 ± 12 days

Evidence from Observations: Reported

List of 6 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Earthquakes (undefined)
1996 Nov 14	- - - -	VEI (Explosivity Index)
1997 Jan 7	- - - -	VEI (Explosivity Index)

1994 Sep 8 - 1995 Jan 14 (in or after) Confirmed Eruption VEI: 3

Episode 1 | Eruption

1994 Sep 8 - 1995 Jan 14 (in or after)

Evidence from Observations: Reported

List of 13 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Eruption cloud
- - - -	- - - -	Pyroclastic flow
- - - -	- - - -	Lava fountains
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)	Before.
- - - -	- - - -	Lahar or Mudflow
- - - -	- - - -	Property Damage
1994 Sep 8	- - - -	VEI (Explosivity Index)
1994 Oct 1	- - - -	VEI (Explosivity Index)

1992 Sep 12 - 1993 Sep 12 ± 1 days Confirmed Eruption VEI: 2

Episode 1 | Eruption

1992 Sep 12 - 1993 Sep 12 ± 1 days

Evidence from Observations: Reported

List of 10 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Lava fountains
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Lahar or Mudflow
- - - -	- - - -	Property Damage
1992 Sep 12	- - - -	VEI (Explosivity Index)
1993 Mar 20	- - - -	VEI (Explosivity Index)

1992 Jan 25 - 1992 May 25 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

1992 Jan 25 - 1992 May 25 (?)

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
1992 Jan 25	- - - -	VEI (Explosivity Index)

1991 Apr 8 - 1991 Jun 24 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

1991 Apr 8 - 1991 Jun 24 (?)

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Eruption cloud
1991 Apr 8	- - - -	VEI (Explosivity Index)

1986 Nov 27 - 1990 Sep 16 ± 15 days Confirmed Eruption VEI: 4

Episode 1 | Eruption

Summit, SE, SW, NE and east flanks

1986 Nov 27 - 1990 Sep 16 ± 15 days

Evidence from Observations: Reported

List of 16 Events for Episode 1 at Summit, SE, SW, NE and east flanks

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Eruption cloud
- - - -	- - - -	Pyroclastic flow
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
- - - -	- - - -	Bombs
- - - -	- - - -	Lightning
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Deformation (inflation)
- - - -	- - - -	Deformation (deflation)
- - - -	- - - -	Crater	Summit.
- - - -	- - - -	Lahar or Mudflow
1986 Nov 27	- - - -	VEI (Explosivity Index)
1987 Feb 19	- - - -	VEI (Explosivity Index)
1990 Jan 30	- - - -	VEI (Explosivity Index)

1986 Jun 8 - 1986 Jul 11 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1986 Jun 8 - 1986 Jul 11

Evidence from Observations: Reported

List of 7 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	Before eruption.
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Seismicity (tremor)	After eruption.
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Lahar or Mudflow
1986 Jun 8	- - - -	VEI (Explosivity Index)

1985 Aug 16 - 1986 Jan 21 Confirmed Eruption VEI: 3 (?)

Episode 1 | Eruption

Summit and NW flank (3100 m)

1985 Aug 16 - 1986 Jan 21

Evidence from Observations: Reported

List of 11 Events for Episode 1 at Summit and NW flank (3100 m)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	Before eruption.
- - - -	- - - -	Explosion
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Eruption cloud
- - - -	- - - -	Lava fountains
- - - -	- - - -	Lava flow
- - - -	- - - -	Avalanche
- - - -	- - - -	Ash
- - - -	- - - -	Lahar or Mudflow
1985 Aug 16	- - - -	VEI (Explosivity Index)
1985 Dec 2	- - - -	VEI (Explosivity Index)

1984 Mar 10 - 1985 Jan 28 Confirmed Eruption VEI: 3

Episode 1 | Eruption

1984 Mar 10 - 1985 Jan 28

Evidence from Observations: Reported

List of 12 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)	Before eruption.
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Eruption cloud
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
- - - -	- - - -	Bombs
- - - -	- - - -	Lahar or Mudflow
1984 Mar 10	- - - -	VEI (Explosivity Index)
1984 Nov 13	- - - -	VEI (Explosivity Index)

1982 Oct 7 - 1983 Jun 27 Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit and east flank (2875 m)

1982 Oct 7 - 1983 Jun 27

Evidence from Observations: Reported

List of 12 Events for Episode 1 at Summit and east flank (2875 m)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Lava fountains
- - - -	- - - -	Lava flow	violent, strong, or large
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Lahar or Mudflow
1982 Oct 7	- - - -	VEI (Explosivity Index)
1983	- - - -	Fatalities
1983 Mar 8	- - - -	VEI (Explosivity Index)

1982 Mar 24 - 1982 May 2 Confirmed Eruption VEI: 1

Episode 1 | Eruption

1982 Mar 24 - 1982 May 2

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion	weak or small
- - - -	- - - -	Phreatic activity	Uncertain
- - - -	- - - -	Ash
- - - -	- - - -	Bombs
1982 Mar 24	- - - -	VEI (Explosivity Index)

[ 1981 Dec 21 ] Uncertain Eruption

Episode 1 \| Eruption
1981 Dec 21 - Unknown				Evidence from Unknown

1981 Jan 25 - 1981 Aug 4 (?) Confirmed Eruption VEI: 1

Episode 1 | Eruption

1981 Jan 25 - 1981 Aug 4 (?)

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Seismicity (tremor)	After eruption.
- - - -	- - - -	Explosion	weak or small
- - - -	- - - -	Ash
1981 Jan 25	- - - -	VEI (Explosivity Index)

1977 Aug 2 - 1980 Mar 12 Confirmed Eruption VEI: 3

Episode 1 | Eruption

Summit, NE flank (1700 m)

1977 Aug 2 - 1980 Mar 12

Evidence from Observations: Reported

List of 8 Events for Episode 1 at Summit, NE flank (1700 m)

