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ICE Satellite Maps Profound Polar Thinning

Posted by kdawson on from the skating-on-thin-ice dept.

xp65 writes "Researchers have used NASA's Ice, Cloud and Land Elevation Satellite to compose the most comprehensive picture of changing glaciers along the coast of the Greenland and Antarctic ice sheets. The new elevation maps show that all latitudes of the Greenland ice sheet are affected by dynamic thinning — the loss of ice due to accelerated ice flow to the ocean. The maps also show surprising, extensive thinning in Antarctica, affecting the ice sheet far inland. The study, led by Hamish Pritchard of the British Antarctic Survey in Cambridge, England, was published September 24 in Nature."

10 of 245 comments (clear)

  1. What is the net effect? by msevior · · Score: 4, Interesting

    I'm no climate change skeptic, but from just looking at the images it's not clear that the reduction in some places is not balanced by the increase in others. What is the net effect? Can these data be compared to model predictions?

    1. Re:What is the net effect? by khayman80 · · Score: 5, Informative

      One of the catastrophic outcomes of climate change are large sea level rises due to ice melt in the polar regions. Presumably there are models that predict how this could occur with global warming. So the question is, do these data agree with these models?

      The last article I read in Science compared model prediction of sea level rise, and found that observations showed the sea levels rising even faster than the models predicted. Perhaps this was just short-term weather, though: more recent measurements may indicate agreement with the models.

    2. Re:What is the net effect? by khayman80 · · Score: 4, Informative

      It's a better idea to get your science from scientists rather than politicians. The CO2 emissions by living organisms are part of a closed cycle, and those isotopes don't match the composition of the atmospheric CO2 that's currently ~26% higher than it's been in the last 650,000 years. Other sources such as volcanoes emit 100x less than humans do. Also, water vapor isn't relevant because it has a short lifetime in the atmosphere and isn't well-mixed to the top of the atmosphere. I've discussed all these issues at length.

    3. Re:What is the net effect? by EsbenMoseHansen · · Score: 5, Informative

      They have never been able to accurately predict what the weather will be tomorrow. It is arrogant for Al Gore (who incidentally also invented the Internet) to claim he knows what the effect will be decades from now. The largest cause of CO2 emissions is natural activity. The most abundant greenhouse gas is water vapor. http://en.wikipedia.org/wiki/Greenhouse_gas#Greenhouse_effects_in_Earth.27s_atmosphere

      3 myths in one go? Not bad. First link on google for climate myths gives 3 rebuttals: Chaotic systems are not predictable, CO2 isn't the most important greenhouse gas and finally CO2 isn't the most important greenhouse gas

      --
      Religion is regarded by the common people as true, by the wise as false, and by rulers as useful.
  2. Do they know if this is unusual? by n2rjt · · Score: 5, Interesting

    I see on the maps that some areas are thinning, near the coasts, and other areas are thickening.
    I wonder if that is the usual pattern, or if they are seeing something unusual.
    The article didn't mention that, as far as I could tell.

    1. Re:Do they know if this is unusual? by Beryllium+Sphere(tm) · · Score: 4, Insightful

      Qualitatively, what you'd expect from climate change is more precipitation (because there's more evaporation) and therefore thickening at high elevations where the snow stays cold, while lower warmer regions flow faster or even melt.

    2. Re:Do they know if this is unusual? by BrokenHalo · · Score: 4, Insightful

      and I'm really annoyed that health care is currently distracting the Senate from an issue that affects the future of the entire human race.

      Well, this doesn't help, but I can see why health care is the focus of attention: it is one thing the government can do something about. Climate change is a serious problem, but it is now too big to fix, since no-one has the will to adopt a policy amounting to more than "business as usual" and "let's have another toke on that big ole' oil-pipe".

      A lot of political mileage is being made of proposed emissions trading schemes, but it's too late for that. They are just accounting exercises - like pushing food around on the plate to make it look like you're eating less.

      I'm sorry if that sounds defeatist, but I'd be happy to hear an alternative. People will not change until they're forced to.

    3. Re:Do they know if this is unusual? by khayman80 · · Score: 4, Informative

      Assuming that large scale warming is already well under way (And that's a big assumption given the major cooling trend we have been in for the last 10 years.)

      I've discussed this claim before. Short version: there hasn't been a cooling trend over the last ten years, major or minor.

      It is likely, in fact nearly guaranteed that not only can't we do anything about it now, we probably NEVER were able to do anything about it.

      The climate varies naturally on long timescales but Meehl 2004 shows the current warming can't be accounted for by natural forcings. Greenhouse gas emissions are the only way we can explain the temperatures over the last ~40 years.

  3. Don't matter... by The+Master+Control+P · · Score: 4, Insightful

    Those who demand "proof" of climate change before we do anything to fight it will find some way to ignore this. They'll keep pretending there's "no evidence" and that it's a "librul conspiracy" until it becomes undeniable (I'm betting til the dams surrounding a port city fail) because they don't believe in doing anything proactive.

    Then when the engineers say it's too late to do anything except build a 300 foot tall dam around every coastline in the world, it'll be their fault for not fixing it.

    1. Re:Don't matter... by MartinSchou · · Score: 4, Insightful

      Well, with what is usually being proposed, like reducing carbon emissions by driving more fuel efficient cars, no leaving lights on everywhere, how is that POSSIBLY a bad thing?

      If we're talking about some of the more harebrained ideas like having hundred of thousands of ships sucking up cold water from the the ocean and spraying it as high into the atmosphere as possible, yes I agree - that could easily do serious long term damage that we don't realise.

      But conserving energy cannot do that, as we are simply choosing to reduce the energy input into a system that had previously had a moderately stable equilibrium before we started burning all those fossil fuels.