Group monitoring change in volcanic activity
Monday, 6 August 2012 6:30 p.m.
The Bay of Plenty Civil Defence Emergency Management Group is continuing to monitor volcanic activity in the region with the increase today in the White Island alert level from Level one to Level two.
GNS Science has raised the alert level after monitoring of the White Island web camera captured a small eruption on Sunday morning (0455h) from the Crater Lake. During the past week there has been an increase in volcanic tremor and volcanic gas levels. The Volcanic Alert Level is now raised to Level 2.
The Aviation Colour Code is changed to Orange.
These phenomena are not unknown for White Island, but this is the first substantial confirmation that small scale eruptions are now occurring on the island and confirms the risk to visitors has increased.
White Island is an active volcano and there is always risk when visiting the island and vessels travelling nearby should keep alert.
Eruptions can occur at any time with little or no warning. Extra caution should be taken if visiting the island.
Overnight Friday 27 to Saturday 28 July the lake level in the Crater Lake at White Island rose by about 3 m to 5 m. A volcanic earthquake was also recorded indicating an eruption may have occurred. A flow of gas and steam has been present through the lake and from vents near the lake since then. A gas flight on August 1 recorded increases of sulphur gases in the steam and volcanic gas plume.
Since early July there have been intermittent periods of volcanic tremor, becoming more continuous since July 28. A particularly stronger episode was recorded overnight August 4-5, and ended in a volcanic earthquake at 4.54am.
Examination of the images from the Factory webcam between 4.54am and 4.57am on 4 August have revealed an eruption from the Crater Lake.
GNS Science volcanologists are monitoring the activity and further information will be released as soon as it is available.