Ruapehu Developments

 

Since early this year, the Crater Lake (Te Wai ā-moe) temperature has reduced from 32 °C to 21 °C, the GNS Science reported in their last bulletin.

This follows a continuing decline of heat flow into the lake in the range of 50-150 MW. The lake level has fluctuated in combination with episodes of snow melting and heavy rainfall and continues to flow into the Whangaehu river.

Given the ongoing weak seismic activity, both volcanic tremor and earthquakes show low values in amplitudes and numbers, respectively. Passive emissions of gas and steam continue to vent at low-to-moderate levels over the past three months.

About water samples, the most recent collection took place on 6 April, showing very small changes compared to the chemistry of samples from over the past several months. This hints that fluid movements of gas and water occur at low levels beneath the hydrothermal system.

Thus, The Volcanic Alert Level remains at 1 and the Aviation Colour Code at Green.

Source: GNS Science volcano activity update 4 May 2023