Thursday, July 26, 2012


ICE SHEET IS MELTING FAST - I wasn't hugely surprised to see the news from Nasa about unprecedented melting of most of the Greenland ice sheet surface. Much of Greenland has been experiencing record warmth since May, and on the 29th of that month the weather station in the extreme south reached a positively balmy 24.8C, which set a new record May temperature for the country; this is significant because records from several weather stations extend back to the late 19th century. 
The unusually warm conditions prevailed for much of June and into July, with the Danish Meteorological Institute website showing Greenland temperature anomalies about 2-4C higher than the 1961-90 baseline average during these last three months. For every 1C rise in temperature, the resulting effect is to increase the amount of melt by around a third, so we might expect double the climatological "normal" amount of meltwater being produced by the ice sheet during June and July this year.

The Nasa satellite picture of melt covering most of the ice sheet surface on 12 July is dramatic, and several key Greenland scientists have confirmed it is unprecedented in the satellite record going back to the late 1970s. However, Nasa also cites evidence from ice cores at the summit of the ice sheet that suggest similar wholesale melting events occur once every 150 years on average, and the last one was in 1889. If this is this case, the recent melt may be due to natural climate variability, so do we have anything to worry about? 
Even without sustained global warming, the Greenland ice sheet is living on borrowed time. If all the ice sheet melts, sea levels will rise by more than seven meters. Although it will take several thousand years for the ice to melt in its entirety according to current estimates, it is quite possible that the ice sheet could add up to several tens of centimetres to the global sea level by 2100. This would make many coastal communities more vulnerable to flooding and storm surges.

Nasa Satellite observations earlier this month (corroborated by several independent satellite methods and research groups) have revealed a dramatic and unprecedented level of ice melt in Greenland. Scientists say an estimated 97 % of Greenland's ice sheet surface thawed at some point in mid-July. This is really bad news, the human-enhanced global warming have led to more warm air and more warmth clearly means more melting. We must stop releasing greenhouse gases.

The environmental community rightly recognizes global warming as one of the gravest threats to the planet.  The expected consequences include coastal flooding, increases in extreme weather, spreading disease, and mass extinctions.  Yet by focusing entirely on carbon dioxide emissions, major environmental organizations have failed to account for published data showing that other gases are the main culprits behind the global warming we see today. ... Animal agriculture produces more than 100 million tons of methane a year. And this source is on the rise.  About 85% of this methane is produced in the digestive processes of livestock, and while a single cow releases a relatively small amount of methane, the collective effect on the environment of the hundreds of millions of livestock animals worldwide is enormous. ... Simply by going vegetarian we can eliminate one of the major sources of emissions of methane, the greenhouse gas responsible for almost half of the global warming impacting the planet today.

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