The Antarctic Circumpolar Current, the strongest ocean current on Earth, is at risk of slowing down by 20% by 2050, according to new research. This powerful current, five times stronger than the Gulf Stream, plays a vital role in regulating global climate and ecosystems. It connects the Pacific, Atlantic, and Indian oceans, circulating heat, nutrients, and water globally.

However, fresh, cool water from melting Antarctic ice is diluting the salty ocean water, potentially disrupting this crucial current. Despite expectations that warming water would speed up the current, recent observations suggest stability in its strength. But new ocean models predict that the influx of meltwater will weaken the current due to changes in ocean density and circulation.

A weaker Antarctic Circumpolar Current could have significant consequences, including reduced biodiversity, a decline in fishery productivity, and the spread of invasive species. Furthermore, it could accelerate the melting of Antarctica’s ice sheets, contributing to rising sea levels and intensifying climate change. Reducing greenhouse gas emissions and conducting long-term studies of the Southern Ocean could help mitigate these risks.