Polar sea ice the size of India vanishes in record heat
Sea ice off Antarctica and in the Arctic is at record lows for this time of year after declining by twice the size of Alaska in a sign of rising global temperatures, climate scientists say.
Against a trend of global warming and a steady retreat of ice at earth's northern tip, ice floating on the Southern Ocean off Antarctica has tended to expand in recent years.
But now it is shrinking at both ends of the planet, a development alarming scientists and to which a build-up of man-made greenhouse gases, an El Nino weather event that this year unlocked heat from the Pacific Ocean and freak natural swings may all be contributing.
"There are some really crazy things going on," said Mark Serreze, director of the U.S. National Snow and Ice Data Center (NSIDC) in Boulder, Colorado, saying temperatures in parts of the Arctic were 20 degrees Celsius (36°F) above normal some days in November.
Combined, the extent of polar sea ice on Dec. 4 was about 3.84 million square kilometers (1.48 million square miles) below the 1981-2010 average, according to NSIDC satellite measurements. That is roughly the size of India, or two Alaskas.