Start Date	End Date	Event Type
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
1977 Aug 2	- - - -	VEI (Explosivity Index)
1978	- - - -	Fatalities
1980 Jan	- - - -	VEI (Explosivity Index)

1974 Apr 8 - 1974 Dec 16 (?) ± 15 days Confirmed Eruption VEI: 3

Episode 1 | Eruption

Summit and SW flank (3400-3600 m)

1974 Apr 8 - 1974 Dec 16 (?) ± 15 days

Evidence from Observations: Reported

List of 8 Events for Episode 1 at Summit and SW flank (3400-3600 m)

Start Date	End Date	Event Type
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
1974 Apr 8	- - - -	VEI (Explosivity Index)
1974 Aug 23	- - - -	VEI (Explosivity Index)

1971 Nov 16 ± 15 days - 1973 Dec 16 ± 15 days Confirmed Eruption VEI: 1

Episode 1 | Eruption

1971 Nov 16 ± 15 days - 1973 Dec 16 ± 15 days

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion	violent, strong, or large
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
1971 Nov	- - - -	VEI (Explosivity Index)

1971 Jun 16 ± 15 days - 1971 Jul 16 ± 15 days Confirmed Eruption VEI: 1

Episode 1 | Eruption

1971 Jun 16 ± 15 days - 1971 Jul 16 ± 15 days

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion	weak or small
- - - -	- - - -	Ash
1971 Jun	- - - -	VEI (Explosivity Index)

1970 May 26 - 1970 Dec 27 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1970 May 26 - 1970 Dec 27

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1970 May 26	- - - -	VEI (Explosivity Index)

1969 Sep 16 ± 15 days - 1969 Dec 16 ± 15 days Confirmed Eruption VEI: 2

Episode 1 | Eruption

1969 Sep 16 ± 15 days - 1969 Dec 16 ± 15 days

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1969 Sep	- - - -	VEI (Explosivity Index)

1968 Jul 3 - 1968 Jul 3 Confirmed Eruption VEI: 3

Episode 1 | Eruption

1968 Jul 3 - 1968 Jul 3

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Pyroclastic flow	Uncertain
- - - -	- - - -	Ash
- - - -	- - - -	Bombs
1968 Jul 3	- - - -	VEI (Explosivity Index)

1967 Jul 2 ± 182 days Confirmed Eruption VEI: 1

Episode 1 | Eruption

1967 Jul 2 ± 182 days - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1967	- - - -	VEI (Explosivity Index)

1965 Aug 16 ± 15 days - 1966 Dec 26 Confirmed Eruption VEI: 3

Episode 1 | Eruption

Summit, NE flank (Piip Crater)

1965 Aug 16 ± 15 days - 1966 Dec 26

Evidence from Observations: Reported

List of 11 Events for Episode 1 at Summit, NE flank (Piip Crater)

Start Date	End Date	Event Type
- - - -	- - - -	Seismicity (volcanic)
- - - -	- - - -	Seismicity (tremor)
- - - -	- - - -	Explosion
- - - -	- - - -	Lava fountains
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Lapilli
- - - -	- - - -	Bombs
1965 Aug	- - - -	VEI (Explosivity Index)
1966 Feb	- - - -	VEI (Explosivity Index)
1966 Oct 6	- - - -	VEI (Explosivity Index)

1963 Nov 13 - 1964 Dec 16 (?) ± 15 days Confirmed Eruption VEI: 1

Episode 1 | Eruption

1963 Nov 13 - 1964 Dec 16 (?) ± 15 days

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion	weak or small
	1963 Nov 13	- - - -	VEI (Explosivity Index)

1960 Dec 16 ± 15 days - 1963 Mar 22 (in or after) Confirmed Eruption VEI: 3

Episode 1 | Eruption

1960 Dec 16 ± 15 days - 1963 Mar 22 (in or after)

Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
1960 Dec	- - - -	VEI (Explosivity Index)
1962 Nov 13	- - - -	VEI (Explosivity Index)
1963 Mar 22	- - - -	VEI (Explosivity Index)

1959 Jan 3 Confirmed Eruption VEI: 1

Episode 1 | Eruption

1959 Jan 3 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion	weak or small
	1959 Jan 3	- - - -	VEI (Explosivity Index)

1958 May 18 - 1958 Aug 18 (in or after) Confirmed Eruption VEI: 1

Episode 1 | Eruption

East part of summit crater

1958 May 18 - 1958 Aug 18 (in or after)

Evidence from Observations: Reported

List of 4 Events for Episode 1 at East part of summit crater

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion	weak or small
- - - -	- - - -	Ash	weak or small
- - - -	- - - -	Earthquakes (undefined)	Before.
1958 May 18	- - - -	VEI (Explosivity Index)

1957 Jul 2 ± 182 days Confirmed Eruption VEI: 1

Episode 1 | Eruption

1957 Jul 2 ± 182 days - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion	weak or small
- - - -	- - - -	Ash
1957	- - - -	VEI (Explosivity Index)

1956 Jan 16 ± 15 days - 1956 Aug 2 Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit and SE flank (1500 m)

1956 Jan 16 ± 15 days - 1956 Aug 2

Evidence from Observations: Reported

List of 6 Events for Episode 1 at Summit and SE flank (1500 m)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Earthquakes (undefined)
- - - -	- - - -	Crater	Parasitic.
1956 Jan	- - - -	VEI (Explosivity Index)
1956 Jul 27	- - - -	VEI (Explosivity Index)

1954 May 28 - 1954 Sep 16 ± 15 days Confirmed Eruption VEI: 2

Episode 1 | Eruption

1954 May 28 - 1954 Sep 16 ± 15 days

Evidence from Observations: Reported

List of 7 Events for Episode 1

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Lapilli
- - - -	- - - -	Bombs
- - - -	- - - -	Flames
- - - -	- - - -	Earthquakes (undefined)	weak or small
1954 May 28	- - - -	VEI (Explosivity Index)

