At its peak this winter, Arctic Ocean ice covered the smallest area since satellites started measuring it in 1979, researchers report.
Arctic sea ice probably reached its maximum extent for the year on March 7, at 5.65 million square miles, according to the University of Colorado-Boulderās National Snow and Ice Data Center.
That figure was 463,000 square miles (about the size of South Africa) less than the 1979-2000 average of 6.12 million square miles, and was about the same as in the winter of 2006, the center reported.
At its end-of-summer minimum in September, Arctic sea ice extent was the third-lowest since 1979.
Sea ice extent is the primary measure for assessing the condition of the ice cover, according to the National Oceanic and Atmospheric Administration.
The NOAA website has a time-lapse video showing how sea ice fluctuates and moves during winter.
āIām not surprised by the new data because weāve seen a downward trend in winter sea ice extent for some time now,ā National Snow and Ice Data Center scientist Walt Meier told Science Daily.
The seven lowest measurements of end-of-winter sea ice have been recorded in the last seven years, he told Science Daily.