Antarctic sea ice extent increased gradually over much of the satellite record (1979 to present), reaching successive record highs in 2012-14. Yet, 2016 saw the beginning of the most pronounced fall in sea ice cover ever observed. Over the three years that followed, the precipitous drop in Antarctic sea ice was equivalent to 30 years of sea ice loss in the Arctic.

These fluctuations led the Intergovernmental Panel on Climate Change (IPCC) to conclude in its 2019 special report on the ocean and cryosphere that Antarctic sea ice extent “overall has had no statistically significant trend” due to “contrasting regional signals and large interannual variability”.

A perspective paper, published in Nature Geo science, draws on recent research to examine what the recent dramatic loss in Antarctic sea ice cover reveals about the processes that control sea ice in the region.