For five years, a scientific expedition tried reaching Pine Island Glacier ice shelf in a remote, wind-ridden corner of Antarctica. The obstacles to get to the ice shelf were extreme, but the science goal was simple: to measure how fast the sea was melting the 37-mile long ice tongue from underneath by drilling through the ice shelf. The international team, led by NASA's emeritus glaciologist Robert Bindschadler and funded by the National Science Foundation and NASA, had to abort their mission in 2007....Those measurements taken on and below the Pine Island Glacier ice shelf have yielded their first scientific results, determining the rate at which warm sea water is eating away the ice from underneath the floating portion of the glacier.
In a paper published in the journal Science on Sept. 13, the team describes how at one of their study sites, halfway down the ice shelf, the melt rate was as high as 2.36 inches (6 centimeters) per day.
From Thinkprogress; "An international team of researchers found that Antarctica’s Pine Island Glacier, the single largest Antarctic contributor to sea-level rise, could add as much as one centimeter to ocean levels within the next 20 years. The glacier “has started a phase of self-sustained retreat and will irreversibly continue its decline,” Gael Durand, a glaciologist with France’s Grenoble Alps University, told Australian Broadcasting Corporation.
“At the Pine Island Glacier we have seen that not only is more ice flowing from the glacier into the ocean, but it’s also flowing faster across the grounding line — the boundary between the grounded ice and the floating ice,” Dr. G. Hilmar Gudmundsson, a researcher on the project, told Planet Earth Magazine. The glaciologists found that that glacier’s grounding line, which has already receded up to 10 kilometers this century, is “probably engaged in an unstable 40-kilometer retreat.”
According to the latest research, Antarctic ice melt has caused global sea level to rise by about 0.02 centimeters a year for the last 20 years. Last year’s Intergovernmental Panel on Climate Change report stated that there was “high confidence that ice shelves around the Antarctic peninsula continue a long-term trend of retreat and partial collapse that began decades ago.”
CSMonitor reports that; "Antarctic glacier melt is a major cause of rising sea levels. With the help of a robotic underwater vehicle, scientists have now determined why one big glacier is disappearing. The rate at which the ice shelf is melting has increased significantly, because more warm water is circulating in the cavity beneath it…The inner cavity didn’t exist at all before, so this is the most likely explanation for why a subtle change in temperature can have a huge effect."
Science.time.com reports; "We already know that Arctic ice is melting faster than expected, and that sea level rise will likely bust the IPCC predictions. Now, thanks to a new paper published yesterday in Nature Geoscience, we have a better idea of why. Researchers from the British Antarctic Survey (BAS) and Columbia University’s Lamont-Doherty Earth Observatory examined the Pine Island Glacier in West Antarctica—one of the frozen continent’s largest glaciers—and found that it was melting more than 50% faster than it had been just 15 years ago, when an earlier group of scientists visited it. The glacier is now losing 80 cu. km of ice a year, up from 50 cu. km in 1994."
Read more: A New Study Shows Why an Antarctic Glacier Is Melting, and Underscores the Uncertainty in Climate Models | TIME.com
In the TravelChannel TV show below, Zay Harding goes on a tour of the Antarctic, and talks with a scientist who had gone down there for ten years. The scientist tells Zay that when he first got there, the station where they were at was right next to a glacier, which ended right there at the research station. One section of the glacier broke off about once a week ten years ago, and that was a big deal, so they all went outside to see it. Since then, the glacier has retreated about 1/2 mile, and the calving has accelerated to 7 times a DAY, rather than once a week. Now the calving happens to often, they do not even watch it anymore, nor go outside for this very frequent happening.
In another section of the show, biologists show how one species of Antarctic penguin has had their population reduced from 15,000 to 3,000, due to the climate warming in the Antarctic so much that their eggs drown in sitting rain water, rather than sitting on top of ice.
The Pliocene sedimentary sequence in the drillcore consisted of sixteen distinct layers, alternating between diatom-rich silty clay and diatom-poor clay layers with silt laminations. Diatom-rich sediments point to multiple extended periods of increased biological productivity related to less sea ice and warmer spring and summer sea surface temperatures. This sequence is in good agreement with data from marine and land-based records from the Antarctic Peninsula margin, the Ross Sea and other areas.Reconstructions indicate that during the Pliocene there were prolonged (~200,000 years) warm intervals, when spring and summer sea surface temperatures were between 2 and 6 oC above modern levels, with a general background theme of warmer-than-present temperatures.
http://www.nbcnews.com/science/science-news/volcano-under-antarctic-ice-may-erupt-accelerate-melting-f2D11603371
A European satellite show melting of an antarctic ice sheet is accelerating, losing more than 35 cubic miles of ice annually, scientists say. The loss observed by the European Space Agency's CryoSat is considerably more than when the area was last surveyed, they said. The total is dominated by ice losses from three glaciers flowing into the Amundsen Sea, a release from the Paris headquarters of the ESA said Thursday.
Read more: http://www.upi.com/Science_News/2013/12/13/Satellite-confirms-accelerating-melting-of-antarctic-ice-sheets/UPI-96411386979787/#ixzz2uHKJ5z6oWhat is the take away from all of these studies and other research? Global warming is affecting even an area that is farthest away from all human activities, in the Southern Hemisphere. The melting of the Arctic ice caps and retreating glaciers are well established and easy to see in the Arctic, but now the same process has been documented as happening in the Antarctic region too.
End
Accelerating Antarctic Ice Sheet Melt, Antarctic Glaciers Receding; via @AGreenRoad
http://agreenroad.blogspot.com/2014/02/accelerating-antarctic-ice-sheet-melt.html
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