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  • Geothermal Heat Melting Antarctic Glacier

    Geothermal heat may be the big player when it comes to the melting western ice sheet in Antarctica.

    From the University of Texas:
    Major West Antarctic Glacier Melting from Geothermal Sources

    June 10, 2014
    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.
    This map shows the locations of geothermal flow underneath Thwaites Glacier in West Antarctica that were identified with airborne ice-penetrating radar. The dark magenta triangles show where geothermal flow exceeds 150 milliwatts per square meter, and the light magenta triangles show where flow exceeds 200 milliwatts per square meter. Letters C, D and E denote high melt areas: in the western-most tributary, C; adjacent to the Crary mountains, D; and in the upper portion of the central tributaries, E. Credit: University of Texas Institute Geophysics.

    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.

    For more information, contact: University Communications, Office of the President, 512 471 3151; Anton Caputo, Geology Foundation, Jackson School of Geosciences,

    Be kinder than necessary because everyone you meet is fighting some kind of battle.

  • #2
    Re: Geothermal Heat Melting Antarctic Glacier

    “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.


    I find it interesting that the author speaks as if this important information is 1) critical in nature; and 2) something that we are able to do something about.

    Climate changes, and we are not really able to do anything about underseas volcanoes. Still, I suppose it is a good thing that they are warning people that they think that beach front property is going to be further inland than it used to be...!

    Comment


    • #3
      Re: Geothermal Heat Melting Antarctic Glacier

      Originally posted by Forrest View Post
      “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.


      I find it interesting that the author speaks as if this important information is 1) critical in nature;
      given that the overwhelming majority of our population lives within 100 miles of the ocean, it might matter a great deal.

      and 2) something that we are able to do something about.

      Climate changes, and we are not really able to do anything about underseas volcanoes.
      creative thinking might reveal ways of offsetting the effects of one phenomenon by intervening in some other phenomenon.

      Comment


      • #4
        Re: Geothermal Heat Melting Antarctic Glacier

        Originally posted by jk View Post
        .....creative thinking might reveal ways of offsetting the effects of one phenomenon by intervening in some other phenomenon.
        getting back to your recent idea of settin off a big... uhhh... firework ... 'to effect change' - jk?
        ;)

        Comment


        • #5
          Re: Geothermal Heat Melting Antarctic Glacier

          This is important info for everyone who thinks that CO2 from AGW is the main cause of the ice sheets melting. I think we all know that carbon taxes are just a money grab, but they're harder to justify in light of information like this. Time and money would be better spent preparing rather than arguing about carbon. Just my uninformed $0.02...

          Be kinder than necessary because everyone you meet is fighting some kind of battle.

          Comment


          • #6
            Re: Geothermal Heat Melting Antarctic Glacier

            If the thing slides off (likely), how long does it take to raise sea level? Does it "fall" into the ocean and raise things like a tidal wave? Or, does it just melt over 10 years so we have time?

            Comment


            • #7
              Re: Geothermal Heat Melting Antarctic Glacier

              Originally Posted by Forrest

              “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.


              I find it interesting that the author speaks as if this important information is 1) critical in nature;


              Originally posted by jk View Post
              given that the overwhelming majority of our population lives within 100 miles of the ocean, it might matter a great deal.


              "Critical in nature" generally means that the effects are critical now...as in "the glaciers will all melt in the next few weeks, and we better get ready".


              I am tired of 'the sky is falling' reporting style. It will take years for that much glacier to melt, and the effect will be gradual, and hence able to be dealt with.

              I grant that it is a serious matter...I do not think it will cause anyone to prepare until the water noticeably rises. People will then start packing up, and moving inland. It's been happening for eons.


              Originally Posted by Forrest

              and 2) something that we are able to do something about.

              Originally posted by jk View Post
              Climate changes, and we are not really able to do anything about underseas volcanoes.
              On this we agree.


