The Darwin VAAC reported daily ash plumes at Manam during 25-29 May. At 0720 on 25 May an ash plume rose to 2.4 km (8,000 ft) a.s.l. and drifted W, and dissipated within 30 minutes. Ash plumes rose to 2.1 km (7,000 ft) a.s.l. and drifted NW during 25-26 May. An eruptive event, observed at 0657 on 27 May by RVO and webcam images, produced an ash plume that rose to 2.4 km a.s.l. based on webcam views; weather clouds prevented satellite views of the emissions. On 28 May an ash plume rose to 2.1 km a.s.l. and drifted NE. A thermal anomaly over the volcano was visible following the emission. On 29 May diffuse ash plumes rose to 2.1-2.4 km a.s.l. and drifted in multiple directions.

Geological Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical basaltic-andesitic stratovolcano to its lower flanks. These valleys channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island's shoreline on the northern, southern, and western sides. Two summit craters are present; both are active, although most observed eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent eruptions, typically of mild-to-moderate scale, have been recorded since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)