Tereza Pultarova writes:

Antarctica may be in serious trouble. Satellite images show that the amount of sea ice floating around the pristine polar continent remains far below long-term averages despite the south polar region moving into its peak winter period.

Researchers at the British Antarctic Survey (BAS) observed with trepidation in late 2022 and early 2023 as satellite images revealed that sea ice attached to the coast of Antarctica had been disappearing month after month at a pace never seen before. And they continued to observe in near horror as this sea ice failed to sufficiently replenish after the colder months arrived. As of mid-June 2023, sea ice extent in Antarctica was about 0.9 million square miles (2.28 million square kilometers) below the average from 1981 to 2010 for that part of the year, according to the U.K. weather authority Met Office, and about 0.4 million square miles (1.15 million square km) below the previous June record low from 2019.

This development is a worrying deviation from a previous trend that saw Antarctica hold quite steady against progressing climate change, which has long been decimating its northern counterpart, the Arctic. Scientists now worry that the frozen southernmost continent, which plays a crucial role in stabilizing the global climate, may be reaching its tipping point, a point of no return beyond which the polar ecosystem as we know it won’t be able to survive.

“In the Arctic, we have seen a steady decline [of sea ice] over time,” Peter Fretwell, a remote-sensing scientist at the BAS, told Space.com. “Antarctica, up until 2016, was steady, even getting more sea ice, which we couldn’t understand. But since 2016, it’s gone down, and it’s going down even more at the moment. Something has happened, and it’s gone down suddenly very much.”

The amount of floating ice surrounding the polar continent dropped to an all-time low in late February this year, shrinking to 691,000 square miles (1.79 million square km). That’s 50,000 square miles (130,000 square km) below the previous record low of February 2022, according to NASA, which followed a previous record low from 2021.

The problem is, as Fretwell said, that “what happens to Antarctica doesn’t just stay in Antarctica.” The warming polar seas affect weather patterns all over the world and accelerate the melting of Antarctic glaciers that, in turn, will lead to faster sea level rise around the globe. [Continue reading…]