![ThwaitesTongue-600x423[1]](https://wattsupwiththat.files.wordpress.com/2014/06/thwaitestongue-600x4231.png?quality=75)
Remember the wailing from Suzanne Goldenberg over the “collapse” of the Thwaites glacier blaming man-made CO2 effects and the smackdown given to the claim on WUWT?
Well, never mind. From the University of Texas at Austin and the “you can stop your wailing now” department, comes this really, really, inconvenient truth.
Researchers find major West Antarctic glacier melting from geothermal sources
AUSTIN, Texas — Thwaites Glacier, the large, rapidly changing outlet of the West Antarctic Ice Sheet, is not only being eroded by the ocean, it’s being melted from below by geothermal heat, researchers at the Institute for Geophysics at The University of Texas at Austin (UTIG) report in the current edition of the Proceedings of the National Academy of Sciences.
The findings significantly change the understanding of conditions beneath the West Antarctic Ice Sheet where accurate information has previously been unobtainable.
The Thwaites Glacier has been the focus of considerable attention in recent weeks as other groups of researchers found the glacier is on the way to collapse, but more data and computer modeling are needed to determine when the collapse will begin in earnest and at what rate the sea level will increase as it proceeds. The new observations by UTIG will greatly inform these ice sheet modeling efforts.
Using radar techniques to map how water flows under ice sheets, UTIG researchers were able to estimate ice melting rates and thus identify significant sources of geothermal heat under Thwaites Glacier. They found these sources are distributed over a wider area and are much hotter than previously assumed.
The geothermal heat contributed significantly to melting of the underside of the glacier, and it might be a key factor in allowing the ice sheet to slide, affecting the ice sheet’s stability and its contribution to future sea level rise.
The cause of the variable distribution of heat beneath the glacier is thought to be the movement of magma and associated volcanic activity arising from the rifting of the Earth’s crust beneath the West Antarctic Ice Sheet.
Knowledge of the heat distribution beneath Thwaites Glacier is crucial information that enables ice sheet modelers to more accurately predict the response of the glacier to the presence of a warming ocean.
Until now, scientists had been unable to measure the strength or location of heat flow under the glacier. Current ice sheet models have assumed that heat flow under the glacier is uniform like a pancake griddle with even heat distribution across the bottom of the ice.
The findings of lead author Dusty Schroeder and his colleagues show that the glacier sits on something more like a multi-burner stovetop with burners putting out heat at different levels at different locations.
“It’s the most complex thermal environment you might imagine,” said co-author Don Blankenship, a senior research scientist at UTIG and Schroeder’s Ph.D. adviser. “And then you plop the most critical dynamically unstable ice sheet on planet Earth in the middle of this thing, and then you try to model it. It’s virtually impossible.”
That’s why, he said, getting a handle on the distribution of geothermal heat flow under the ice sheet has been considered essential for understanding it.
Gathering knowledge about Thwaites Glacier is crucial to understanding what might happen to the West Antarctic Ice Sheet. An outlet glacier the size of Florida in the Amundsen Sea Embayment, it is up to 4,000 meters thick and is considered a key question mark in making projections of global sea level rise.
The glacier is retreating in the face of the warming ocean and is thought to be unstable because its interior lies more than two kilometers below sea level while, at the coast, the bottom of the glacier is quite shallow.
Because its interior connects to the vast portion of the West Antarctic Ice Sheet that lies deeply below sea level, the glacier is considered a gateway to the majority of West Antarctica’s potential sea level contribution.
The collapse of the Thwaites Glacier would cause an increase of global sea level of between 1 and 2 meters, with the potential for more than twice that from the entire West Antarctic Ice Sheet.
The UTIG researchers had previously used ice-penetrating airborne radar sounding data to image two vast interacting subglacial water systems under Thwaites Glacier. The results from this earlier work on water systems (also published in the Proceedings of the National Academy of Sciences) formed the foundation for the new work, which used the distribution of water beneath the glacier to determine the levels and locations of heat flow.
In each case, Schroeder, who received his Ph.D. in May, used techniques he had developed to pull information out of data collected by the radar developed at UTIG.
According to his findings, the minimum average geothermal heat flow beneath Thwaites Glacier is about 100 milliwatts per square meter, with hotspots over 200 milliwatts per square meter. For comparison, the average heat flow of the Earth’s continents is less than 65 milliwatts per square meter.
The presence of water and heat present researchers with significant challenges.
