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Re: THE Volcano Thread Pt. 2

Unread postPosted: Thu 12 Oct 2017, 14:26:54
by dohboi
Yellowstone supervolcano may blow sooner than thought — and could wipe out life on the planet

Scientists working in and around Yellowstone National Park say that the supervolcano sitting under the tourist attraction may blow sooner than thought, an eruption that could wipe out life on the planet.

According to National Geographic, the researchers, from Arizona State University, analyzed minerals in fossilized ash from the most recent mega-eruption and found changes in temperature and composition that had only taken a few decades. Until now, the magazine reported, geologists had thought it would take centuries for the supervolcano to make the transition. ...


https://amp.usatoday.com/story/757337001/

And some of the latest from Agung here, though if anyone has better sources at hand, please do share:

https://www.thesun.co.uk/news/4547829/b ... el-latest/

Re: THE Volcano Thread Pt. 2

Unread postPosted: Tue 21 Nov 2017, 12:47:26
by dohboi

Öræfajökull observed from space

Unread postPosted: Tue 21 Nov 2017, 14:55:09
by dolanbaker
Öræfajökull is another one to keep an eye on, but volcanic activity is nothing out of the ordinary in Iceland.


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http://icelandmonitor.mbl.is/news/natur ... rom_space/
The European Space Agency (ESA) satellite called SENITEL -1 has been photographing the surface of Öræfajökull from space and in the images, developments are clearly visible.

According to a short report on the Facebook page of the volcano and natural hazard department of the University of Iceland the images show that there were no cracks in the cauldera in Öræfajökull at the end of October.

However, on November 8th there were clear changes and obvious cracks in the middle of the cauldera. These cracks are even larger in images taken yesterday, November 20th.

Image showing the icecap cracking due to the volcanic activity below.
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Re: THE Volcano Thread Pt. 2

Unread postPosted: Tue 21 Nov 2017, 15:05:13
by dohboi
Wow, thanks for the update, dol. Hadn't heard of that one.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Tue 21 Nov 2017, 15:17:39
by dolanbaker
This is a useful site to watch volcanic activity in Iceland http://en.vedur.is/earthquakes-and-volc ... arthquakes
This type of activity is so common that it is combined with the weather.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 25 Nov 2017, 11:51:18
by vox_mundi
Climate Change Could Increase Volcano Eruptions

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Shrinking glacier cover could lead to increased volcanic activity in Iceland, warn scientists.

Dr Graeme Swindles, from the School of Geography at Leeds, said: "Climate change caused by humans is creating rapid ice melt in volcanically active regions. In Iceland, this has put us on a path to more frequent volcanic eruptions."

The study examined Icelandic volcanic ash preserved in peat deposits and lake sediments and identified a period of significantly reduced volcanic activity between 5,500 and 4,500 years ago. This period came after a major decrease in global temperature, which caused glacier growth in Iceland.

Dr Swindles said: "The human effect on global warming makes it difficult to predict how long the time lag will be but the trends of the past show us more eruptions in Iceland can be expected in the future.

Study co-author, Dr Ivan Savov, from the School of Earth & Environment at Leeds, explains: "When glaciers retreat there is less pressure on the Earth's surface. This can increase the amount of mantle melt as well as affect magma flow and how much magma the crust can hold.

"Even small changes in surface pressure can alter the likelihood of eruptions at ice-covered volcanos."

Open Access: Graeme T. Swindles et al. Climatic control on Icelandic volcanic activity during the mid-Holocene, Geology (2017).

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Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 25 Nov 2017, 12:37:49
by Subjectivist
Any increase from isostatic rebound would be a very temporary conditin, not a permanent change. All glacier weight does is increase the pressure needed for the magma to break through to the surface. Take away the extra weight and a series of eruptions will relieve the extra presssure, then things return to the long term average time between build ups and eruptions a the lower pressure level.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 25 Nov 2017, 13:01:13
by dohboi
But in the mean time, it is yet another feedback...

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 25 Nov 2017, 13:10:37
by rockdoc123
The plot showing average number of volcanoes per decade is misleading for two reasons, 1. the vast majority of volcanic eruptions during this period are nowhere near an ice sheet and 2. the plot is more a measure of communication increase given there could have been lots of volcanic eruptions at the start of this time cycle that were not reported.

Periods of increased vulcanism are generally associated with change in tectonic plate motion, faster spreading rates can mean increased melt in subduction zones followed by increased upwelling and resultant vulcanism.

Something else that is incorrect here is that removing ice results in isostatic rebound so crustal rocks that were at a depth where partial melt occurs would now be at a level where partial melt is no longer occurring in effect stabilizing rock surrounding any mantle plume. Overburden pressure is less of a controlling factor than the presence of an expanding magma chamber where generated pressures are magnitudes higher than overburden pressure. As Sub points out any pressure imbalance caused by the removal of ice would be short lived with equilibrium occurring almost immediately.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Thu 30 Nov 2017, 18:46:46
by dohboi
More context:

Could Mount Agung cause global cooling effects lasting for years?


https://www.accuweather.com/en/weather- ... s/70003412

How could the Agung volcano in Bali affect global temperatures?

https://www.skepticalscience.com/how-co ... temps.html

Further:

Agung's recent activity matches the build-up to the earlier disaster, which ejected enough debris - about a billion tonnes - to lower global average temperatures by around 0.3°C for roughly a year.


http://www.channelnewsasia.com/news/asi ... ok-9454396

(Prepare for ignorant howls from the denialoosphere that 'GW is Over (and was hoax anyway)...blah, blah, blah')

Re: THE Volcano Thread Pt. 2

Unread postPosted: Thu 07 Dec 2017, 12:31:15
by vox_mundi
Dangerous Iceland Volcano Oraefajokull May Be About to Erupt for First Time Since 1728

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The Oraefajokull (err-IVER'-yer-kuhl) volcano, dormant since its last eruption in 1727-1728, has seen a recent increase in seismic activity and geothermal water leakage that has worried scientists. With the snow hole on Iceland's highest peak deepening 18 inches (45 centimeters) each day, authorities have raised the volcano's alert safety code to yellow.

