Modeled basal ice temperatures of the present-day Greenland Ice Shield across the Summit region, GRIP and GISP2 indicate borehole locations. Credit: A. Petrunin/GFZ Posted on 08/13/2013 10:46:43 AM PDT by Red Badger
Modeled basal ice temperatures of the present-day Greenland Ice Shield across the Summit region, GRIP and GISP2 indicate borehole locations. Credit: A. Petrunin/GFZ
The Greenland ice sheet is melting from below, caused by a high heat flow from the mantle into the lithosphere. This influence is very variable spatially and has its origin in an exceptionally thin lithosphere. Consequently, there is an increased heat flow from the mantle and a complex interplay between this geothermal heating and the Greenland ice sheet. The international research initiative IceGeoHeat led by the GFZ German Research Centre for Geosciences establishes in the current online issue of Nature Geoscience (Vol 6, August 11, 2013) that this effect cannot be neglected when modeling the ice sheet as part of a climate study.
The continental ice sheets play a central role in climate. Interactions and feedback processes between ice and temperature rise are complex and still a current research topic. The Greenland ice sheet loses about 227 gigatonnes of ice per year and contributes about 0.7 millimeters to the currently observed mean sea level change of about 3 mm per year. Existing model calculations, however, were based on a consideration of the ice cap and considered the effect of the lithosphere, i.e. the earth's crust and upper mantle, too simplistic and primarily mechanical: the ice presses the crust down due to its weight. GFZ scientists Alexey Petrunin and Irina Rogozhina have now coupled an ice/climate model with a thermo-mechanical model for the Greenland lithosphere. "We have run the model over a simulated period of three million years, and taken into account measurements from ice cores and independent magnetic and seismic data", says Petrunin. "Our model calculations are in good agreement with the measurements. Both the thickness of the ice sheet as well as the temperature at its base are depicted very accurately. "
The model can even explain the difference in temperature measured at two adjacent drill holes: the thickness of the Greenland lithosphere and thus the geothermal heat flow varies greatly in narrow confines.
What does this mean for climate modeling? "The temperature at the base of the ice, and therefore the current dynamics of the Greenland ice sheet is the result of the interaction between the heat flow from the earth's interior and the temperature changes associated with glacial cycles," explains corresponding author Irina Rogozhina (GFZ) who initiated IceGeoHeat. "We found areas where the ice melts at the base next to other areas where the base is extremely cold."
The current climate is influenced by processes that go far back into the history of Earth: the Greenland lithosphere is 2.8 to 1.7 billion years old and is only about 70 to 80 kilometers thick under Central Greenland. It remains to be explored why it is so exceptionally thin. It turns out, however, that the coupling of models of ice dynamics with thermo-mechanical models of the solid earth allows a more accurate view of the processes that are melting the Greenland ice.
AGW Ping!................
Now they have to figure out how to connect human beings to the heat of the Earth’s mantle.
It is still the sun....
Heat in the core of the earth is from Radioactive decay...
The sun can affect radioactive decay: http://wavewatching.net/2012/09/01/from-the-annals-of-the-impossible-experimental-physics-edition/
OMG the sun is causing greenland to melt......
I say it’s a byproduct of all those progressives roasting in Hell, but it’s just a theory. If the government would send some research grant money my way I’d be happy to study it for a few years.
In other words, it's hot near the fire.
/johnny
O'BRIEN: ...to create energy, and it sounds to me like an evil plan by Lex Luthor to defeat Superman. Can you, can you tell me, is this a viable solution, geothermal energy?GORE: It definitely is, and it's a relatively new one. People think about geothermal energy - when they think about it at all - in terms of the hot water bubbling up in some places, but two kilometers or so down in most places there are these incredibly hot rocks, 'cause the interior of the earth is extremely hot, several million degrees, and the crust of the earth is hot ...
Bet even he hurt himself when he pulled that little factoid out of his a**.
“We have run the model over a simulated period of three million years, and taken into account measurements from ice cores and independent magnetic and seismic data”, says Petrunin. “Our model calculations are in good agreement with the measurements. Both the thickness of the ice sheet as well as the temperature at its base are depicted very accurately. “
So we trust computer models, now?
The weight of all the SUVs is compressing the earth’s crust.
Computer modeling is not science..............
Bet even he hurt his hemorrhoids when he pulled that little factoid out of his a**.............
Global mantle melting coming soon...
OMG, now AGW is heating up the Earth’s core.
It looks like the neutrinos coming from the sun have mutated into a new kind of nuclear particle. They’re heating up the earth’s core and suddenly act like microwaves.
LOL! That’s more credible than some of the “science” being espoused by the enviro-whacko crowd!
Now they have to figure out how to connect human beings to the heat of the Earth’s mantle.
I can hear them now, Overpopulation by man and his global distribution has catastrophically altered the plate weight and balance of the Earth!!!! We must immediately commence a accelerated program of euthanasia and cremation so as to re balance the Earth, volunteers are required and I suggest all environmentalists and liberals immediately report to the staging areas.
It is still Bush’s fault.
I thought the science was settled ...at Bush’s fault.
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