1953 Jun 7 - 1953 Jun 25 Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit, NE flank (Belyankin Crater)

1953 Jun 7 - 1953 Jun 25

Evidence from Observations: Reported

List of 5 Events for Episode 1 at Summit, NE flank (Belyankin Crater)

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
1953 Jun 7	- - - -	VEI (Explosivity Index)

1951 Nov 19 - 1951 Nov 30 Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit, NE flank (Bylinkina, 950 m)

1951 Nov 19 - 1951 Nov 30

Evidence from Observations: Reported

List of 6 Events for Episode 1 at Summit, NE flank (Bylinkina, 950 m)

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Bombs
- - - -	- - - -	Scoria
1951 Nov 19	- - - -	VEI (Explosivity Index)

1949 May Confirmed Eruption VEI: 2

Episode 1 | Eruption

1949 May - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1949 May	- - - -	VEI (Explosivity Index)

1948 Aug Confirmed Eruption VEI: 2 (?)

Episode 1 | Eruption

1948 Aug - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1948 Aug	- - - -	VEI (Explosivity Index)

1946 Oct 23 - 1946 Nov 22 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

SE flank (Apakhonchich, ca. 1600 m)

1946 Oct 23 - 1946 Nov 22 (?)

Evidence from Observations: Reported

List of 7 Events for Episode 1 at SE flank (Apakhonchich, ca. 1600 m)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Phreatic activity
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Bombs
- - - -	- - - -	Earthquakes (undefined)	Before.
1946 Oct 23	- - - -	VEI (Explosivity Index)

1945 Jun 19 - 1945 Jul 7 Confirmed Eruption VEI: 3

Episode 1 | Eruption

SE flank (Yubileinoye, 1000-1450 m)

1945 Jun 19 - 1945 Jul 7

Evidence from Observations: Reported

List of 5 Events for Episode 1 at SE flank (Yubileinoye, 1000-1450 m)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Crater	Parasitic.
1945 Jun 19	- - - -	VEI (Explosivity Index)

1944 Dec 9 - 1945 Jan 20 (in or after) Confirmed Eruption VEI: 3 (?)

Episode 1 | Eruption

1944 Dec 9 - 1945 Jan 20 (in or after)

Evidence from Observations: Reported

List of 6 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Avalanche
- - - -	- - - -	Ash
1944 Dec 9	- - - -	VEI (Explosivity Index)
1945 Jan 1	- - - -	VEI (Explosivity Index)

1937 Apr 3 - 1939 Mar Confirmed Eruption VEI: 3

Episode 1 | Eruption

Summit, east flank (Bilyukai)

1937 Apr 3 - 1939 Mar

Evidence from Observations: Reported

List of 6 Events for Episode 1 at Summit, east flank (Bilyukai)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Crater	Parasitic.
1937 Apr 3	- - - -	VEI (Explosivity Index)
1938 Feb 7	- - - -	VEI (Explosivity Index)

1935 Apr 21 - 1936 Nov 4 (in or after) Confirmed Eruption VEI: 3

Episode 1 | Eruption

1935 Apr 21 - 1936 Nov 4 (in or after)

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
1935 Apr 21	- - - -	VEI (Explosivity Index)
1936 Feb 18	- - - -	VEI (Explosivity Index)

1932 Jan 25 - 1932 Dec 26 ± 5 days Confirmed Eruption VEI: 2

Episode 1 | Eruption

NE flank (Kirgurich, Tuyla, Biokos)

1932 Jan 25 - 1932 Dec 26 ± 5 days

Evidence from Observations: Reported

List of 8 Events for Episode 1 at NE flank (Kirgurich, Tuyla, Biokos)

Start Date	End Date	Event Type	Event Remarks
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Cinder Cone
- - - -	- - - -	Ash
- - - -	- - - -	Lapilli
- - - -	- - - -	Bombs
- - - -	- - - -	Earthquakes (undefined)	Before.
1932 Jan 25	- - - -	VEI (Explosivity Index)

1931 Aug - 1931 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1931 Aug - 1931 Sep

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1931 Aug	- - - -	VEI (Explosivity Index)

1931 Mar 25 - 1931 Mar 27 Confirmed Eruption VEI: 4

Episode 1 | Eruption

1931 Mar 25 - 1931 Mar 27

Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Audible Sounds
1931 Mar 25	- - - -	VEI (Explosivity Index)

1929 Jun - 1929 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1929 Jun - 1929 Sep

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1929 Jun	- - - -	VEI (Explosivity Index)

1926 Mar 23 - 1926 Apr 7 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1926 Mar 23 - 1926 Apr 7

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1926 Mar 23	- - - -	VEI (Explosivity Index)

1925 Apr 4 - 1925 Oct 10 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1925 Apr 4 - 1925 Oct 10

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1925 Apr 4	- - - -	VEI (Explosivity Index)

1923 Aug - 1923 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1923 Aug - 1923 Sep

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1923 Aug	- - - -	VEI (Explosivity Index)

1922 May Confirmed Eruption VEI: 2

Episode 1 | Eruption

1922 May - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1922 May	- - - -	VEI (Explosivity Index)

1915 Jan Confirmed Eruption VEI: 2

Episode 1 | Eruption

1915 Jan - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1915 Jan	- - - -	VEI (Explosivity Index)

1913 Jan Confirmed Eruption VEI: 2

Episode 1 | Eruption

1913 Jan - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1913 Jan	- - - -	VEI (Explosivity Index)

1911 Nov Confirmed Eruption VEI: 2

Episode 1 | Eruption

1911 Nov - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1911 Nov	- - - -	VEI (Explosivity Index)

1910 Aug Confirmed Eruption VEI: 2

Episode 1 | Eruption

1910 Aug - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1910 Aug	- - - -	VEI (Explosivity Index)

1909 Jun Confirmed Eruption VEI: 2

Episode 1 | Eruption

1909 Jun - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1909 Jun	- - - -	VEI (Explosivity Index)

1907 Aug Confirmed Eruption VEI: 2

Episode 1 | Eruption

Summit and east flank

1907 Aug - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1 at Summit and east flank

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
1907 Aug	- - - -	VEI (Explosivity Index)