“The combination of variable subglacial geothermal heat flow and the interacting subglacial water system could threaten the stability of Thwaites Glacier in ways that we never before imagined,” Schroeder said.
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From the department of recycled news …
The article I read about this paper (on Fox News I think) made it sound like things were extra bad because the geothermal heat was combining with the effects of CAGW to make the ice shelves collapse super fast…
No, it’s because the Global Warming is soooo bad that it’s melting the glacier – from underneath! And it’s heating the rocks, too! Aaaaagh!
The more we know, the more we realise the little we really know about our planet
One of my father’s favourite sayings was “a little bit of knowledge is a dangerous thing”. He used it often to rebut my youthful, bolshie ravings in the late 60’s and early seventies. I now know that, after his time as a field commander in the SW pacific campaigns, he finished WW2 as a brigade/divisional intelligence officer and such an expression must have had particular resonance and “dangerous” was not just that of being wrong in an academic sense.
Doesn’t it speak so eloquently to “Climate Science” and in particular aspects of it such as the West Antarctic Ice sheet behaviour.
Even if Thwaites were the size of Florida (it objectively is not) the entire Amundson Embayment is much larger, and IF all its ice was ever lost (so that part of west Antarctica would be bare naked) it would amount to 1.2 meters SLR. All the evidence (ice flow rates, snow accumulation) say that will never happen. Whether or not subglacial volcanos are contributing. Just another PhD thesis.
More Warmunist alarmism.
That must be the missing heat that went directly into the asthenosphere and finally comes back up.
It’s all the CO2 destabilising the tectonic plates….or something….
The use of the gas top burner together with an average of 0.1 to 0.2 watts/sqm confuses the issue somewhat given the vast area under research. We might have a number of concentrated hot spots that would have a very different effect to an average increase in heat over the entire area.
At last, we have the missing link between man-made CO2 and magma dynamics. The atmosphere is heated by CO2. It heats the glacier. The superheated melt water under intense pressure from the overlying 4km of ice heats the magma to its melting point. One more reason to reduce CO2 output.
Remember the first sentence of the press release being quoted? Maybe the selective highlighting is needed here:
Well never mind. Ignore the undesirable part in bold then.
Leonard Pitts blames the GOP.http://www.dailycamera.com/columnists/ci_25914184/pitts-while-our-planet-melts-gop-pleads-ignorance
We think we know so much about the earth, yet we don’t have the historical data from the last thousand years to compare notes with. Just like every other controversial subject in this country, there is normally corrupt lobbying power behind it for one reason or another. We need more transparency in everything that is digitally printed.
“The glacier is retreating in the face of the warming ocean and is thought to be unstable because its interior lies more than two kilometers below sea level while, at the coast, the bottom of the glacier is quite shallow.”
Now correct me if Im wrong.
This glacier is not floating ice.
This glacier is not land borne ice either because its below sea level.
Now someone correct me here, but -if- this glacial is largely below sea level, and ice having a larger volume compared with water, will the complete melting of this glacier not tend to make the sea level fall?
At least the below sea level part will have an effect on how much contribution it makes to sea level change. That is assuming that it actually melts within a time of a few hundred years, not more than 2,000 years the IPCC gives to the Greenland ice cap.
And of course, if it is melting because of seismic activity, I can see why we simply have to ban all coal fires in the world! Not!
Cheers
Roger
http://thedemiseofchristchurch.com (My blog on Agenda21 and my earthquaked city)
I love this line “Current ice sheet models have assumed that heat flow under the glacier is uniform like a pancake griddle with even heat distribution across the bottom of the ice” My question is who was the idiot, yes I use idiot a lot, but show one place on earth where the geothermal heat is evenly distributed. The answer is no place on earth does that occur. The sad reality is those that can do those who cannot teach. I just did not realize how bad those who cannot are!
Damn that man-made C02 –now it’s causing geothermal heat! Is there no limit to the atrocities man has committed on mother gaia?
Odd.
from http://earth.esa.int/workshops/ers97/papers/lucchitta/
But the area of Florida is only 170,304 square km’s.
Even if you include the entire area that the Twaites drains it is ,er, uhm, considerably smaller than Florida.
“According to his findings, the minimum average geothermal heat flow beneath Thwaites Glacier is about 100 milliwatts per square meter, with hotspots over 200 milliwatts per square meter. For comparison, the average heat flow of the Earth’s continents is less than 65 milliwatts per square meter.”
These figures aren’t huge. 100 isn’t a lot greater than average. 0.1 W/m2 is tiny compared with average sunlight, even in Antarctica. It’s enough to melt about 1 cm thickness of ice per year.
