The Washington Post reports:

Sea ice levels around Antarctica just registered a record low — and by a wide margin — as winter comes to a close, according to the National Snow and Ice Data Center (NSIDC). This significant milestone adds worry that Antarctic sea ice may be entering a state of decline brought on by climate change.

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“There is some concern that this may be the beginning of a long-term trend of decline for Antarctic sea ice, since oceans are warming globally, and warm water mixing in the Southern Ocean polar layer could continue,” read the NSIDC announcement released Monday.

Sea ice around the polar regions grows and melts with the seasons. In Antarctica, sea ice typically hits its minimum coverage at the end of the Southern Hemisphere’s summer around February. It reaches its maximum extent at the end of winter in mid- to late September. This February, scientists reported Antarctic floating sea ice hit an all-time low at the end of the summer — and sea ice growth continued to remain slow through winter.

This year, Antarctica reached its annual maximum coverage on Sept. 10, about 13 days earlier than average. At that time, the annual ice coverage was at a record low of 6.55 million square miles — a whopping 398,000 square miles lower than the previous record low set in 1986.

“It is surprisingly low,” said Twila Moon, an ice scientist at NSIDC. “We have this extreme low minimum and there hasn’t been any ability to recover towards previous higher extents during the Antarctic fall and Antarctic winter. … We’re starting to see this year round influence.” [Continue reading…]