1904 Jan 31 ± 30 days - 1904 Jun 14 (in or after) Confirmed Eruption VEI: 2

Episode 1 | Eruption

1904 Jan 31 ± 30 days - 1904 Jun 14 (in or after)

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
1904 Jan 31 ± 30 days	- - - -	VEI (Explosivity Index)

1898 Feb 20 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1898 Feb 20 - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
1898 Feb 20	- - - -	VEI (Explosivity Index)

1896 Dec - 1897 Nov Confirmed Eruption VEI: 2

Episode 1 | Eruption

1896 Dec - 1897 Nov

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
1896 Dec	- - - -	VEI (Explosivity Index)

1890 Apr Confirmed Eruption VEI: 2

Episode 1 | Eruption

1890 Apr - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1890 Apr	- - - -	VEI (Explosivity Index)

1883 Jul - 1883 Aug Confirmed Eruption VEI: 2

Episode 1 | Eruption

1883 Jul - 1883 Aug

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1883 Jul	- - - -	VEI (Explosivity Index)

1882 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1882 Sep - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1882 Sep	- - - -	VEI (Explosivity Index)

1879 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1879 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1879	- - - -	VEI (Explosivity Index)

1878 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1878 Sep - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1878 Sep	- - - -	VEI (Explosivity Index)

1877 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1877 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1877	- - - -	VEI (Explosivity Index)

1865 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1865 Sep - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1865 Sep	- - - -	VEI (Explosivity Index)

1853 Oct - 1854 Feb 17 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1853 Oct - 1854 Feb 17

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1853 Oct	- - - -	VEI (Explosivity Index)

1852 Aug Confirmed Eruption VEI: 2

Episode 1 | Eruption

1852 Aug - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1852 Aug	- - - -	VEI (Explosivity Index)

1852 Feb - 1852 Mar Confirmed Eruption VEI: 2

Episode 1 | Eruption

1852 Feb - 1852 Mar

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1852 Feb	- - - -	VEI (Explosivity Index)

1848 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1848 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1848	- - - -	VEI (Explosivity Index)

1840 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1840 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1840	- - - -	VEI (Explosivity Index)

1829 Sep 9 Confirmed Eruption VEI: 4 (?)

Episode 1 | Eruption

1829 Sep 9 - Unknown

Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
1829 Sep 9	- - - -	VEI (Explosivity Index)

1819 - 1822 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

1819 - 1822 (?)

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Earthquakes (undefined)
1819	- - - -	VEI (Explosivity Index)
1821 Feb	- - - -	VEI (Explosivity Index)

1813 Feb Confirmed Eruption VEI: 2

Episode 1 | Eruption

1813 Feb - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1813 Feb	- - - -	VEI (Explosivity Index)

1812 Sep Confirmed Eruption VEI: 2

Episode 1 | Eruption

1812 Sep - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
1812 Sep	- - - -	VEI (Explosivity Index)

1807 Feb 1 ± 30 days Confirmed Eruption VEI: 2

Episode 1 | Eruption

1807 Feb 1 ± 30 days - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Flames
1807 Feb 1 ± 30 days	- - - -	VEI (Explosivity Index)

1791 Aug Confirmed Eruption VEI: 2

Episode 1 | Eruption

1791 Aug - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1791 Aug	- - - -	VEI (Explosivity Index)

1791 Apr Confirmed Eruption VEI: 2

Episode 1 | Eruption

1791 Apr - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1791 Apr	- - - -	VEI (Explosivity Index)

1789 Dec 1 - 1790 Feb Confirmed Eruption VEI: 2

Episode 1 | Eruption

1789 Dec 1 - 1790 Feb

Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Ash
- - - -	- - - -	Blocks
1789 Dec 1	- - - -	VEI (Explosivity Index)

1788 Aug Confirmed Eruption VEI: 2

Episode 1 | Eruption

1788 Aug - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1788 Aug	- - - -	VEI (Explosivity Index)

1788 Feb Confirmed Eruption VEI: 2

Episode 1 | Eruption

1788 Feb - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1788 Feb	- - - -	VEI (Explosivity Index)

1787 Sep Confirmed Eruption VEI: 2 (?)

Episode 1 | Eruption

1787 Sep - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion	Uncertain
	1787 Sep	- - - -	VEI (Explosivity Index)

1785 Nov Confirmed Eruption VEI: 2

Episode 1 | Eruption

1785 Nov - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1785 Nov	- - - -	VEI (Explosivity Index)

1772 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1772 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1772	- - - -	VEI (Explosivity Index)

1770 May Confirmed Eruption VEI: 2

Episode 1 | Eruption

1770 May - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1770 May	- - - -	VEI (Explosivity Index)

1767 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1767 - Unknown

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1767	- - - -	VEI (Explosivity Index)

1762 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1762 - Unknown

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
1762	- - - -	Fatalities
1762	- - - -	VEI (Explosivity Index)

1740 Confirmed Eruption

Episode 1 \| Eruption
1740 - Unknown				Evidence from Observations: Reported

1737 Sep 25 (?) - 1737 Nov 4 (?) Confirmed Eruption VEI: 2

Episode 1 | Eruption

1737 Sep 25 (?) - 1737 Nov 4 (?)

Evidence from Observations: Reported

List of 5 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
- - - -	- - - -	Ash
- - - -	- - - -	Earthquakes (undefined)
1737 Sep 25 (?)	- - - -	VEI (Explosivity Index)

