Sea ice covered 5.64 million square miles of the Arctic Ocean at the ice’s peak extent this year in early March. That’s almost 400,000 square miles less than the median coverage level at other March peaks between 1981 and 2010, according to the National Snow & Ice Data Center at the University of Colorado Boulder. The reduction is equivalent to an area larger than Egypt.
This year’s maximum extent of Arctic ice was the fifth lowest since satellite records began in 1979. And since that record-keeping started, the average ice extent for the entire month of March has shrunk by an average of 15,000 square miles a year, representing a loss of 880,000 square miles — an area bigger than Greenland.
Arctic winter ice typically covers the greatest expanse of ocean in March, after which it begins a slow melt over the spring and summer months, shrinking to its smallest area, or minimum extent, in September.
