New Video Reports on ‘Unstoppable’ Antarctic Glacial Melting

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It’s not often that a scientific research paper generates the kind of media attention and scientific community buzz that resulted from a recent study on the apparent inevitability of substantial Antarctic glacial melting.


The early May research headed by lead author Eric Rignot of NASA called attention to melting now under way in Antarctica that CBS News anchor Scott Pelley reported “cannot be stopped.”

“Scientists say the situation is almost certainly unstoppable,” NBC News Anchor Brian Mitchell reported.

Rignot cautioned that the research indicates “we’ve passed the point of no return … It’s just a matter of time before these glaciers disappear to the sea.” While he indicated that the full melt, at the current pace, might not occur for two centuries, he pointed too to evidence suggesting the likelihood of an accelerating pace.

“There’s probably nothing that can be done to stop this,” Rignot said.

“This is really happening,” lead NASA lead polar ice researcher Tom Wagner said. “This weak underbelly of Antarctica is in fact starting to float out into the sea, and there’s not a lot to hold it back.”

A “This is Not Cool” video on the report by independent videographer Peter Sinclair is the first to be posted under the new Yale Climate Connections name, formerly The Yale Forum on Climate Change & The Media. The official transition to that newly named site is to get underway over the next few weeks, initially with a largely cosmetic rebranding, then to be followed by a substantial overhaul and a more multi-media emphasis aimed at better reaching the general public.

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15 Responses to New Video Reports on ‘Unstoppable’ Antarctic Glacial Melting

  1. Peter Capen says:

    Those who persist in their steadfast denial that the sea is rising and the pace is accelerating are simply unwilling to face the reality the infrastructure, commercial, and residential properties along the shore are doomed to be “stranded” investments, which everyone will eventually be hit with the overwhelming costs of, especially, through not exclusively, future generations. While a number of communities and municipalities are already grappling effects of rapidly rising sea levels, states and those charged with making policy at the federal level are doing little to nothing to face up to the enormity of the challenge that now faces us and the need to galvanize this nation once and for all into meaningful action. To deny the reality of a serious problem, as Republicans have recently done in cutting off funding for the military’s climate research, is nothing short of criminal behavior. Had American leaders and the public been so shortsighted when World War II was knocking at our doorstep and failed to call the nation into cooperative action, we might well have lost that war and would all have suffered the consequences as a result. A reliance on the “hidden hand of the market” without government intervention insures the effects of increased global warming will only get dramatically worse.

  2. Bob Bingham says:

    My bench mark for sea level is one metre because at that level eleven of the worlds fifteen largest cities are flooded. The economic blow of losing a big lump of Florida or the Gulf coast would be huge. At the same time farming and food production will be having real difficulties and so the scenario is not good. http://www.climateoutcome.kiwi.nz/climate-threats.html

    • Jon Parker says:

      I think it is about half that. At 18 inches, there will be increased coastal flooding with high tides and winds. Even inland Florida will see high water because of porous limestone. When coastal insurance and flood insurance start to reflect the real, actuarial cost, properties will become unsalable. Once that starts, it will snowball. It started last year in Texas where some home owners saw their insurance costs rise from $5,000 per year to $25,000. Rates were rolled back, but it will happen.

  3. Bob Koss says:

    Antarctica is the southern most point of the Pacific Ring of Fire. The Hudson mountains appear to be at the head of the Pine Island Glacier. They have some volcanoes, although none are known to be active.

    No link has been provided for the paper, and no mention in the video of having considered the possibility of new sub-surface volcanic activity or fumaroles contributing to warming of the land or sea beneath those glaciers. It would be interesting to know if they even considered the possibility.

    Can’t say I’m very surprised the newscaster laid it off on global warming. I don’t remember any of the scientists in the video mentioning it at all. Maybe they are starting to realize the public becomes increasingly skeptical when they tout what they can’t prove. Or maybe those parts were left on the cutting room floor.

    • Martin Lack says:

      Although Antarctica is home to the southern-most active volcano on the planet (Mt Erebus), I am not sure why you are raising the subject of volcanoes. They are not cited as a concern in connection with the melting of the WAIS (or any other part of Antarctica) because there is no reason to believe that volcanic activity levels are increasing beneath the continent, whereas there is a great deal of evidence to suggest that even the very modest warming of the oceans we have caused so far is has now resulted in destabilisation of the WAIS.

      • Bob Koss says:

        That no reference is made at all is the reason I said I was interested. Being on the Ring of Fire it should naturally be a consideration, with some reason given if the possibility is rejected.

        I doubt they are aware of all active sub-surface vents. From time to time you still read about them discovering such things which have been belching for many years previous to discovery in other areas of the world. I’m not inclined to simply assume there are none unless they make an explicit statement saying they know none exists due to someone recently making a comprehensive search of the area and have found it to be not possible.

        It would only take them a paragraph to make such a statement. Has it been done or not? If it has, what is their confidence in the search results? If it hasn’t, my confidence in their reasoning is lessened.

        • Chuck Hughes says:

          I don’t think your “confidence in their reasoning” matters to the Climate. The facts are in and the science is settled. Any volcanic activity has already been considered and it’s not a factor in the melting of the WAIS. It wasn’t a factor the last time the ice sheets melted either. Scientists KNOW what is causing the ice sheets to melt. Read and study the science. If you have any beach front property you might want to sell it now.

