Craig Miller

Ash emission has stopped at Whakaari/White Island. Volcanic Alert Level is lowered to Level 1.

Published: Mon Dec 7 2020 3:30 PM
Volcanic Activity Bulletin
Volcanic Activity BulletinWI – 2020/17
Mon Dec 7 2020 3:30 PM; Whakaari/White Island Volcano
Volcanic Alert Level is lowered to 1
Aviation Colour Code is lowered to Green

Observations in the last week show that ash is no longer being emitted from Whakaari. Levels of gas emission have also decreased, and other monitoring indicators remain low. The Volcanic Alert Level is lowered to Level 1.

Observations and monitoring data over the last 2 weeks indicate that Whakaari/White Island has been progressing on a gradual trend back to lower levels of volcanic unrest that are typical of the long-term behaviour of this volcano. An observation flight on 2nd December confirmed that ash emission from the volcano has now stopped. Satellite observations in the last week have also not detected any ash in the steam plume. Hot steam and gas emissions continue from the active vents.

A gas measuring flight on 2nd December showed that the main volcanic gases, Carbon dioxide (CO2) and Sulphur dioxide (SO2) have returned to lower levels, like those seen in September 2020. The level of volcanic seismic tremor and the number of local earthquakes remain low. Ground deformation data from satellite measurements indicate continued subsidence around the active vent area at the back of the crater lake as well as ongoing local subsidence of the Main Crater wall, south and west of the 2019 active vents.

These observations indicate that Whakaari/White Island is now back at a low level of unrest. The Volcanic Alert Level is lowered to Level 1 (from 2) and the Aviation Colour Code is lowered to Green (from Yellow).

Recent heavy rain has improved the camera views from the Factory camera, however other cameras remain affected by ash covering. All other monitoring instrumentation is currently operational.

The Volcanic Alert Level reflects the current level of volcanic unrest or activity and is not a forecast of future activity. Volcanic Alert Level 1 indicates the primary hazards are those expected during volcanic unrest; including discharge of steam and hot volcanic gases, earthquakes, landslides and hydrothermal activity. While Volcanic Alert Level 1 is mostly associated with environmental hazards, eruptions can still occur with little or no warning. The main plausible triggers for a sudden eruption remain the collapse of unstable material in an active vent and the possible ingress of water underground onto the shallow magma body.

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

GNS Science and our National Geohazards Monitoring Centre continuously monitor Whakaari/White Island for changes in activity. Further updates will be provided as needed.

Craig Miller Duty Volcanologist

Media Contact: 021 574 541 or media@gns.cri.nz