ICE Satellite Maps Profound Polar Thinning

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."

Comments

Re:What is the net effect?

[khayman80]

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.

Re:Do they know if this is unusual?

[khayman80]

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.

Re:What is the net effect?

[khayman80]

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.

Re:What is the net effect?

[EsbenMoseHansen]

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