Arctic sea ice is low, with the Bering Sea’s ice extent “the lowest recorded since at least 1979,” according to the National Snow and Ice Data Center (NSIDC). This reflects a larger overall trend: in April, Arctic sea ice covered an area 378,400 square miles below the 1981 to 2010 average. According to Alaska-based meteorologist Rick Thoman, Bering Sea ice extent “is five percent of normal” for the middle of May, and “there is almost nothing left except for near shore ice in protected areas.” The worrisome part of all this? There are still four months to go in the Arctic’s melt season.
NSIDC provided information on Arctic sea ice extent in April of this year, and said 2016 and 2018 essentially tied “for lowest April sea ice extent on record.” Barents Sea and Bering Sea ice extent was below average, as it was during the 2017 to 2018 winter. According to Earther, the Bering Sea has been something of a ground zero for crazy ice, with sea ice disappearing when it was supposed to be growing in February, rebounding slightly in March, and then plummeting in April.
Bering Sea ice extent is 5% of normal for mid-May and there is almost nothing left except for near shore ice in protected areas. Chukchi Sea ice extent also at record low, with open water now north of 71N. #akwx #Arctic @Climatologist49 @ZLabe @lisashefguy @amy_holman pic.twitter.com/Ur7UmoptgL
— Rick Thoman (@AlaskaWx) May 17, 2018
Warm oceans have played a role in the dive of Bering Sea ice levels; University of Alaska Fairbanks climate researcher Brian Brettschneider told Earther that “Bering Sea SSTs [sea surface temperatures] have been at record or near record levels for months now. This represents a strong positive feedback. Warm waters are hard to freeze, which then allows for more solar absorption.”
And Bering Sea ice typically protects Chukchi Sea ice. When Bering Sea ice disappeared in February, open water seeped into the Chukchi Sea — an event that has probably only happened in one other winter on record.