Early October peak was lowest extent since 2008
This year’s El Niño may have been a factor limiting Antarctic sea ice, which peaked on October 6 at the lowest extent since 2008, according to an update from the National Snow and Ice Data Center.
The seasonal maximum extent rached about 7.27 million square miles, falling roughly in the middle of the record of Antarctic maximum extents compiled during the satellite record — in contrast to the past three years, which all set records.According to the NSIDC’s climate experts, Antarctic sea ice grew erratically this year, reaching higher than average levels early in 2015, then falling during the Southern Hemisphere winter in July and August. The sea ice cover recovered partially in September, but this year’s maximum extent is 513,00 square miles below the record maximum extent, which was set in 2014.
El Niño causes higher sea level pressure, warmer air temperature and warmer sea surface temperature in the Amundsen, Bellingshausen and Weddell seas in west Antarctica that affect the sea ice distribution.
“After three record high extent years, this year marks a return toward normalcy for Antarctic sea ice,” said Walt Meier, a sea ice scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “There may be more high years in the future because of the large year-to-year variation in Antarctic extent, but such extremes are not near as substantial as in the Arctic, where the declining trend towards a new normal is continuing.”
This year’s maximum extent occurred fairly late: the mean date of the Antarctic maximum is Sept. 23 for 1981-2010.