The vast polar ice cap, which regulates the Earth's temperature and
has been a permanent fixture in our understanding of how the world
works, has this year retreated further and faster than anyone expected.
The previous record, set in 2007, was officially broken on 27 August
when satellite images averaged over five days showed the ice then
extended 4.11 million sq km, a reduction of nearly 50% compared to just
40 years ago.
But since 27 August, the ice just kept
melting – at nearly 40,000 sq km a day until a few days ago. Satellite
pictures this weekend showed the cap covering only 3.49m sq km. This
year, 11.7m sq km of ice melted, 22% more than the long-term average of
9.18m sq km. The record minimum extent is now likely to be formally
called on Monday by the US National Snow and Ice Data Centre (NSIDC) in
Colorado.
The record hasn't just been broken, it's been smashed to smithereens, adding weight to predictions that the Arctic may be ice-free in summer months within 20 years,
say British, Italian and American-based scientists on board the Arctic
Sunrise. They are shocked at the speed and extent of the ice loss.
http://www.guardian.co.uk/environment/2012/sep/14/decline-sea-ice-arctic
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