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Whakaari alert level lowered to one

Tomorrow marks one year since the fatal eruption at Whakaari/White Island. Photo: Daniel Hines/SunLive.

Almost a year on from the fatal eruption which left 22 people dead, the alert level at Whakaari/White Island has been lowered to one.

Tomorrow marks the one year anniversary of when the Bay of Plenty volocano erupted with 47 people on the island.

Observations in the last week show that ash is no longer being emitted from Whakaari, says GNS duty volcanologist Craig Miller.

"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 December 2, confirmed that ash emission from the volcano has now stopped.

Miller says satellite observations in the last week have also not detected any ash in the steam plume.

He says hot steam and gas emissions continue from the active vents.

"A gas measuring flight on December 2 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, says Miller.

"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

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