Report on Whakaari/White Island (New Zealand) — 27 January-2 February 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
27 January-2 February 2021
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2021. Report on Whakaari/White Island (New Zealand). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 27 January-2 February 2021. Smithsonian Institution and US Geological Survey.
37.52°S, 177.18°E; summit elev. 294 m
All times are local (unless otherwise noted)
GeoNet reported that during the previous year temperatures of Whakaari/White Island’s steam and gas vents were regularly captured during helicopter overflights. These data showed a downward trend from temperatures of over 700 degrees Celsius in February 2020 to temperatures around 300 degrees Celsius recorded on 21 January. The recent gas-emission temperatures were similar to those measured in July 2018.
There was no evidence of eruptive activity observed during overflights in January nor signs of collapse in or near the active vents. A small amount of water had ponded on the 1978/90 Crater floor. Gas continued to be emitted from the active vents and from cooling lava that had erupted in December 2019, though the emission rates were the lowest recorded since that eruption. 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.