As I read the paper, they aren’t saying that geothermal is melting the main mass of the ice, but that it has “the potential to modulate ice sheet behavior and stability by providing a large, variable supply of meltwater to the subglacial water system, lubricating and accelerating the overlying ice”.
With things like geothermal, the natural question is, if it is having a big effect now, why not before?
Most glaciers are melting from below through geothermal heat, either volcanic or simple bedrock temperatures.
That is why the oldest ice on Greenland is only 128,000 years old yet the island has been glaciated for 2.7 million years to 8.0 million years.
That is why the oldest ice on Antarctica is only 800,000 years old yet the location where this old ice formed has been glaciated for over 42 million years.
The issue is, a headline is needed to promote the warming agenda. Thermodynamics tells a different story. It is a sad story, this global warming science.
Nick,
Perhaps the better question is to ask if the effect that is claimed to be so big is actually so big?
At least we finally know where all that missing heat in the ocean is hiding…
cartoon!
http://182.160.156.173/~itsnotcl/0038.html
Odd. Another “interesting” factoid from this 1992-1994 study of the Thwaites and Pine Island Glaciers that don’t make sense when compared to last month’s hysteria about the two melting/toe lines/retreat/grounding lines propaganda (er, publicity) prior to the EPA’s new rules to destroy the US economy.
http://earth.esa.int/workshops/ers97/papers/lucchitta/
So, in 1992-1994, there is NO MENTION AT ALL of any “at sea” grounding line .. only that both glaciers leave land (traveling at a slower rate over that land than they do when floating over sea water) and then extend into the sea past a “grounding line” and are “floating” while at sea. All of which makes sense: A glacier on land is going to be expected to move slower than a glacier floating on sea water, and a glacier on sea water will move away from the land far enough that – eventually – it will start to break off pieces (calve icebergs) and melt away.
But – in May – all we heard from the “experts’ was that the WAIS was “jammed” or stuck against an at-sea grounding line that was backing up the glacier and preventing motion. That, if the glacier tip continued to melt (from below where it had been stopped at the former/present grounding line) then the end of the glacier would move over the water (from the grounding line) and would lead to catastrophic melting of the whole WAIS.
WTF? This 1992-1994 study shows NONE of that could be occurring since the whole glacier is leaving from a well-known continental land mass edge out into open water. Has the Pine Mountain glacier and Thwaites glaciers EXTENDED further from the continental land boundary so far between 1992 and 2014 that the tip is NOW so far out that it NOW hits an underwater shallow spot that it could not have reached in 1992?
This is definitely a useful contribution because it explains why the rate of movement of the Thwaites Glacier is faster than what would be expected if the base of the glacier were locked to the bedrock and the movement is the result only of shear within the glacier.
This study, combined with others, explains [the] rate of movement from purely natural causes and not from accelerated warming caused by man.. .
However, the article contains an unscientific alarmist statement:
“The collapse of the Thwaites Glacier would cause an increase of global sea level of between 1 and 2 meters, with the potential for more than twice that from the entire West Antarctic Ice Sheet.”
This statement is obviously calculated to inspire fear. It is unscientific because there is no time period, no indication if the rate of rise of sea level is faster or slower than now or in the past.
This is important, because sea level rises during interglacials and the longer the time between the onset of the interglacial, the more the sea level rises. During the last interglacial (Eemian), maximum sea level was at least 3 meters high than now. In the very long interglacial 400,000 years ago (MIS 11) sea level was about 20 meters higher than now.
If the astronomer André Berger and others are correct, that the present interglacial (Holocene) will last 50,000 years, mankind may witness sea level 20 meters higher than at present. But this would happen with or without the intervention by mankind. It would happen if all humans had continued with Stone Age technology.
Unfortunately, the level of scientific literacy is so low, even in the developed countries of the world, that the public has little defense against this sort of slanted reporting. The journalists are no more literate in science than their readers.
In my opinion, the thing that will eventually damp down climate alarmism is another 10 to 20 years of no warming or the onset of mild cooling.
Some assumptions need to be made to do the math Mark, and in fact simply by choosing how to construct the model you make assumptions. The whole purpose of this fellow’s grant was to improve our poor understanding of glacial dynamics, i.e. collect the data necessary to improve those models and lift the poor assumption of even heat distribution. There is no “sad reality,” just a bad cliche.
To quote Newton, “If I have seen further it is by standing on the shoulders of giants”