1727 - 1731 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1727 - 1731

Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date	End Date	Event Type
- - - -	- - - -	Explosion
- - - -	- - - -	Lava flow
1727	- - - -	VEI (Explosivity Index)

1720 - 1721 Confirmed Eruption VEI: 2

Episode 1 | Eruption

1720 - 1721

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1720	- - - -	VEI (Explosivity Index)

1697 - 1698 Confirmed Eruption VEI: 3

Episode 1 | Eruption

1697 - 1698

Evidence from Observations: Reported

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	1697	- - - -	VEI (Explosivity Index)

0550 (?) Confirmed Eruption

Episode 1 | Eruption

0550 (?) - Unknown

Evidence from Isotopic: 14C (uncalibrated)

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	- - - -	- - - -	Cinder Cone

1050 BCE (?) Confirmed Eruption

Episode 1 | Eruption

1050 BCE (?) - Unknown

Evidence from Correlation: Tephrochronology

List of 1 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion

3950 BCE (?) Confirmed Eruption

Episode 1 | Eruption

3950 BCE (?) - Unknown

Evidence from Isotopic: 14C (uncalibrated)

List of 1 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion

Deformation History

There is data available for 2 deformation periods. Expand each entry for additional details.

Deformation during 2001 - 2005 [Uplift; Observed by leveling, triangulation]

Start Date: 2001

Stop Date: 2005

Direction: Uplift

Method: leveling, triangulation

Magnitude: Unknown

Spatial Extent: Unknown

Latitude: Unknown

Longitude: Unknown

Remarks: Adventive and summit eruptions

Reference List: Fedotov et al. 2007; Fedotov et al. 2010.

Full References:

Fedotov, S. A., and N. A. Zharinov, 2007. On the eruptions, deformation, and seismicity of Klyuchevskoy volcano, Kamchatka in 1986-2005 and the mechanisms of its activity. J. Volcanol. Seismol., 1, 71-97. https://doi.org/10.1134/S0742046307020017

Fedotov, S. A., Zharinov, N. A., & Gontovaya, L. I., 2010. The magmatic system of the Klyuchevskaya group of volcanoes inferred from data on its eruptions, earthquakes, deformation, and deep structure. Journal of Volcanology and Seismology, 4(1), 1-33.

Deformation during 1978 - 1987 [Variable (uplift / subsidence); Observed by aerial survey, leveling]

Start Date: 1978

Stop Date: 1987

Direction: Variable (uplift / subsidence)

Method: aerial survey, leveling

Magnitude: 10000.000 cm

Spatial Extent: Unknown

Latitude: Unknown

Longitude: Unknown

Remarks: Filling of summit crater, eruption

Reference List: Fedotov et al. 1992; Fedotov and Zharinov 2007; Fedotov et al. 2010.

Full References:

Fedotov, S. A., Gorelchik, V. I., & Zharinov, N. A., 1992. Deformation, Earthquakes and Mechanism of Activity of Klyuchevskoy Volcano. In Volcanic Seismology (pp. 20-44). Springer Berlin Heidelberg.

Emission History

There is data available for 6 emission periods. Expand each entry for additional details.

Emissions during 2013 Oct 13 - 2013 Oct 20 [55 kt SO₂ at 7 km altitude]

Start Date: 2013 Oct 13	Stop Date: 2013 Oct 20	Method: Satellite (Aura OMI)
SO₂ Altitude Min: 7 km	SO₂ Altitude Max: 10 km	Total SO₂ Mass: 55 kt

Data Details

Date Start	Date End	Assumed SO₂ Altitude	SO₂ Algorithm	SO₂ Mass
20131020		8.0		5.000
20131019		9.0		10.000
20131018		10.0		30.000
20131017		10.0		2.000
20131016		10.0		2.000
20131015		10.0		2.000
20131014		7.0		2.000
20131013		7.0		2.000

Emissions during 2013 Nov 19 - 2013 Nov 19 [2 kt SO₂ at 12 km altitude]

Start Date: 2013 Nov 19	Stop Date: 2013 Nov 19	Method: Satellite (Aura OMI)
SO₂ Altitude Min: 12 km	SO₂ Altitude Max: 12 km	Total SO₂ Mass: 2 kt

Data Details

Date Start	Date End	Assumed SO₂ Altitude	SO₂ Algorithm	SO₂ Mass
20131119		12.0		2.000

Emissions during 2007 Apr 30 - 2007 Jul 15 [176 kt SO₂ at 6 km altitude]

Start Date: 2007 Apr 30	Stop Date: 2007 Jul 15	Method: Satellite (Aura OMI)
SO₂ Altitude Min: 6 km	SO₂ Altitude Max: 10 km	Total SO₂ Mass: 176 kt

