Some 2.5 million sq kms of perennial ice have been lost - about one and a half times the area of Alaska - a 50 per cent decrease between February 2007 and February 2008, Meier said.
The oldest "tough as nails" perennial ice has decreased by about 75 per cent this year, losing 1.5 million sq kms, or about twice the area of Texas, he said.
18 Mar 2008
Thickest, oldest sea ice melting: NASA
A bad sign:
