Scientists continue to document a sea surface cooling in the vast waters above Antarctica.
As recently as a few thousand years ago the Sub-Antarctic (South Georgia) region was 5 to 10°C warmer than it is today (Xia et al., 2020).
Image Source: Xia et al., 2020
About 1,000 years ago (the Medieval Warm Period) Antarctica was still “substantially warmer than present” and the Southern Ocean waters were sufficiently ice-free that elephant seals could breed in the Ross Sea, or near the coast of south-central Antarctica’s Victoria Land.
Today this region is so much colder and the sea ice so thick that elephant seals must travel 2,400 kilometers north of where they used to breed 1,000 years ago just to find sea ice-free waters (Koch et al., 2019; Hall et al., 2006).
Image Source: Koch et al., 2019
Image Source: Hall et al., 2006
And now some new studies (Atkinson et al., 2022, Toolsee and Lamont, 2022) document a cooling/non-warming trend in the southwest Atlantic and/or Sub-Antarctic region has commenced in the last few decades. The cooling follows a long-term warming trend that lasted from the 1920s to 1990s.