Melting Antarctic ice will slow the world’s strongest ocean current – and the global consequences are profound
From The Conversation (3/3/25)…
Melting Antarctic ice will slow the world’s strongest ocean current – and the global consequences are profound
Flowing clockwise around Antarctica, the Antarctic Circumpolar Current is the strongest ocean current on the planet. It’s five times stronger than the Gulf Stream and more than 100 times stronger than the Amazon River.
It forms part of the global ocean “conveyor belt” connecting the Pacific, Atlantic, and Indian oceans. The system regulates Earth’s climate and pumps water, heat and nutrients around the globe.
But fresh, cool water from melting Antarctic ice is diluting the salty water of the ocean, potentially disrupting the vital ocean current.
Our new research suggests the Antarctic Circumpolar Current will be 20% slower by 2050 as the world warms, with far-reaching consequences for life on Earth.
The Antarctic Circumpolar Current keeps Antarctica isolated from the rest of the global ocean, and connects the Atlantic, Pacific and Indian oceans. Sohail, T., et al (2025), Environmental Research Letters., CC BY
Why should we care?
The Antarctic Circumpolar Current is like a moat around the icy continent.
The current helps to keep warm water at bay, protecting vulnerable ice sheets. It also acts as a barrier to invasive species such as southern bull kelp and any animals hitching a ride on these rafts, spreading them out as they drift towards the continent. It also plays a big part in regulating Earth’s climate.
Unlike better known ocean currents – such as the Gulf Stream along the United States East Coast, the Kuroshio Current near Japan, and the Agulhas Current off the coast of South Africa – the Antarctic Circumpolar Current is not as well understood. This is partly due to its remote location, which makes obtaining direct measurements especially difficult.
Understanding the influence of climate change
Ocean currents respond to changes in temperature, salt levels, wind patterns and sea-ice extent…..
