Mt Ruapehu - elevated unrest

[Lovelee]

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).

http://www.geonet.org.nz/volcano/alert-bulletins/archives/2011/alert-bulletin-apr-5-2011-ruapehu-volcano.html?utm_source=twitterfeed&utm_medium=twitter&utm_campaign=twitter_News

[nitpicker1]

that's all we need to focus attention on a different subject


meanwhile see attachment   

[Lovelee]

Well DT was talking about things coming in 3's 

[dragontamer]

That can jolly well settle down.  My favourite brother lives in Horopito.  I've seen those boulders its spat out all over his yard.

[Lovelee]

Increased rumblings under Mt Ruapehu and a warmer-than-usual crater lake have led authorities to raise alert levels for planes flying over the area.

A volcanic eruption is not imminent - the alert level remains at one out of five - but volcanologists say there are subtle signs of unrest under Ruapehu, which last erupted in 2007.

An aviation warning level introduced in November has been raised for the first time to yellow - the second-lowest on a four-tier system. The alert is a precaution, as few international flights travel near Ruapehu.

GNS Science volcano surveillance co-ordinator Brad Scott said water temperature in the lake yesterday was higher than background levels, at about 39C.

"The crater lake is a fairly big puddle and if you can heat that up to 40C, it takes a fair bit of energy."

On March 1, it reached 41C, just 1.5C off the highest temperature since the lake was re-established in 2002.

As well, GNS observed changes in the lake's chemistry with greater amounts of magnesium detected. This suggests water in the lake has come into contact with fresh surfaces of molten rock.

Higher levels of carbon dioxide measured in the lake also point to molten material under the volcano.

The frequency of seismic activity 6km under the volcano has increased since December. Mr Scott said 12 small quakes had been detected this year, about three times more than normal.

The volcanic warning level would only be raised if there were large shifts in several indicator areas or if small-scale eruptions occurred, Mr Scott said.

"There's no one trigger; it's usually a combination of things such as big changes in deformation, chemistry, heat flow and earthquakes."

Ruapehu's 2007 eruption lasted for seven minutes and caused two lahars, one of which spilt into the Whakapapa skifield. It also produced a column of ash and a rockfall which seriously injured one person.

It is an active volcano, meaning eruptions can occur with little or no warning.

The only other volcano in New Zealand on alert level one is White Island.

http://www.weatherwatch.co.nz/content/rumblings-ruapehu-spark-alert-planes?utm_source=twitterfeed&utm_medium=twitter

[Lovelee]

Volcanic Alert Bulletin RUA-2011/03 - Crater Lake slowly cooling; Aviation Colour Code remains at Yellow; Alert Level remains at 1.

The temperature of the Crater Lake has decreased to around 33-34°C from a peak of 41°C in March 2011. Other monitored indicators in recent weeks also suggest a slow decrease of activity.

While activity seems to be decreasing overall, and there are no data to suggest an imminent eruption, the volcano remains in a state of elevated unrest above the typical background level. Therefore, the Aviation Colour Code remains at Yellow and the Volcanic Alert Level remains at Level 1.

The current heating phase of the Crater Lake, which started in October 2010, appears to be declining. The temperature of the lake peaked at 41°C on March 1 and fluctuated around 38-39°C during that month. Over the past two weeks, the Crater Lake temperature has decreased and is now fluctuating around 33-34°C.

Since April 4, observations by GNS Science show a general decrease in activity, with lower CO2 gas flux, less seismicity, little change in the Crater Lake water chemistry and cessation of lake overflow accompanying the start of the cooling trend.

Despite the reduced activity Ruapehu remains at a slightly elevated level of unrest and the Aviation Colour Code therefore remains at Yellow.

If atmospheric conditions are suitable, steam may still be seen above the crater and, if lake sediments on the lake floor are disturbed by the gas and\ heat flow into the lake, the lake colour may change.

GNS Science volcanologists continue to monitoring this and other volcanoes. Ruapehu remains an active volcano and future eruptions may occur with little or no warning.

http://www.geonet.org.nz/volcano/alert-bulletins/archives/2011/alert-bulletin-apr-18-2011-ruapehu-volcano.html?utm_source=twitterfeed&utm_medium=twitter&utm_campaign=twitter_News

[Lovelee]

The Aviation Colour Code for Ruapehu has been returned to Green, the lowest code. The temperature of the Crater Lake has continued to decrease and is now around 30 °C, down from a recent peak of 41 °C in March. Other available monitored indicators also suggest a slow decrease of activity in recent weeks.