Experts at Iceland's Meteorological Office have detected 160 earthquakes in the region in the past week alone as they step up their monitoring of the volcano. The earthquakes are mostly small but their sheer number is exceptionally high.

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http://en.vedur.is/about-imo/news/monit ... aefajokull
Volcanologist Ármann Höskuldsson says that the situation at Öræfajökull volcano is "Far from normal." There's still geothermal heat in the area and the caldera has deepened by some 20 metres.

A 3-D image made by specialists at the Geological Institute of the University of Iceland indicates that the caldera has deepened by twenty metres and that crevasses have become larger since it was first spotted.


Öræfajökull hasn‘t erupted for nearly 300 years, but recent weeks have shown increased activity in the area. A new caldera emerged in the glacier nearly two weeks ago.

In 1362, the volcano erupted explosively, with huge amounts of tephra being ejected. The district of Litla-Hérað was destroyed by floods and tephra fall. More than 40 years passed before people again settled the area, which became known as Öræfi. The name literally means an area without harbor, but it took on a meaning of wasteland in Icelandic.

What worries scientists the most is the devastating potential impact of an eruption at Oraefajokull.

Located in southeast Iceland about 320 kilometers (200 miles) from the capital, Reykjavik, the volcano lies under the Vatnajokull glacier, the largest glacier in Europe. Its 1362 eruption was the most explosive since the island was populated, even more explosive that the eruption of Italy's Mount Vesuvius in 79 A.D. that destroyed the city of Pompei.

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Oraefajokull at lower center, near coast

To remedy the lack of data for Oraefajokull, scientists are rushing to install new equipment on and around the volcano. Those include ultra-sensitive GPS sensors that can detect even the slightest tremors, webcams for real-time imagery of the volcano and sensors in the rivers that drain the volcano's glaciers to measure the chemical composition of the water.

Associated Press journalists last week visited scientists working near the mouth of the Kvia River, where the stench of sulfur was strong and the water was murky, clear signs that geothermal water was draining from the caldera.

... If an evacuation is ordered, everyone in the area will receive a text message and the radio will broadcast updates. Police are confident that Oraefi's 200 residents will know how to react, but their biggest concern is contacting tourists.
"Some farmers may have only 20 minutes (to leave)"

"The locals know what to do. They know every plan and how to react. But the tourists, they don't," said Police Chief superintendent Sveinn Runarsson. "That's our worst nightmare."

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 12 Jan 2018, 16:34:35
by dohboi
The activity of #Agung is still high. Eruption on 11 January.
https://twitter.com/janinekrippner/stat ... 4986594304

Re: THE Volcano Thread Pt. 2

Unread postPosted: Mon 15 Jan 2018, 09:12:39
by dohboi
http://www.cnn.com/2018/01/15/asia/mayo ... index.html

Philippines on high alert as volcano might erupt in 'weeks or days'

Re: THE Volcano Thread Pt. 2

Unread postPosted: Wed 17 Jan 2018, 00:23:45
by dohboi
Video of lava flow...thousands evacuated

http://www.cnn.com/videos/world/2018/01 ... rig-bk.cnn

Re: THE Volcano Thread Pt. 2

Unread postPosted: Wed 17 Jan 2018, 07:44:25
by dohboi
More video's and pictures: http://www.businessinsider.com/philippi ... yon-2018-1

I love this term: "State of Calamity Declared..."

http://www.straitstimes.com/asia/se-asi ... o-eruption

(Someone needs to declare that the White House is in a 'State of Calamity'! 8)

Re: THE Volcano Thread Pt. 2

Unread postPosted: Fri 26 Jan 2018, 14:30:24
by dohboi
Nearly 100,000 now evacuated from the area around Mt. Mayon!

https://watchers.news/2018/01/26/81-618 ... ilippines/

Re: THE Volcano Thread Pt. 2

Unread postPosted: Sat 27 Jan 2018, 18:23:49
by Outcast_Searcher
dohboi wrote:More video's and pictures: http://www.businessinsider.com/philippi ... yon-2018-1

I love this term: "State of Calamity Declared..."

http://www.straitstimes.com/asia/se-asi ... o-eruption

(Someone needs to declare that the White House is in a 'State of Calamity'! 8)

The NYT does this scores of times a week. Of course, they would support dome of the "calamities" if a dem were in the WH, so there's that.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Tue 20 Feb 2018, 11:25:47
by dohboi

Re: THE Volcano Thread Pt. 2

Unread postPosted: Tue 20 Feb 2018, 12:38:33
by ROCKMAN
dohboi - Heard an interesting fact on a BBC special about the oceans. While we occasionally focus on the atmospheric effects of onshore volcanos it turns out the 75% of all active volcanos sit on the bottom of the oceans. Combined with human effects you have to wonder what those eruptions are having on the ocean's chemistry.

Re: THE Volcano Thread Pt. 2

Unread postPosted: Thu 22 Feb 2018, 00:32:44
by dohboi
Well, probably about the same effect they've been having since as long as they've been there, unless you have evidence that there has been some increase in their activity recently.