Mr Scott’s observations confirmed that hydrothermal activity in the small 'hot lake' has increased. The most common activity is "doming-up" of the lake surface by steam/gas, bringing large amounts of sediment to the surface, often with vivid white steam/gas 'flashing' from around the base. Every so often stronger events happened. This activity has been increasing since late 2012 and is now semi-continuous. GNS volcanologist Brad Scott said “the hydrothermal activity is some of the most vigorous I have seen at White Island for many years. This type of activity usually leads to stronger volcanic activity and is a significant concern.” The lava dome that was first observed in late November has not changed since the last observations on 1 January 2013. Seismicity continues to show elevated levels of volcanic tremor and this is likely to be generated by the processes driving the vigorous hydrothermal activity in the lake. The state of unrest at White Island is increasing and future eruptions are possible with little or no warning. The increased level of unrest does mean that there is a hazard to visitors. Past activity indicates that eruptions, such as that which occurred on 5 August 2012, could occur with little or no warning, even when the Alert Level is 1 (volcanic unrest). Caution should be exercised when visiting the island. GNS Science continues to closely monitor White Island through the GeoNet project.

White Island Hydrothermal Activity January 2013

Filmed by Brad Scott of GNS Science, on a routine volcano monitoring trip to White Island

Background The Volcanic Alert Level ranges from 0 to 5 and defines the current status at a volcano. Level 1 indicates signs of volcanic unrest. Aviation Colour Codes are based on four colours and are intended for quick reference only in the international civil aviation community.

Brad Scott Duty Volcanologist