According to GeoNet water filled in the vents of Whakaari/White Island’s 2019 Primary Crater based on 18 May webcam views. During an observation overflight on 27 May scientists confirmed the new lakelet and noted that several active steam and gas vents were under water. Thermal infrared measurements indicated that temperatures had cooled significantly. Gas emissions had not notably changed over the previous few months. A persistent gas-and-steam plume likely produced acid rain on the island. A period of low-energy volcanic tremor began at around 0400 on 1 June and lasted for two hours. Activity rapidly returned to low levels afterwards. Overall, seismicity was at background levels. The Volcanic Alert Level remained at 1 and the Aviation Color Code remained at Green.

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