White Island (Whakaari): Lake disappears, strong fumarole emissions

Published: Mon Oct 3 2016 4:20 PM

Volcanic Alert BulletinWI – 2016/13
Mon Oct 3 2016 4:20 PM; White Island Volcano
Volcanic Alert Level remains at 1
Aviation Colour Code remains Yellow

Observations during a visit to White Island on Friday have confirmed that a large part of the gas is now being emitted from one ‘joint’ vent on the lava outcrop at the back of the crater. The joining of the vents has resulted in a stronger and noisier gas flow from this vent. The temperature has declined slightly, it is now only 250 °C, down from 300 °C.

The other significant change is the disappearance of the shallow lake. The lake was about 3 m deep and has now drained to leave some small ponds. The water level started to drop on the 24th and by the 26th of September the lake was gone and remains so. The seismic and acoustic activity remains low, and although the gas flux is difficult to measure (due to wind conditions) it doesn’t appear to have changed substantially.

Recently we have also experienced some issues with the power supplies for some of our remote monitoring gear, mostly related to the accumulative effect of the weather (little sun) and ash on the solar panels. One of the cameras had an issue with the data card. On Friday a team visited the island armed with a new camera, batteries, glass cleaning gear, thermal IR, and gas measuring equipment.

The easterly conditions prevailing when the team got there restricted their access to the summit area. This meant the West Rim camera couldn’t be replaced and they were also unable to make detailed gas measurements as planned. They could visit the other two cameras, clean them, and swap out the batteries. They also visited the larger fumarole, known as F0 and measured its temperature. This had increased about 9 °C and is now 190 °C.

Ash emission has ceased, however White Island is always capable of a new eruption at any time, without any useful warning. We continue to monitor the volcano for possible renewed activity. The Volcanic Alert Level remains at Level 1. The Aviation Colour code remains Yellow.

White Island crater area, note the missing lake

White Island crater area, note the missing lake

The active gas vent area in rear portion of crater

The active gas vent area in rear portion of crater

Agnes Mazot Duty Volcanologist

Media Contact: Brad Scott
(07 3748211)