GNS Science has issued a volcanic alert for White Island because of increased activity in the crater lake and numerous earthquakes. GNS Science duty volcanologist Michael Rosenberg says the risk of eruption has increased. “Eruptions can occur at any time with little or no warning. The recent changes in activity suggest that the hydrothermal system has become unstable, and as a result the risk has increased.” The aviation colour code has been changed from green to yellow, meaning the volcano “is experiencing signs of elevated unrest above known background levels”. The volcanic alert level remains at 1 – “departure from typical background surface activity”. There have been a number of earthquakes in the vicinity of the island since the beginning of July. Mr Rosenberg says until very recently the crater lake was almost empty, but between Friday July 27 and Saturday July 28 the level rose by about 3m to 5m. A recent ground survey has also showed the main crater floor may be slowly rising. “These phenomena are typical for White Island’s activity, but are the first substantial changes to occur in the last few years,” Mr Rosenberg says. The amount of sulphur gas being emitted from the volcano has also increased. But Mr Rosenberg says the crater lake has not been accessible for some months and GNS Science has been unable to measure temperature or chemistry changes. Mr Rosenberg warns people that White Island is an active volcano and people visiting the island need to take extra care. He says the activity at the island has no connection to the recent earthquakes and changes in gas flux at Mt Tongariro. GNS Science isVol monitoring the situation and will release more information as it becomes available. White Island is located 48km off the east coast of the North Island in the Bay of Plenty.
- RSOE Edis
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