Warming in Antarctica is less than in the Arctic But along the Antarctic

Warming in antarctica is less than in the arctic but

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Warming in Antarctica is less than in the Arctic. But along the Antarctic Peninsula, a peninsula of land that juts out from Antarctica towards South America, the rate of warming is much higher than on the Antarctic mainland. Along this peninsula there have been many ice shelf collapses and disintegrations . Ice shelves are part of the ice sheets that extend over the sea while still attached to the continental ice. These ice shelves hold back from the sea the grounded continental ice to which they are attached. Ice shelves occur in many places around the continental margins of Antarctica. When the ice shelves deteriorate and break up, the continental ice sheets to which they are attached surge toward the sea. In 2002 AD for example, the Larsen B Ice Shelf, a 8000 square mile ice shelf (larger than Rhode Island), collapsed into icebergs. The Larsen B Ice Shelf was 11,000 years old. Ice shelves melt from the top because of warmer air temperatures, but also from the bottom as a result of warmer ocean temperatures. Sea ice has been reduced by 0.4 0 – 1.8 0 of latitude over the past century.
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Antarctica’s Inland Ice Sheets Antarctica’s inland ice sheets are melting very quickly. Between 1992 and 2011, 1,350 billion tons of ice disappeared into the oceans. That rate is now increasing, fueling global rises in sea level.
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Northern Canada Ward Hunt Ice Shelf, on Ellesmere island in Nunavut Territory, in northern Canada, broke up between 2000 and 2003. The shelf had been stable for 4500 years . It was the largest ice shelf in the Arctic. It reached what is called a systems threshold and rapidly broke up.
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Greenland Ice Sheet Greenland Ice Sheet covers 82% of the entire continent of Greenland. It is at least 110,000 years old. The Ice Sheet is three times the size of Texas. The ice sheet is melting at a rate of 239 km 3 (57 mi 2 ) per year. If the Greenland Ice Sheet completely melted, sea level would rise 23.6 feet (7.2 meters). This rise in sea level would completely inundate most of the world’s coastal cities. Climate models suggest that warming in Greenland this century will exceed 3 0 C (5.4 0 F). Summer of 2012 (July) – 97% of Greenland’s Ice sheet at the surface was melting. This melting was occurring faster than any scientists thought possible.
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Normal Ocean Process Near Greenland Ocean water becomes very dense and starts to sink (cold and dense). This drags warm surface water up from the tropics, helping create warmer conditions in Northern Europe than otherwise would be the case. Changing Ocean Process Near Greenland Ocean waters are becoming warmer now, plus more fresh water is running into the Northern Atlantic from the melting ice sheet in Greenland. Increased discharge of freshwater in the Arctic results in the Northern Oceans freshening, lowering salinity. Sea water in the Northern Atlantic is becoming much less dense than previously, and sinking of the water could stop any day now.
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