Posted on 04/03/2008 5:30:58 PM PDT by blam
Melting ice caps may trigger more volcanic eruptions
10:38 03 April 2008
NewScientist.com news service
Catherine Brahic
Vatnajökull in the south-east is the largest ice cap in Iceland and conceals several volcanoes (Image: NASA)
A warmer world could be a more explosive one. Global warming is having a much more profound effect than just melting ice caps – it is melting magma too.
Vatnajökull is the largest ice cap in Iceland, and is disappearing at a rate of 5 cubic kilometres per year.
Carolina Pagli of the University of Leeds, UK, and Freysteinn Sigmundsson of the University of Iceland have calculated the effects of the melting on the crust and magma underneath.
They say that, as the ice disappears, it relieves the pressure exerted on the rocks deep under the ice sheet, increasing the rate at which it melts into magma. An average of 1.4 cubic kilometres has been produced every century since 1890, a 10% increase on the background rate.
Frequent eruptions
In Iceland there are several active volcanoes under the ice. The last big eruption was in 1996 at Gjàlp, and before then in 1938 – a gap of 58 years. But Pagli and Sigmundsson say that the extra magma produced as the ice cap melts could supply enough magma for similar eruptions to take place every 30 years on average.
Predicting the eruptions precisely will be tricky, though, as the rate of magma migration to the surface is unknown.
The situation in Iceland does not necessarily mean magma will be melting faster around the world. Vatnajökull sits atop a boundary between plates in the Earth's crust, and it is this configuration that is allowing the release in pressure to have such a great effect deep in the mantle.
(Excerpt) Read more at environment.newscientist.com ...
FYI
...and they may not.
How many centuries has that been?
Fear, Uncertainty and Doubt at its finest!
I need help. That photo of iceland, is the white stuff the ice and/or snow, and the green stuff being land not covered in ice or snow?
Global warming is increasing magma? Lunatic.
Sigh, 28 miles of pipe, and we can refill the dead sea, before the caldera erupts.
That is absurd. From what I've read about the supposed Global Warming, the average temps have gone up about 0.5°C or so and that is "melting magma"? Isn't magma already melted, as in molten lava? A quick internet search told me that the temperatures of most magma are 600°C to 1300°C. So, we carbon based lifeforms are "melting magma" by driving SUVs and using incandescent light bulbs??? Yeah, sure we are.
And this will continue to occur unless you pay me 1 MILLION dollars!
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"We could die any second, Anna! I'm afraid we won't live through this. Please, Anna, one date! Hey, where are you going? Don't walk away like that . . ." |
Gotta love it! Magma IS melted rock already! How does something that is melted already become MORE melted?
/GEEEEZ !
Is there anything global warming can’t do?
The global communism crowd is like liberals here,turn everything around to fit some kooky scheme,Iceland and Greenland,artic sea,anartica are all volcanic areas that are active and are melting the ice. They will blame anything that happens or may happen and even though it won’t happen still say it will happen to get what they want,,,control of everything,,the grand prize,,what it’s always been about since the beginning,,control of the world! Their thinking is “ we are too stupid to be free,,they will give us structure and restaint and happiness.” We will be happy little serfs! wow!
Which makes a lot of sense inasmuch as this happens in Eastern Lake Superior (couple of volcanoes there) every time we get an "interglacial" in the current ongoing 2 million year old Ice Age.
However, it can also be the case that an existing volcano tokes up (e.g. Iceland is a volcanic piece of the Mid-Atlantic Ridge, so it's volcanoes turn on and off all the time ~ geologically speaking). When the volcano tokes up, it heats up, and melts the ice. People say "Whoa, is that melting ice because it's warmer air, or is that melting ice because it's warmer ground?"
At the moment, to be fashionable, the Icelanders regularly interpret every irregularity in their homeland as being derived from GW.
Which makes a lot of sense inasmuch as this happens in Eastern Lake Superior (couple of volcanoes there) every time we get an "interglacial" in the current ongoing 2 million year old Ice Age.
However, it can also be the case that an existing volcano tokes up (e.g. Iceland is a volcanic piece of the Mid-Atlantic Ridge, so it's volcanoes turn on and off all the time ~ geologically speaking). When the volcano tokes up, it heats up, and melts the ice. People say "Whoa, is that melting ice because it's warmer air, or is that melting ice because it's warmer ground?"
At the moment, to be fashionable, the Icelanders regularly interpret every irregularity in their homeland as being derived from GW.
But if they do, guess what, it’s another negative feedback mechanism omitted from all the climate models, since, as we know from experience, volcanic eruptions cool the earth by disbursing ash into the upper atmosphere (cf. Tambura and the ‘year without a summer’ in 1816).
I’m starting to think climate modeling should be turned over to Shakespeare scholars: “There are more things in heaven and earth than are dreamt of in your philosophy. . .”
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