Mar 6 2007, 4:00 pm - White Island Volcano

A recent visit to White Island on 23 February, found that the level of the Crater Lake had fallen by 1.2 metres in 10 days. The rate of fall is increasing, and the lake is now 9 metres below the overflow level. This shows the effect of rapid evaporation, with the lake temperature again measured at 74ºC. The falling level has reduced the area of the lake by about 10%, and volume by 20%, which means that even at the same heat flow, the lake volume can be expected to decrease more rapidly.

No changes have been observed that would indicate an increase in volcanic activity, but the water level fall will change the pressures in the geothermal system and this may become unstable and result in local boiling events at depth in the lake. These may produce transient steam plumes that rise above the island.

The Alert Level for White Island remains at Alert Level 1; there is no significant change in volcanic activity on the island.

Tony Hurst
Geohazards Duty Officer