Whakaari/White Island: Vent temperature and gas output decreases; volcanic unrest continues

Published: Tue Jan 18 2022 10:50 AM

Volcanic Activity BulletinWI – 2022/01
Tue Jan 18 2022 10:00 AM; Whakaari/White Island Volcano
Volcanic Alert Level remains at 2
Aviation Colour Code remains at Yellow

Data from an observation flight at Whakaari/White Island last week show a substantial decrease in the active vent temperature and a small decrease in the gas output. The state of moderate to heightened unrest continues. The Volcanic Alert Level remains at Level 2.

Last week GNS scientists undertook flights around Whakaari to collect visual observations, measure the levels of gas being emitted, and the temperature of the active vent area.

The maximum temperature measured in the active vent area was 191 °C, a decline from 516 °C in December 2021. During September-November 2021, temperatures ranged from 202 °C to 264 °C. Temperatures over 500 °C were also recently observed in July and August 2021.

A gas measuring flight was also made last week recording a slight decrease of the volcanic gas output that was measured at the volcano in December 2021. Both Sulphur Dioxide (SO2) and Carbon Dioxide (CO2) gas emission rates are slightly below a 10-year average.

The temperature and gas emission observations are consistent with hot gas continuing to be released from the molten rock (magma) beneath the volcano at variable rates.

Minor amounts of ash emission continue to be observed, similar to most of our recent observation flights. Ash deposits remain limited to areas close to the active vents. Further intermittent ash emission may continue to occur.

The water level of the lake has receded during the recent spell of fine, dry weather.

The current level of activity is consistent with moderate to heightened levels of unrest. As such the Volcanic Alert Level remains at 2 and the Aviation Colour Code remains at Yellow.

As noted previously, our on-island equipment has degraded. This means that while we are getting some data, it is not real time and it is not complete. We are continuing to work on restoration options.

The Volcanic Alert Level reflects the current level of volcanic unrest or activity and is not a forecast of future activity. While Volcanic Alert Level 2 is mostly associated with volcanic unrest hazards (including discharge of steam and hot volcanic gases, earthquakes, landslides, and hydrothermal activity), potential for eruption hazards also exists and eruptions can still occur with little or no warning.

Further information about the volcanic alert levels and what they mean can be found here.

GNS Science and its National Geohazards Monitoring Centre continue to monitor Whakaari/White Island for further changes in unrest.

Steven Sherburn

Duty Volcanologist

Media Contact: 021 574541 or media@gns.cri.nz