              Originally posted by jk View Post
              creative thinking might reveal ways of offsetting the effects of one phenomenon by intervening in some other phenomenon.
              Mastering climate variations is a bit beyond our current scientific and technical expertise. Still, assuming it were possible, how do you remove water from the ocean at the same speed it is melting by any phenomenon?

              Originally posted by jk View Post
              given that the overwhelming majority of our population lives within 100 miles of the ocean, it might matter a great deal.
              Climate changes affect everyone, not just those living along the coast.

              The water being realeased into the antarctic will irrevocably change the way the oceans are warm and cooled, affecting the entire world climate, while the fishing will be affected by a sudden release of fresh water into the sea, marine mammals breeding areas will be affected, and so forth. Our weather will continue to change erratically, and not just at the coast.

              Even so, the entire planet will have to cope with the changes and our inability to affect our new circumstances.

              The information is certainly valuable...the reporting technique is tiresome.

              Comment


              • #8
                Re: Geothermal Heat Melting Antarctic Glacier

                Originally posted by Forrest View Post
                ....
                The information is certainly valuable...the reporting technique is tiresome.
                +1
                but then... the 'shockumentary' is a means to sell eyeballs...

                oh and uhhhh... yeah... almost fergot the most critical:
                primarily more of the evidence to keep the .gov/edu research-industrial complex humming.

                and the(ir) gravy train flowing....
                Last edited by lektrode; 06-17-14, 11:49 AM.

                Comment


                • #9
                  Re: Geothermal Heat Melting Antarctic Glacier

                  Originally posted by shiny! View Post
                  This is important info for everyone who thinks that CO2 from AGW is the main cause of the ice sheets melting. I think we all know that carbon taxes are just a money grab, but they're harder to justify in light of information like this. Time and money would be better spent preparing rather than arguing about carbon. Just my uninformed $0.02...
                  does it make a difference if climate change is caused by human activity? should the fact noah didn't make the rain mean he shouldn't have bothered building an ark?

                  and i actually think carbon taxes is the best proposal on the table to make some difference. even if we just slow the changes, it gives society more time to adapt. carbon taxes can be revenue neutral- that's a separate choice. e.g. one could tax carbon and do away with social security taxes which are very regressive, and increase the earned income tax credit. also a carbon tax doesn't create a carbon MARKET [like cap and trade] to be manipulated and leeched off of.

                  Comment


                  • #10
                    Re: Geothermal Heat Melting Antarctic Glacier

                    Originally posted by jk View Post
                    does it make a difference if climate change is caused by human activity? should the fact noah didn't make the rain mean he shouldn't have bothered building an ark?
                    That's what I was trying to say. As always, you said it better than I could.

                    Many governments seem fixated on carbon as being the sole cause of global warming/climate change. If factors such as geothermal warming or sunspots actually play a major role, "solutions" that are totally focused on carbon reduction will fail to remedy problems such as coastal flooding. If, OTOH, people agree that regardless of CO2, ice sheets are going to slide off and melt, they can start preparing response policies rather than hoping that carbon reductions will solve everything.

                    and i actually think carbon taxes is the best proposal on the table to make some difference. even if we just slow the changes, it gives society more time to adapt. carbon taxes can be revenue neutral- that's a separate choice. e.g. one could tax carbon and do away with social security taxes which are very regressive, and increase the earned income tax credit. also a carbon tax doesn't create a carbon MARKET [like cap and trade] to be manipulated and leeched off of.
                    I agree with you that anything we can do to slow the process will give us more time to prepare, but I don't know how effective carbon taxes will be if CO2 is rising as an effect of warming, rather than being the cause of warming.

                    How much will carbon taxes reduce total global carbon output if wealthy countries implement them while poor countries that can't afford to, don't?

                    I'm not being argumentative, I genuinely want to know. There are so many contradictory claims, each one touted to be the truth and pushed with religious zeal by people with political biases and financial agendas. I don't know what to think. Regardless of the role that carbon plays in global warming I'm all in favor of reducing carbon pollution for the health benefits if nothing else.