The volcano is no longer considered in a state of elevated unrest, therefore the Aviation Colour Code has been returned to Green; the Volcanic Alert Level remains at Level 1.

The temperature of the Crater Lake, which started to rise in October 2010, is now declining. The temperature of the lake peaked at 41 °C on March 1 and fluctuated around 38 - 39 °C during March. Over the past two weeks, the Crater Lake temperature has continued to decrease and is now around 30 °C.

The Crater Lake temperature has been declining steadily since late March, the lake has remained below overflow, and no earthquakes have been located within 10 km of the Crater Lake for two weeks. This indicates a reduced level of activity at Ruapehu and the volcano is no longer considered to be showing slightly elevated unrest. The Aviation Colour Code therefore is reduced from Yellow to Green.

GNS Science volcanologists continue to monitor this and other volcanoes. 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 changed from Yellow to Green (volcano is in normal, non-eruptive state)

Brad Scott
Duty Volcanologist

http://www.geonet.org.nz/volcano/alert-bulletins/archives/2011/alert-bulletin-may-2-2011-3-00-pm-ruapehu-volcano.html?utm_source=twitterfeed&utm_medium=twitter&utm_campaign=twitter_News

[Lovelee]

9 April 2013, 1:30pm - Crater Lake starts heating; Volcanic Alert remains at Level 1; Aviation Colour Code remains Green.
The temperature of Crater Lake has started to rise and has now reached 30°C. It has been accompanied by some minor volcanic tremor. The chemistry data from our last sampling trip confirms the decline of temperature in the deep geothermal system.

Volcanologist Brad Scott said these data indicate the Crater Lake is returning to a more typical state, where heat and gas flow from depth is entering the lake. The anomaly of higher heat at depth and cooler temperatures in the lake appears to have passed. However the volcano remains in unrest and eruptions could still occur with no warning.

Background
The Volcanic Alert Level for Ruapehu remains at Level 1, indicating a departure from typical background, signs of unrest. The Volcanic Alert Level ranges from 0 to 5 and defines the current status at a volcano.

The Aviation Colour Code for Ruapehu is Green. Aviation Colour Codes are based on four colours and are intended for reference only in the international civil aviation community.

Brad Scott
Volcanologist

[Kiwithrottlejockey]

from Fairfax NZ....

Ruapehu crater lake heats up

Scientists unsure if Ruapehu will stick to tradition and
erupt following the volcano's latest earthquake swarm.

1:44PM - Saturday, 30 April 2016


The water temperature of Mount Ruapehu's crater lake has risen from 25 degrees celsius
to 40 degrees since mid-April.

SCIENTISTS are unsure if recent earthquake swarms recorded underneath Mount Ruapehu are a sign of something bigger to come.

Geonet issued a volcanic alert on Friday, saying the crater lake temperature had climbed to 40 degrees Celsius, up from 25°C in mid-April.

Duty volcanologist Agnes Mazot​ said since April 26th, a “volcanic earthquake swarm” had been recorded beneath the crater lake.

Such earthquake swarms are uncommon on Ruapehu and scientists were uncertain of the implications of the activity.

Seismic activity at Mount Ruapehu is typically dominated by volcanic tremors.

Rises in water temperature of the crater lake were observed in March 2011, April 2014, and February 2015.

Mazot said Geonet monitoring had not recorded any changes in other parameters such as volcanic gas, lake overflow and lake chemistry.

He said the changes at Ruapehu were not considered sufficient to change the Volcanic Alert Level, which currently sat at level 1.

The changes at Mount Ruapehu were not related to the volcanic eruption at White Island on April 27th, Mazot said.

Staff would continue to monitor Ruapehu closely.

http://www.stuff.co.nz/environment/79476949

[ssweetpea]

Mr Sp was down that way on the weekend. There is no snow on any of the peaks. Zilch and it is May.

Ruapehu looks weird without snow.