Recent observations and gas flights show continuing steam and gas plumes from the normal cluster of active vent locations on the west shore of the lake. Minor erosion continues to make small changes to the area. Measured gas discharge rates have remained within normal ranges over the last few months. Views from the Whakatāne webcam support these observations, although local atmospheric conditions can sometimes allow tall steam plumes to develop above the island. The regular aerial views of the islands confirm steam and gas vents in the crater have shown no evidence of ash emission or eruptive activity.
Measurements from regular observation flights have recorded a decline in the temperatures from the larger vents. In March, temperatures were higher than 240 °C, in June-August 120 to 123 °C, and now in October, they are 95 °C.
During the 4th of October observation flight, a rock fall was observed happening from Troup Head on the eastern end of the island. The fall propagated to the ridge crest, and rocks fell to both the southern and northern sides of the ridge. Although unusual, there is evidence of past rock falls in this area.
The volcano is being monitored by the near-real-time GNS webcam as well as by satellites from space. Satellite-based ground deformation data, retrieved approximately every 10 days, allow to observe long-term ground deformation trends. Daily satellite-based sulfur dioxide (SO2) emission measurements using TROPOMI, although not as sensitive as GNS gas measurement flights. Neither of these satellite techniques has detected significant changes in the overall activity at the volcano over the past few months.
Both alert levels, the Aviation Color Code and the Volcanic Alert Level remain at Yellow and Level 2.
Source: GeoNet New Zealand volcano activity update 10 October 2023