Satellite data reveal how the new record low Arctic sea ice extent, from Sept. 16, 2012, compares to the average minimum extent over the past 30 years(in yellow) . Sea ice extent maps are derived from data captured by the Scanning Multichannel Microwave Radiometer aboard NASA's Nimbus-7 satellite and the Special Sensor Microwave Imager on multiple satellites from the Defense Meteorological Satellite Program.The new record minimum measures almost 300,000 square miles less than the previous lowest extent in the satellite record, set in mid-September 2007, of 1.61 million square miles (4.17 million square kilometers).
