New Zealand - Increased likelihood of eruptions at Ruapehu; Volcanic Alert is at Level 1; Aviation Colour Code is raised to Yellow

[Pathfinder]

Volcanic Alert Bulletin RUA-2012/01 - Ruapehu Volcano

Added by Brad Scott, last edited by Brad Scott on Nov 16, 2012

16 November 2012, 10:00 am - Increased likelihood of eruptions at Ruapehu; Volcanic Alert is at Level 1; Aviation Colour Code is raised to Yellow

Recent measurements at Ruapehu indicate that the likelihood of eruptions has increased, GNS Science said today.
The Aviation Colour Code has increased from Green to Yellow, but the Volcanic Alert Level remains at 1.

GNS Science Duty Volcanologist Steven Sherburn said, ?We have been measuring changes at Ruapehu over the last few weeks and believe these changes make eruptions more likely over the next weeks to months?.

?We are monitoring Ruapehu closely, but it often does not give any immediate warning that it is going to erupt,? Dr Sherburn said.
"We think that the temperature a few hundred metres beneath Crater Lake is about 800 ?C, but the lake itself is only about 20 ?C. This suggests the vent is partly blocked which may be leading to a pressure build-up beneath Crater Lake. A sudden release of the pressure may lead to an eruption."

Since late-October small earthquakes have been occurring about 5 km
beneath the summit area of Ruapehu, but these may not be directly related to the high temperatures beneath Crater Lake as the earthquakes are much deeper.

Background
Aviation Colour Codes are based on four colours and are intended for quick reference only in the international civil aviation community. Code Yellow indicates that a volcano is experiencing signs of elevated unrest above known background levels.
The Volcanic Alert Level ranges from 0 to 5 and defines the current status at a volcano. Level 1 indicates a departure from typical background surface activity.
A build-up of pressure beneath Crater Lake is thought to have caused the 2007 eruption and a smaller eruption in 2006.

Brad Scott, Steven Sherburn
GNS Science Volcanology


http://info.geonet.org.nz/pages/viewpage.action?pageId=3801129

[Pathfinder]

Re: New Zealand - Increased likelihood of eruptions at Ruapehu; Volcanic Alert is at Level 1; Aviation Colour Code is raised to Yellow

Warning to people climbing Mt Ruapehu

Date: 16 November 2012

The Department of Conservation today issued a warning to climbers and trampers on Ruapehu, recommending that they do not enter the Summit Hazard Zone until further notice.

A Volcanic Alert Bulletin issued today by GNS Science summarising recent measurements at Ruapehu indicates the likelihood of eruptions from the mountain has increased.

The Summit Hazard Zone is the area within two kilometres of the centre of Crater Lake. It encompasses all the peaks in the summit area with Te Heuheu Peak on the north end of the summit area at the edge of the zone.

Climbers and trekkers should refer to the Summit Hazard Zone map or use their map and GPS reading skills, to determine when they are approaching the zone.

?We recommend that guiding companies do not take people into the zone. Any other climbers, trampers and walkers should not enter the zone? says Jonathon Maxwell, DOC Ruapehu Area Manager.

He said it was important to remember that Ruapehu was always active and went through periods of activity, and therefore was being constantly monitored.

The department keeps in close communications with GNS Science who continue to monitor the mountain closely. The department has also discussed the situation with Ngāti Tūwharetoa through Ngāti Hikairo ki Tongariro, Ngāti Rangi and Ngāti Uenuku, and advised Ruapehu Alpine Lifts and other concessionaires.

?We will update the warning when more information is available. Both the DOC and GeoNet websites will be kept updated,? Jonathon said.
The Eruption Detection and Lahar Warning systems operated by the department are both operational.

All facilities, roads, walking tracks, alternative routes lower on Mt Ruapehu, and other activities are fully operational within the Tongariro National Park.

People should be aware of an increased possibility of lahars on the Round the Ruapehu Mountain track people when approaching the Whangaehu, Wahianoa, Mangaturuturu and Whakapapaiti streams. They should be conscious of potential lahar noise from upstream, and make their way across these streams quickly.

Mt Tongariro and the Tongariro Alpine Crossing are not affected.

Mt Ruapehu Summit Hazard Zone

http://www.doc.govt.nz/about-doc/news/media-releases/warning-to-people-climbing-mt-ruapehu/

[Pathfinder]

Re: New Zealand - Increased likelihood of eruptions at Ruapehu; Volcanic Alert is at Level 1; Aviation Colour Code is raised to Yellow

Eruption fears rise at New Zealand's 'Mount Doom'

(AFP) ? 9 hours ago

WELLINGTON ? A New Zealand volcano that featured as Mount Doom in "The Lord of the Rings" movies is in danger of erupting as pressure builds in a subterranean vent, officials said on Monday.
...
"The current situation can't continue, Ruapehu is so active that the temperatures have been going up and down a lot," DOC volcanic risk manager Harry Keys told Radio New Zealand.

"They generally haven't gone up as we've expected for some weeks now and sooner or later that situation will be rectified, either in a small, relatively passive way, or with a significant eruption."
...
The 2,797-metre (9,177-foot) mountain last erupted in 2007, sending a lahar -- a fast-moving stream of mud and debris -- down the mountain but causing no injuries.

In 1953, a massive lahar from the mountain caused New Zealand's worst rail disaster when it washed away a bridge at Tangiwai and a passenger train plunged into the Whangaehu River, claiming 151 lives.
...

http://www.google.com/hostednews/afp/article/ALeqM5j4HY8Ll2Q9g_8pcJOBk4llf-HD4w?docId=CNG.788900529b8ada239620a92743de0f4e.671