Data Details

Date Start	Date End	Assumed SO₂ Altitude	SO₂ Algorithm	SO₂ Mass
20070715		6.0		2.000
20070714		6.0		2.000
20070713		6.0		2.000
20070712		6.0		2.000
20070711		7.0		2.000
20070710		7.0		2.000
20070709		7.0		2.000
20070708		6.0		2.000
20070707		6.0		2.000
20070706		6.0		2.000
20070705		6.0		2.000
20070704		6.0		2.000
20070703		6.0		2.000
20070702		6.0		2.000
20070701		7.0		5.000
20070630		10.0		10.000
20070629		9.0		10.000
20070628		9.0		2.000
20070627		7.0		2.000
20070626		7.0		2.000
20070625		7.0		2.000
20070624		7.0		2.000
20070623		7.0		2.000
20070622		7.0		2.000
20070621		7.0		2.000
20070620		7.0		2.000
20070619		7.0		2.000
20070618		7.0		2.000
20070617		7.0		2.000
20070616		7.0		2.000
20070615		7.0		2.000
20070614		7.0		2.000
20070613		7.0		2.000
20070612		7.0		2.000
20070611		7.0		2.000
20070610		7.0		2.000
20070609		7.0		2.000
20070608		7.0		2.000
20070607		7.0		2.000
20070606		7.0		2.000
20070605		7.0		2.000
20070604		7.0		2.000
20070603		7.0		2.000
20070602		7.0		2.000
20070601		7.0		2.000
20070531		7.0		2.000
20070530		7.0		2.000
20070529		7.0		2.000
20070528		7.0		2.000
20070527		10.0		5.000
20070526		8.0		2.000
20070525		8.0		2.000
20070524		8.0		2.000
20070523		8.0		2.000
20070522		8.0		2.000
20070521		8.0		2.000
20070520		8.0		2.000
20070519		8.0		2.000
20070518		8.0		2.000
20070517		8.0		2.000
20070516		9.0		2.000
20070515		9.0		2.000
20070514		8.0		2.000
20070513		8.0		2.000
20070512		8.0		2.000
20070511		8.0		2.000
20070510		8.0		2.000
20070509		8.0		2.000
20070508		6.0		2.000
20070507		6.0		2.000
20070506		6.0		2.000
20070505		6.0		2.000
20070504		6.0		2.000
20070503		6.0		2.000
20070502		6.0		2.000
20070501		7.0		2.000
20070430		7.0		2.000

Emissions during 1994 Oct 01 - 1994 Oct 01 [150 kt SO₂ at 15 km altitude]

Start Date: 1994 Oct 01	Stop Date: 1994 Oct 01	Method: Satellite (Meteor-3 TOMS)
SO₂ Altitude Min: 15 km	SO₂ Altitude Max: 15 km	Total SO₂ Mass: 150 kt

Data Details

Date Start	Date End	Assumed SO₂ Altitude	SO₂ Algorithm	SO₂ Mass
19941001		15.0		150.000

Emissions during 1990 Jan 30 - 1990 Jan 30 [10 kt SO₂ at 10 km altitude]

Start Date: 1990 Jan 30	Stop Date: 1990 Jan 30	Method: Satellite (Nimbus-7 TOMS)
SO₂ Altitude Min: 10 km	SO₂ Altitude Max: 10 km	Total SO₂ Mass: 10 kt

Data Details

Date Start	Date End	Assumed SO₂ Altitude	SO₂ Algorithm	SO₂ Mass
19900130		10.0		10.000

Emissions during 1987 Feb 19 - 1987 Feb 19 [10 kt SO₂ at 9 km altitude]

Start Date: 1987 Feb 19	Stop Date: 1987 Feb 19	Method: Satellite (Nimbus-7 TOMS)
SO₂ Altitude Min: 9 km	SO₂ Altitude Max: 9 km	Total SO₂ Mass: 10 kt

Data Details

Date Start	Date End	Assumed SO₂ Altitude	SO₂ Algorithm	SO₂ Mass
19870219		9.0		10.000

Photo Gallery

Four volcanoes of the Klyuchevskaya volcano group are visible in this north-looking view. A gas plume emanates from the summit of Bezymianny in the foreground, which is dwarfed by Kamen behind it. Klyuchevskoy is to the upper right, and Ushkovsky is on the left horizon. Krestovsky forms the rounded summit and the glacier-covered Ushkovsky caldera is visible to the far-left.

Photo by Oleg Volynets (Institute of Volcanology, Petropavlovsk).

Lava extrudes from a vent on the SE flank of Klyuchevskoy volcano in 1988 with Kamen volcano in the background. Long-term activity at Klyuchevskoy has produced both explosive eruptions and lava effusion, taking place from vents at the summit and on the flanks. The steep eastern flank of Kamen resulted from collapse of the summit about 1,200 years ago, resulting in a massive debris avalanche that traveled approximately 30 km.

Photo courtesy of Anatolii Khrenov, 1988 (Institute of Volcanology, Petropavlovsk).

Following renewed explosive activity in the Klyuchevskoy summit crater starting on 8 April 1974, an eruption began on 23 August from a vent on the SW flank. This was the highest flank vent location to date in Klyuchevskoy’s recorded history. This photo shows lava fountaining and effusion of a lava flow from the SW-flank vent. The eruption continued until the end of the year.

Photo by N. Smelov, 1974 (Institute of Volcanology, Petropavlovsk).

This photo from the NE shows almost all the volcanoes of Klyuchevskaya volcano group, which draws its name from Klyuchevskoy volcano (center). The volcano producing the plume in the left background is Bezymianny. Other volcanoes visible on the horizon are Zimina (far left), Tolbachik (behind Bezymianny), Kamen (left of Klyuchevskoy), and Ushkovsky (right). The NE flank of Klyuchevskoy contains smaller cones produced by more than 100 flank eruptions during the past 3,000 years.

Photo by V.A. Podtabachny (courtesy of Anatolii Khrenov, Institute of Volcanology, Petropavlovsk).

A lava flow travels down the NW flank of Klyuchevskoy in this January 1986 view from the town of Klyuchi. Explosive activity commenced at the summit on 16 August 1985 and lava flow emission began on 5 November, accompanied by intensive summit explosive activity. On 2 December strong phreatic explosions from a NW flank fissure ejected material that reached 10 km, and on 1-2 December, a mudflow traveled 35 km. The summit crater eruption ended on 21 January 1986.

Photo by Alexander Belousov, 1986 (Institute of Volcanology, Kamchatka, Russia).

An ash plume erupting from the summit crater of Kamchatka's Kliuchevskoy volcano on 9 February 1987, traveling to the west. Ashfall from earlier eruptions darkens the southern flank of the volcano and several lahar deposits are visible. Explosive eruptions from the summit crater during 1986-1990 were accompanied by lava flows from both summit and flank vents.

Photo by Alexander Belousov, 1987 (Institute of Volcanology, Kamchatka, Russia).

