On 7 January GeoNet Data Centre reported that the Aviation Colour Code for White Island was lowered to Yellow (second lowest on a four-color scale) and the Volcanic Alert Level was lowered to 1. A spiny lava dome in the crater formed on 5 August was first clearly observed on 10 December. Observations on 20 December indicated that the dome had not changed. Scientists visited the area on 1 January and again observed no changes. They measured temperatures of 200-240 degrees Celsius from the lava dome and 70-80 degrees from the nearby hot lake, and observed lots of gas coming from the lake. The report also indicated continuing elevated levels of tremor.

Geological Summary. The uninhabited Whakaari/White Island is the 2 x 2.4 km emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The island consists of two overlapping andesitic-to-dacitic stratovolcanoes. The SE side of the crater is open at sea level, with the recent activity centered about 1 km from the shore close to the rear crater wall. Volckner Rocks, sea stacks that are remnants of a lava dome, lie 5 km NW. Descriptions of volcanism since 1826 have included intermittent moderate phreatic, phreatomagmatic, and Strombolian eruptions; activity there also forms a prominent part of Maori legends. The formation of many new vents during the 19th and 20th centuries caused rapid changes in crater floor topography. Collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project. Explosive activity in December 2019 took place while tourists were present, resulting in many fatalities. The official government name Whakaari/White Island is a combination of the full Maori name of Te Puia o Whakaari ("The Dramatic Volcano") and White Island (referencing the constant steam plume) given by Captain James Cook in 1769.

Source: GeoNet