          Here you go:

          http://www.skepticalscience.com/argument.php

  4. Paul Quigg says:

    To me the video distinctly shows sea water undermining very deep glaciers which are on land. How this water could undermine the glacier for any significant distance without breaking off is beyond my structural engineering knowledge. Everyone knows floating ice is 90% below the waters surface. My glacier climbing experience warms of the peril of extended time spent below a glacier which flows over a ridge and cracks off creating extremely unstable ice “beehives”. There is no cantilever of ice which extends far out over the air, they crack off at cantilevers far less then the total thickness of the ice in long spikes. When we can’t avoid traveling below a “beehive” we rush across at night when it is coldest.
    I believe this hypothesis is impossible, and I am deeply skeptical of the findings.

    • Nullius in Verba says:

      The findings are not new, the implications in the popular press are more dubious. It’s standard physics that glaciers are always either retreating or expanding, depending on whether precipitation upstream is less than or greater than the rate of loss at the margins. (Loss is primarily by calving, rather than melting.) The theory is that if surface area at the edge increases as the ice retreats (or decreases as it expands) this growth or loss is ‘unstable’.

      However, antarctic ice has been retreating since the end of the last ice age, and the process is very slow, on human timescales. (It’s fast by the standards of geological timescales, but changes occurring over thousands of years are beyond any reasonable human planning window.) As I understand it, the melt rate corresponds to around 0.5-1.0 mm/yr sea level rise, which is still well within the bounds of the rate at which the land can rise to match it, so there doesn’t appear to be a problem here. Over centuries to millennia, cities can be moved.

      Mechanically, ice is a brittle solid down to 50 m when the pressure makes it a plastic fluid. Glaciers flowing into water rest on the bottom until the water depth exceeds 9 times the thickness of the ice, and then start to float. As they float the bed friction drops to zero and they start to spread out, thinning in the process, and when the thickness drops to around 50 m it stops flowing and becomes brittle, breaking off in chunks.

      Floating ice is unaffected by the water depth, and poses no resistance to flow upstream. The depth of ice at the grounding line (i.e. where it last touches the sea bed) is 10/9 times the sea depth at that point, and flows at a rate related to the slope of the upper ice surface. If the gradient is steep enough, the flow across the line will be fast, and the glacier will lose more than it gains from precipitation upstream, and retreat. It will also thin faster. The balance of all these effects is complicated, and the flow is uneven and difficult to predict, but there isn’t much room in it for temperature to have much effect. Once floating, there isn’t any resistance to the motion so whether it melts or thins/fractures makes little difference. While on solid land, temperature changes at the surface of the glacier take a long time to propagate through the ice. It’s a poor conductor of heat. The primary variable would seem to be precipitation – the more snow falls, the thicker the ice in the middle, the thicker and faster the flow at the margins, the further out the grounding line will be.

      Certainly, there is some possibility of meltwater penetrating the glacier (the brittle upper layer at least) and carrying heat below, to lubricate the base. But this is highly speculative and uncertain. There doesn’t appear to be any clear theoretical prediction, and the data is over too short a period to tell signal from noise. We don’t know.

      But there’s a distinct possibility that this is a natural change triggered by the weather over the past several centuries, reducing precipitation below the threshold where it can keep up with the loss at the edges. There’s no reason given here to think it hasn’t been going on for several thousand years. You need to ask the right questions.

      • Nullius in Verba says:

        Oops! Thatg should be “until the water depth exceeds 9/10 times the thickness of the ice”

        • Paul Quigg says:

          A little past 2 minutes in the video the illustration showed flowing water undermining the glacier for a distance of more then 50km. It is impossible for a 50km cantilever of ice to not fail. Your explanation stated that the glacier slides on the sea bed until 90 percent of the glacier height was below sea level is consistent with my understanding. Sea level has risen one foot, plus or minus, in the last 100 years so how is this water creeping under a glacier for vast distances with so little sea level rise? And, what does this have to do with climate change?
          I have seen deep gorges in the Athabaska River region which were cut by subterranean Ice Age melting but the ice was certainly resting on the land above.
          I have never heard of a plastic liquid below 50m, what is its viscosity?

          • Nullius in Verba says:

            “so how is this water creeping under a glacier for vast distances with so little sea level rise?”

            If the ice layer is thin enough, it floats. The water supports it through buoyancy.

            “And, what does this have to do with climate change?”

            Nothing.

            “I have never heard of a plastic liquid below 50m, what is its viscosity?”

            About 2*10^13 Pascal-seconds. Although it varies with temperature and with stress (i.e. glacier ice is a non-Newtonian fluid).

          • Paul Quigg says:

            I now realize the ice in question is below sea level and the “ground” I was talking about is actually ocean bottom. I looked at some topo of Antartica and saw that much of the shore ice is sitting on the ocean floor. Thanks for your help.

  5. Bob Koss says:

    Wow! I must be more influential than I thought.

    I inquired above about being part of the Ring of Fire as a possible reason for the melting around Pine Island and Thwaites glaciers and someone comes out with a study confirming geothermal effects underneath Thwaites glacier are at least part of the reason.

    http://www.ibtimes.co.uk/west-antarctic-thwaites-glacier-melting-below-through-geothermal-heat-1451930

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