Volcanic Alert Bulletin WI-2013/10 - White Island Volcano

Over the weekend the style of activity at White Island changed: the active vent began producing ash. The island was visited today and the ash emission has ceased, being replaced by steam and gas explosions from the active vent.

The level of volcanic tremor has increased, associated with the reappearance of fluids in the vent area. This change in activity is consistent with the level of unrest we have seen over the last month at the island.

The current episode of activity started in August 2012 (explosions and ash emission) followed in November 2012 by the extrusion of a small lava dome. Elevated but not high unrest followed. Volcanic unrest again increased at White Island in mid-January and continues. This unrest has been manifested as increased hydrothermal activity in the ‘hot lake’ which has now developed into an active vent area. This is some of the most vigorous activity seen at White Island for many years.

GNS volcanologist Brad Scott who visited the island today commented “the unrest continues and we continue to see small scale explosive events. Larger explosive eruptions can occur at any time with little or no warning. As always a high level of caution should be taken if visiting the island”.

The outcome of the unrest remains unclear; it could lead to explosive eruptions and ash emissions, like in August 2012 or decline away. The state of unrest at White Island is relatively static at present, with no clear signs of an increase or decrease in activity.

Background

Aviation Colour Codes are based on four colours and are intended for quick reference only in the international civil aviation community.

The Volcanic Alert Level ranges from 0 to 5 and defines the current status at a volcano. Level 2 indicates minor eruptive activity.

Brad Scott
Volcanologist