March 16 () –
In February 2023, the sea ice around Antarctica reached the lowest extent ever observed. since the inception of satellite recording in 1979.
But despite several recent years of low extents, the long-term trend for sea ice in south polar waters is essentially flat; are the decreases in sea ice at the other pole, in the Arctic, the ones that are pushing down the global sea ice trend.
Sea ice around Antarctica reached its lowest point on February 21, 2023, with 1.79 million square kilometers. That’s 130,000 square kilometers below the previous record low reached on February 25, 2022, a difference that is equivalent to an area the size of New York state. It is the second time that scientists have observed that the ice shrinks below 2 million square kilometers, reports NASA.
The map above shows the ice extent on the day of its record low. To determine the extent, scientists project satellite observations of sea ice onto a grid and then add up the total area of each cell that is at least 15 percent covered in ice. The yellow outline shows the median extent of sea ice in February from 1981 to 2010. A median is the middle value; that is, half of the extensions were larger than the yellow line and half were smaller.
Amid the variability from year to year, Antarctic sea ice trends prior to 2016 were generally heading slightly upwards in all months. Several years since have hit new all-time lows, including 2017, 2022, and now 2023.
“There is some discussion about the Antarctic sea ice regime change since 2016 towards a generally smaller extent, and that perhaps this could be a response to global warming – that is, the warming signal is beginning to be seen in Antarctic sea ice. above the variability from year to year,” said Walt Meier, a sea ice scientist at the National Snow and Ice Data Center (NSIDC). “But it’s hard to say at this point if this is a real change and response to warming, or just a temporary variation of several years.”