                    Be kinder than necessary because everyone you meet is fighting some kind of battle.

                    Comment


                    • #11
                      Re: Geothermal Heat Melting Antarctic Glacier

                      Originally posted by shiny! View Post

                      Many governments seem fixated on carbon as being the sole cause of global warming/climate change. If factors such as geothermal warming or sunspots actually play a major role, "solutions" that are totally focused on carbon reduction will fail to remedy problems such as coastal flooding. If, OTOH, people agree that regardless of CO2, ice sheets are going to slide off and melt, they can start preparing response policies rather than hoping that carbon reductions will solve everything.



                      I agree with you that anything we can do to slow the process will give us more time to prepare, but I don't know how effective carbon taxes will be if CO2 is rising as an effect of warming, rather than being the cause of warming.

                      How much will carbon taxes reduce total global carbon output if wealthy countries implement them while poor countries that can't afford to, don't?

                      I'm not being argumentative, I genuinely want to know. There are so many contradictory claims, each one touted to be the truth and pushed with religious zeal by people with political biases and financial agendas. I don't know what to think. Regardless of the role that carbon plays in global warming I'm all in favor of reducing carbon pollution for the health benefits if nothing else.
                      whether carbon is the CAUSE or not, we know that reducing or limiting carbon dioxide and methane will slow the warming process. the point of intervention need not be the point of cause. as to whether there's any value in, say, the u.s. passing a carbon tax, i think the jury's out. there are two arguments to made for it, i think: one is that if the u.s., as a rich country that can afford it better, doesn't do it, then certainly neither will anyone else; the other is that if we impose a carbon tax, we have the right to impose tariffs on imports from countries that don't impose a carbon tax. that is ok under world trade agreements. this would have the effect of both offering a little protection to domestic companies and exerting pressure on global exporters to follow our lead.

                      Comment


                      • #12
                        Re: Geothermal Heat Melting Antarctic Glacier

                        Originally posted by jk View Post
                        whether carbon is the CAUSE or not, we know that reducing or limiting carbon dioxide and methane will slow the warming process. the point of intervention need not be the point of cause. as to whether there's any value in, say, the u.s. passing a carbon tax, i think the jury's out. there are two arguments to made for it, i think: one is that if the u.s., as a rich country that can afford it better, doesn't do it, then certainly neither will anyone else; the other is that if we impose a carbon tax, we have the right to impose tariffs on imports from countries that don't impose a carbon tax. that is ok under world trade agreements. this would have the effect of both offering a little protection to domestic companies and exerting pressure on global exporters to follow our lead.
                        You make some good points. Thanks, jk.

                        But my cynical self thinks that if we did institute a carbon tax on ourselves, we would never have the stones to implement trade tariffs on countries that don't. The globalist corporate oligarchy would cry about free markets. Since they own the politicians they would kill any tariff legislation. Our largest creditor, China, would threaten to cut off the credit spigot. Trade wars or even the threat of trade wars would end any silliness about tariffs. Third world trading partners would shift their exports to less demanding countries. So instead of giving us a more even playing field, a carbon tax would handicap us while giving the advantage to overseas manufacturers.

                        But I am very ignorant and a lousy chess player so please tell me where I'm wrong.

                        Be kinder than necessary because everyone you meet is fighting some kind of battle.

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                        • #13
                          Re: Geothermal Heat Melting Antarctic Glacier

                          If the carbon taxes did not go into Wall Street's and War Street's pockets, I would agree. Those taxes collected, however, will just be another damn tax.

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                          • #14
                            Re: Geothermal Heat Melting Antarctic Glacier

                            Originally posted by aaron View Post
                            If the carbon taxes did not go into Wall Street's and War Street's pockets, I would agree. Those taxes collected, however, will just be another damn tax.
                            exactly! - its the same with the fantasy that a VAT would/could/might allow or cause (about the time pigs are flying)
                            an offset of the income tax and would likely be sold as a (just another) 'remedy for inequality'

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