Ruapehu volcano (North Island, New Zealand): Volcanic Alert Level lowered to Level 1; activity has decreased
Mon, 11 Jan 2021, 11:4611:46 AM | BY: MARTIN
The activity of the volcano continues at fluctuating levels during the past few months and currently continues at low levels.
Aerial view of Crater Lake at Ruapehu volcano (image: GeoNet)
GeoNet reported that gas emissions have declined to normal levels on 30 Dec last year.
On 29 Dec a volcanic tremor has decreased and remains at low levels.
Chemical analysis of water collected from Crater Lake (Te Wai ā-moe) on 31 Dec showed small changes in key parameters since previous observations a few weeks earlier on 2 Dec.
The temperature of water in Crater Lake (Te Wai ā-moe) reached a maximum of 43 °C on 21 Dec and in the last three weeks has declined to 40°C.
Approx. 200 MW (megawatt) of heat is still entering the lake and is expected to lag behind the high gas emissions observed in mid-December. A decline of lake temperature is expected.
The key parameters of the reduced unrest at the volcano are the low volcanic gas emission rate, the reduced level of volcanic tremors, and the small changes in lake water chemistry.
The Volcanic Alert Level is lowered to Level 1 and the Aviation Colour Code is lowered to Green.
Source: GeoNet New Zealand volcano activity update 11 January 2021
Mon, 28 Dec 2020, 08:27
GeoNet reported that the crater lake temperature has decreased since the last update. On 21 December the temperature reached a maximum of 43 °C that subsequently declined to approx. 41 °C. A lake temperature peak of approximately 40-46 °C is common during the heating-cooling cycles. The lake temperature exceeded 40 °C on at least 7 occasions since 2007. According to lake temperature decrease, estimated energy into the crater lake has decreased from 400 MW to 200 MW. ... Read all
Wed, 23 Dec 2020, 06:00
Ruapehu volcano (North Island, New Zealand) - Smithsonian / USGS Weekly Volcanic Activity Report for 23 December-29 December 2020 (New Activity / Unrest)
On 28 December GeoNet reported that during the previous week the temperature of Ruapehu's crater lake water slightly decreased from 43 to 41 degrees Celsius. Moderate-to-strong levels of volcanic tremor were recorded along with a small number of shallow volcanic earthquakes. The largest volcanic earthquake was an M 2.2 (on 26 December) which was uncommonly large, and combined with elevated tremor indicated ongoing unrest. ... Read all