White Island has started to show signs of new activity, including jets of gas being shot through its small lake and sediments being ejected 30 metres into the air.
"The potential for larger, more explosive eruptions that might impact on visitors to the island is always present. Any larger eruptions may occur with no warning to any visitors to the island," GNS Science said.
The aviation colour code was raised to yellow today, indicating White Island is showing signs of elevated unrest above known background levels. The volcanic alert level remains at level 1, which also indicates signs of volcanic unrest.
GNS scientists visited White Island today following an increase in volcanic tremor levels overnight and images of activity on cameras at the volcano.
Volcanologist Brad Scott said audible jets of gas were being shot through the small lake and broader expanding bubbles of dark lake sediments and debris were being ejected 20 to 30 metres into the air. The activity was similar to earlier this year.
Unrest started a year ago at White Island, leading to explosive eruptions and ash emissions last August. There was a small lava extrusion in November, followed by phreatic, steam driven activity in December which continued through January and February this year.
Small amounts of ash were emitted at times throughout the sequence.
- Fairfax Media