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The facts

There is clear scientific evidence of the reduction of ice in the Arctic due to global warming.

Average ice extent for September 2011 was 4.61 million km2 (1.78 million square miles), 2.43 million km2 (938,000 square miles) below the 1979 to 2000 average (see ssss1). This was 310,000 square kilometers (120,000 square miles) above the average for September 2007, the lowest monthly extent in the satellite record. Ice extent was below the 1979 to 2000 average everywhere except in the East Greenland Sea, where conditions were near average.

While recent studies have shown that in wintertime Antarctic sea ice has a weak upward trend, and substantial variability both within a year and from year to year, the differences between Arctic and Antarctic sea ice trends are not unexpected. Climate models consistently project that the Arctic will warm more quickly than the Antarctic, largely due to the strong climate feedbacks in the Arctic. Warming is amplified by the loss of ice cover in the Arctic Ocean in areas that had been ice-covered for decades, and by the warming of Arctic lands as snow cover is lost earlier and returns later than in recent decades.