An ash plume erupts from the summit of Klyuchevskoy on 16 February 1987. Long-term activity includes both explosive and effusive activity from summit and flank vents. This view from the south shows Bezymianny producing a small plume at the lower left, Kamen at the left center, and the broader Ushkovsky on the left horizon.

Photo by Alexander Belousov, 1987 (Institute of Volcanology, Kamchatka, Russia).

An ash plume drifts from the summit of Klyuchevskoy in 1974 above volcanologists at a field camp of the Institute of Volcanology in Petropavlovsk. Renewed explosive summit crater activity began 8 April and lava fountaining started on 18 May. Summit activity was followed by an eruption on the SW flank on 23 August. Frequent eruptions have occurred at Klyuchevskoy from both summit and flank vents.

Photo by Yuri Doubik, 1974 (Institute of Volcanology, Petropavlovsk).

An ash plume from Klyuchevskoy in 1979 is dispersed in front of the sun in this view looking from the SW. This was part of a dominantly explosive eruption that took place from August 1977 until 1980. The eruption concluded with explosive activity and lava effusion from a flank vent during 5-12 March 1980. Ushkovsky is to the right, with the small Sredny cone in the center.

Photo by Yuri Doubik, 1979 (Institute of Volcanology, Petropavlovsk).

Klyuchevskoy rises above a volcanological field camp on the SE flank. Numerous flank vents have formed on its flanks, including one that produced the Apakhonchich lava flow near this location in 1946.

Photo by Yuri Doubik, 1982 (Institute of Volcanology, Petropavlovsk).

A volcanologist from the Institute of Volcanology in Petropavlovsk, shielded from the intense heat in a reflective suit, extracts a glowing sample of lava from a flank vent of Klyuchevskoy volcano in 1983. Geochemical analysis of lava samples is used to understand the eruption dynamics and the magmatic history of the volcano. Eruptions of flank and summit lava flows are common here. Protective clothing is always needed when working on active volcanoes, but sampling at lava flows such as this is rare.

Photo by A. Ozerov, 1983 (courtesy of Yuri Doubik, Institute of Volcanology, Petropavlovsk).

Gas-and-steam plume emissions occurred simultaneously from vents on the SW flank and the summit of Klyuchevskoy volcano in 1983. The SW-flank vent within a 200-m-long fissure produced the dark lava flow that melted the glacier surface, providing a channel for the lava flow and producing lahars that traveled 15 km. The flank eruption began on 8 March and was initially was restricted to a glacier gorge, but then bifurcated, forming a small lava field. Intermittent summit crater explosive activity had been occurring since October 1982.

Photo by Yuri Doubik, 1983 (Institute of Volcanology, Petropavlovsk).

An incandescent lava flow erupts from an E-flank vent on Klyuchevskoy in 1983 while an ash plume rises from the summit crater. An eruption from an east flank fissure began on 8 March 1983. A scoria cone that formed during the initial stage was the source of the flank activity. Strombolian eruptions during the main phase were followed by lava emission at varying rates. Flank activity was preceded by summit crater gas-and-ash emissions beginning 7 October 1982.

Photo by Yuri Doubik, 1983 (Institute of Volcanology, Petropavlovsk).

Clouds drape the margins of the glacier-covered summit caldera of Ushkovsky (Plosky) volcano in the foreground. Two of the highest volcanoes in Kamchatka, Klyuchevskoy (left) and Kamen (right) rise above the layer of clouds to the SE. A small ash plume drifts above the summit of Klyuchevskoy, one of Kamchatka's most active volcanoes.

Photo by Yuri Doubik (Institute of Volcanology, Petropavlovsk).

Two of Kamchatka's highest volcanoes rise above the clouds. Their differing morphologies reflect contrasting geologic histories. Construction of extensively eroded Kamen volcano (left) took place during the Pleistocene. It has been relatively inactive since. Its eastern (right) side was removed by a massive landslide about 1,200 years ago, leaving the steep escarpment. Symmetrical Klyuchevskoy, in contrast, is one of Kamchatka's youngest and most active volcanoes.

Photo by Yuri Doubik (Institute of Volcanology, Petropavlovsk).

Steam rises from the margins of an active lava flow from a SW-flank vent of Klyuchevskoy in 1974. Renewed summit crater explosive activity began 8 April, with lava fountaining beginning 18 May. Increasing seismicity preceded the 23 August outbreak from 3,400-3,600 m elevation on the SW flank. Lava effusion continued until December.

Photo by I.T. Kirsanov, 1974 (courtesy of Oleg Volynets, Institute of Volcanology, Petropavlovsk).

Klyuchevskoy has produced many small to moderate-volume explosive and effusive eruptions without major periods of inactivity. More than 100 flank eruptions have occurred during the past roughly 3,000 years, with most craters and cones occurring on the NE (seen here) and SE flanks, at elevations of 500-3,600 m.

Photo by E.Y. Zhdanova (courtesy of Oleg Volynets, Institute of Volcanology, Petropavlovsk).

Kamen (left), Klyuchevskoy (right), and the broad snow-capped Ushkovsky behind them to the west, form the northern end of the Klyuchevskaya volcano group. Ushkovsky consists of the flat-topped Ushkovsky volcano on the left, which is capped by an ice-filled 4.5 x 5.5 km caldera, and the adjacent slightly higher Krestovsky peak on the right.

Photo by Phil Kyle, New Mexico Institute of Mining and Technology, 1996 (courtesy of Vera Ponomareva, IUGG, Petropavlovsk).

Symmetrical Klyuchevskoy and the eroded Ushkovsky edifice are seen here SW of the town of Klyuchi. The small Sredny cone, constructed on the eastern flank of Ushkovsky, occupies the saddle between them. Klyuchevskoy is one of Kamchatka's most active volcanoes and Ushkovsky has also erupted in historical time.

Photo by Vera Ponomareva, 1975 (Institute of Volcanic Geology and Geochemistry, Petropavlovsk).

