GeoNet reported that a minor eruption at Whakaari/White Island occurred at around 0820 on 24 May and produced a vigorous steam-and-gas plume that rose 2-3 km high. There was no clear indication of ash in the plume at the time, based on webcam images. The Volcanic Alert Level was raised to 3 (on a scale of 0-5) and the Aviation Color Code was raised to Orange (the third level on a four-color scale). Steam emissions had returned to normal conditions by 1045. During an overflight of the island later that day scientists observed ash deposits downwind, on the N part of the island. Geysering at the crater lake that had been ongoing for months was stronger, ejecting material 20-30 m high for periods of several seconds. The vent area was obscured by gas-and-steam emissions. The level of the crater lake had subsided and exposed parts of the lake floor. The eruption was much smaller than the December 2019 eruption. At 1700 the Volcanic Alert Level was lowered back down to 2 and the Aviation Color Code was lowered back to Yellow. GeoNet noted that there were no instruments on the island and therefor a lack of real-time monitoring data; monitoring was conducted with a webcam located in Whakatane, satellite images, and observational and gas measurement overflights.

A second minor eruption occurred at 0810 on 25 May, again prompting GeoNet to raise the Volcanic Alert Level to 3 and the Aviation Color Code to Orange. The eruption produced a vigorous steam-and-gas plume that rose above the island, similar to the day before. There were no clear indications of ash in the plume based on the webcam view. According to the Wellington VAAC ash was not identifiable in a satellite image from 1107 on 25 May. In a statement issued at 1445, GeoNet noted that intermittent ejections of gas and steam continued to be visible throughout the day. No further activity was observed over the next few days; the Volcanic Alert Level was lowered to 2 and the Aviation Color Code was lowered to Yellow at 1500 on 29 May. GeoNet noted that analysis of data collected during a 27 May overflight indicated elevated levels of magmatic gas compared to previous observations in April and early May.

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