Pathfinder
Editor, Senior Moderator
Apr 5 2011 - Ruapehu Volcano
Volcanic Alert Bulletin RUA-2011/02 - Crater Lake remains hot; Aviation Colour Code changed to Yellow; Alert Level remains at 1
Mount Ruapehu is currently experiencing a sustained period of high water temperatures in the Crater Lake (currently about 38 - 39 ?C). In recent weeks changes have also occurred in volcanic gas output, seismic activity and Crater Lake water chemistry. These changes show that Ruapehu is experiencing signs of elevated unrest above known background levels, hence the Aviation Colour Code is being raised to Yellow. The Volcanic Alert Level remains at Level 1 (signs of volcanic unrest).
The current heating cycle of the Crater Lake, which started in October 2010, has continued. The temperature of the lake peaked at 41 ?C on 1 March and is currently fluctuating around 38 - 39 ?C. Since the lake was re-established in 2002, the highest recorded temperature was 42.5 ?C in May 2003, and there have been eight heating cycles. The temperature of Crater Lake is a measure of the amount of volcanic heat coming from Ruapehu.
During the current period of high lake temperatures there have also been changes in lake chemistry, increases in carbon dioxide gas emissions and minor increases in seismic activity beneath the volcano. These observations, particularly the seismic activity, have not been observed during previous periods of high lake temperature.
These observations indicate that Ruapehu is experiencing a period of unrest above that which is typical. At times steam may be seen above Crater Lake and sediments on the lake floor may be disturbed by gas and heat flow causing the lake to change colour. However, there are currently no indications that an eruption is imminent.
The elevated unrest is sufficient to raise the Aviation Colour Code to Yellow. This is used only by international aviation. The Volcanic Alert Level is at Level 1 and this already reflects the current state of unrest.
GNS Science volcanologists continue to monitoring Ruapehu. Ruapehu remains an active volcano and future eruptions may occur with little or no warning.
The Volcanic Alert Level remains at Level 1 (departure from typical background surface activity, signs of unrest). The Volcanic Aviation Colour Code is raised to Yellow (elevated unrest above the known background).
Agnes Mazot
GeoNet Duty Volcanologist
For further information, please contact:
Brad Scott
Volcano Surveillance Coordinator
Steve Sherburn
Volcano Seismologist
http://www.geonet.org.nz/volcano/al...lert-bulletin-apr-5-2011-ruapehu-volcano.html
Volcanic Alert Bulletin RUA-2011/02 - Crater Lake remains hot; Aviation Colour Code changed to Yellow; Alert Level remains at 1
Mount Ruapehu is currently experiencing a sustained period of high water temperatures in the Crater Lake (currently about 38 - 39 ?C). In recent weeks changes have also occurred in volcanic gas output, seismic activity and Crater Lake water chemistry. These changes show that Ruapehu is experiencing signs of elevated unrest above known background levels, hence the Aviation Colour Code is being raised to Yellow. The Volcanic Alert Level remains at Level 1 (signs of volcanic unrest).
The current heating cycle of the Crater Lake, which started in October 2010, has continued. The temperature of the lake peaked at 41 ?C on 1 March and is currently fluctuating around 38 - 39 ?C. Since the lake was re-established in 2002, the highest recorded temperature was 42.5 ?C in May 2003, and there have been eight heating cycles. The temperature of Crater Lake is a measure of the amount of volcanic heat coming from Ruapehu.
During the current period of high lake temperatures there have also been changes in lake chemistry, increases in carbon dioxide gas emissions and minor increases in seismic activity beneath the volcano. These observations, particularly the seismic activity, have not been observed during previous periods of high lake temperature.
These observations indicate that Ruapehu is experiencing a period of unrest above that which is typical. At times steam may be seen above Crater Lake and sediments on the lake floor may be disturbed by gas and heat flow causing the lake to change colour. However, there are currently no indications that an eruption is imminent.
The elevated unrest is sufficient to raise the Aviation Colour Code to Yellow. This is used only by international aviation. The Volcanic Alert Level is at Level 1 and this already reflects the current state of unrest.
GNS Science volcanologists continue to monitoring Ruapehu. Ruapehu remains an active volcano and future eruptions may occur with little or no warning.
The Volcanic Alert Level remains at Level 1 (departure from typical background surface activity, signs of unrest). The Volcanic Aviation Colour Code is raised to Yellow (elevated unrest above the known background).
Agnes Mazot
GeoNet Duty Volcanologist
For further information, please contact:
Brad Scott
Volcano Surveillance Coordinator
Steve Sherburn
Volcano Seismologist
http://www.geonet.org.nz/volcano/al...lert-bulletin-apr-5-2011-ruapehu-volcano.html