Kamen towers above the Karpinski scoria cone (left) on the ESE flank of Klyuchevskoy volcano with lahar deposits from Klyuchevskoy in the foreground. The eastern side of Kamen was removed by a massive volcanic landslide about 1,200 years ago.

Photo by Vera Ponomareva, 1975 (Institute of Volcanic Geology and Geochemistry, Petropavlovsk).

Klyuchevskoy volcano has had more than 100 flank eruptions during the past 3,000 years. The conical stratovolcano is one of the youngest and largest of Kamchatka's volcanoes, having produced 300 km³ of material since the early Holocene.

Photo by Vera Ponomareva, 1976 (Institute of Volcanic Geology and Geochemistry, Petropavlovsk).

Incandescent Strombolian ejecta rises above a new scoria cone in the summit crater of Klyuchevskoy volcano on 22 May 2007. Lava flows travel down the NW flank. Strombolian eruptions had begun on 15 February 2007, and explosive activity and lava effusion continued until 15 July.

Photo by Yu. Demyanchuk, 2007 (KVERT).

Klyuchevskoy is seen from the north on 31 May 2007, showing an ash plume from the summit crater and a larger steam plume rising from the eastern flank where lava flows were interacting with snow and ice.

Photo by Yu. Demyanchuk, 2007 (KVERT).

Strombolian eruptions produce incandescent plumes from the summit crater and lava flows descend the NW flanks of the volcano on 27 May 2007 and an ash-and-steam plume rises from the lava flow margins. Strombolian eruptions had begun on 15 February 2007 at the summit crater. Intermittent explosive activity continued, and lava flows began traveling down the NW flank on 29 March. Steam-and-ash plumes reached a maximum altitude of 10 km on May 27 and the last ash plume was observed on 15 July, after which steam plumes were observed.

Photo by Yu. Demyanchuk, 2007 (KVERT).

The northern flank of Klyuchevskoy is seen here on 8 July 2015. A gas-and-steam plume is emanating from the summit crater and is dispersed to the W by the wind.

Photo by Janine Krippner, 2015.

GVP Map Holdings

Maps are not currently available due to technical issues.

Smithsonian Sample Collections Database

The following 9 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections, and may be availble for research (contact the Rock and Ore Collections Manager). Catalog number links will open a window with more information.

Catalog Number	Sample Description	Lava Source	Collection Date
NMNH 116514-1	Basalt	SUMMIT ERUPTION	--
NMNH 116543-4	Basalt	--	--
NMNH 116543-5	Basalt	--	--
NMNH 116543-6	Basalt	--	--
NMNH 116556-14	Dacitic Andesite	--	--
NMNH 116556-17	Basalt	--	--
NMNH 116556-18	Basalt	--	--
NMNH 116556-19	Basalt	--	--
NMNH 116556-20	Basalt	--	--

External Sites

Copernicus Browser

The Copernicus Browser replaced the Sentinel Hub Playground browser in 2023, to provide access to Earth observation archives from the Copernicus Data Space Ecosystem, the main distribution platform for data from the EU Copernicus missions.

MIROVA

Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.

MODVOLC Thermal Alerts

Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.

WOVOdat
   Single Volcano View
   Temporal Evolution of Unrest
   Side by Side Volcanoes

WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.

GVMID Data on Volcano Monitoring Infrastructure The Global Volcano Monitoring Infrastructure Database GVMID, is aimed at documenting and improving capabilities of volcano monitoring from the ground and space. GVMID should provide a snapshot and baseline view of the techniques and instrumentation that are in place at various volcanoes, which can be use by volcano observatories as reference to setup new monitoring system or improving networks at a specific volcano. These data will allow identification of what monitoring gaps exist, which can be then targeted by remote sensing infrastructure and future instrument deployments.

Volcanic Hazard Maps

The IAVCEI Commission on Volcanic Hazards and Risk has a Volcanic Hazard Maps database designed to serve as a resource for hazard mappers (or other interested parties) to explore how common issues in hazard map development have been addressed at different volcanoes, in different countries, for different hazards, and for different intended audiences. In addition to the comprehensive, searchable Volcanic Hazard Maps Database, this website contains information about diversity of volcanic hazard maps, illustrated using examples from the database. This site is for educational purposes related to volcanic hazard maps. Hazard maps found on this website should not be used for emergency purposes. For the most recent, official hazard map for a particular volcano, please seek out the proper institutional authorities on the matter.

IRIS seismic stations/networks

Incorporated Research Institutions for Seismology (IRIS) Data Services map showing the location of seismic stations from all available networks (permanent or temporary) within a radius of 0.18° (about 20 km at mid-latitudes) from the given location of Klyuchevskoy. Users can customize a variety of filters and options in the left panel. Note that if there are no stations are known the map will default to show the entire world with a "No data matched request" error notice.

UNAVCO GPS/GNSS stations

Geodetic Data Services map from UNAVCO showing the location of GPS/GNSS stations from all available networks (permanent or temporary) within a radius of 20 km from the given location of Klyuchevskoy. Users can customize the data search based on station or network names, location, and time window. Requires Adobe Flash Player.

DECADE Data

The DECADE portal, still in the developmental stage, serves as an example of the proposed interoperability between The Smithsonian Institution's Global Volcanism Program, the Mapping Gas Emissions (MaGa) Database, and the EarthChem Geochemical Portal. The Deep Earth Carbon Degassing (DECADE) initiative seeks to use new and established technologies to determine accurate global fluxes of volcanic CO₂ to the atmosphere, but installing CO₂ monitoring networks on 20 of the world's 150 most actively degassing volcanoes. The group uses related laboratory-based studies (direct gas sampling and analysis, melt inclusions) to provide new data for direct degassing of deep earth carbon to the atmosphere.

Large Eruptions of Klyuchevskoy

Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).

EarthChem

EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).