Ice Melt

According to the Arctic Monitoring and Assessment Program guidelines, the Arctic region currently encompasses thirty-three million square kilometers, or more than one-sixth of the world's landmass.  Larger even than Africa or Asia, the Arctic, located north of the Arctic Circle, is warming at more than twice the rate of the rest of the world.  NASA satellite images indicate that perennial sea ice cover has decreased at a rate of 9% per decade since the 1970s, a trend that, unless reversed, could bring ice-free Arctic summers within the next hundred years.  The 2007 ice cover lows were about a quarter lower than previous record lows set in 2005 and the trend in ice cover loss has accelerated from between -2.2 and -3.0% per decade from 1979-1996 to -10.1 and -10.7% per decade from 1997-2007.  In 1987, 57% of the Arctic Basin ice pack was more than 5 years old and 14% was more than 9 years old. By 2007, there was no ice pack older than 9 years old in the Arctic Basin and only 7% of the ice was older than five years.  From 2006 to 2007, NASA satellite images showed a 16% year-over-year cloud cover decrease, a change that if perpetuated could have significant and rapid negative consequences on the already melting Arctic ice pack.  With anywhere between eight and sixteen million square kilometers of pack ice present at a given time, significant melting levels will mean fundamental changes in the Arctic region. To get an idea of the scope of the problem, it is instructive to examine some documented changes. For instance, on August 13, 2005 a chunk of ice the size of eleven thousand football fields broke free from the Ayles Shelf off the North Coast of Ellesmere Island, 500 miles south of the North Pole.  The calving was substantial enough to register as a small earthquake 160 miles away at a Canadian military base.  Additionally, the Greenland Ice Sheet's annual loss of mass has risen from 22 to 36 cubic miles between 1999 and 2005.