Slowing ocean current caused by melting Antarctic ice could have drastic climate impact, study says
GuardianMay 25, 2023
According to a new study, changes to circulation in parts of the Southern Ocean are taking place faster than expected, with potentially negative implications for Earth's broader climate and biodiversity.
The new study, which was published [on May 25] in the journal Nature Climate Change, found evidence that at least one area of the Southern Ocean — that regulates the climate and regulates the transfer of heat, carbon, oxygen, and nutrients between ocean layers — is changing faster than previously expected.
This slowing circulation is extremely worrying because it shows that there are consequences for this melting Antarctic ice, beyond just rising sea levels. This new study is a warning sign of what potential future changes could occur to crucial ocean cycles as ice melt continues. The global community needs to step up and immediately reduce greenhouse gas emissions before it's too late.
While the study found a slowing of circulation in the Australian Antarctic Basin, observations don't yet show the same rapid trends occurring in other spots around Antarctica. This finding is concerning, but there's still time to turn things around in line with global attempts to reduce CO2.
Despite these latest findings, Antarctic ice melt may yet reverse thanks to natural processes. The melting of the West Antarctic ice sheet may not be permanent. Bedrock cores show that ice in Antarctica grew back several thousand years ago after a severe thaw. This evidence suggests that rising landmasses may contribute to slowing glacial melt and sea level rise. There's reason for optimism based on cycles from deep Earth history.
There is a 50% chance that the Thwaites Eastern Ice Shelf will collapse by Oct. 2026, according to the Metaculus prediction community.