A new Australian-led study warns that in a high-emissions future, the Antarctic Circumpolar Current—Earth’s strongest ocean current—could slow down by 20% by 2050, further accelerating Antarctic ice melt and sea level rise.
The Antarctic Circumpolar Current is a massive clockwise-flowing current, more than four times stronger than the Gulf Stream, linking the Atlantic, Pacific, and Indian Oceans. It plays a crucial role in regulating global climate, influencing heat and carbon dioxide uptake in the ocean while keeping warmer waters from reaching Antarctica.
Using Gadi, Australia’s fastest supercomputer and climate simulator, researchers modelled the impact of rising temperatures, melting ice, and changing wind patterns on the current. Their findings, published in Environmental Research Letters, revealed a direct link between Antarctic meltwater and the slowing of the circumpolar current, signalling a significant shift in Southern Ocean dynamics.
Assoc. Prof. Bishakhdatta Gayen of the University of Melbourne described the results as “quite alarming.” He explained that as Antarctic ice melts, it releases cold, fresh water into the ocean, which sinks and spreads toward the equator, altering ocean density—a key circulation driver—leading to the slowdown.
“The ocean is an extremely complex and finely balanced system. If this current ‘engine’ breaks down, we could see severe consequences, including more climate variability, extreme weather in certain regions, and accelerated global warming as the ocean’s ability to absorb carbon weakens,” Gayen warned.
These findings come just days after another study predicted a weakening of vital Atlantic Ocean currents, further underscoring the urgent need for global action to reduce emissions and protect the planet’s climate-regulating systems. Read More
News Credit: The Guardian
Illustration: Dr Taimoor Sohail