Antarctic sea ice is melting faster than expected

Terms of melting could further reduce Antarctic sea ice extent.

Antarctic sea ice extent reached a record high in late February since satellite measurements began 45 years ago, the leading US observatory announced on Monday.

Antarctic sea ice melts in summer and recovers in winter. In mid-February, the American National Snow and Ice Data Center (NSIDC) announced that even before the end of the summer, it had melted more than in 2022, already beating its record.

But the melting continued, and this time the sea ice probably reached its minimum extent for the year, at 1.79 million square kilometers , on February 21, 2023, the observatory said.

He said, however, that this figure was preliminary and that continued melting conditions could push the ice extent further down. A formal announcement is expected in early March.

The melting of sea ice does not have an immediate impact on sea levels, as it is formed by freezing of salt water already present in the ocean.

“Lower sea ice extent means that ocean waves will hit the shores of the ice sheet, further reducing the ice barriers around Antarctica.

— Ted Scambos, NSIDC Contributing Researcher

However, the ice sheet – the thick freshwater glacier that covers Antarctica – is particularly monitored by scientists because it contains enough water to cause catastrophic sea level rise if it melts.

Furthermore, the white sea ice reflects the sun's rays more than the darker ocean, and its loss thus accentuates global warming.

In February 2022, Antarctic sea ice fell below 2 million square kilometers for the first time. The years 2017 and 2018 had also reached a very low range (third and fourth lowest).

“The trend Falling sea ice could be a signal that global warming has finally affected the ice floating around Antarctica, but it will take several more years to be sure.

—Ted Scambos, NSIDC Contributing Researcher

The effect of global warming on Arctic sea ice, where temperatures are rising far more faster than on the rest of the earth, is it already well proven.