Earth’s Most Powerful Ocean Current Sensitive to Global Warming

Nature, 27 March 2024

Sediment records from the past five million years reveal that the massive Antarctic Circumpolar Current (ACC) speeds up and slows down depending on Earth’s temperature, with previous warm periods bringing faster flow and increased Antarctic ice loss. During warm periods, these currents generate eddies that redirect warm water underneath floating ice shelves. Most relevantly, this study applies these findings to today’s Antarctic Circumpolar Current. Researchers have already observed a speedup over recent decades, most likely driven by fossil fuel emissions, and caution that continued temperature rise will bring worsening impacts intensified by a faster Antarctic Circumpolar Current: greater ice loss, increased global sea-level rise, and reduced Southern Ocean ability to absorb carbon from the atmosphere.

Full paper: https://www.nature.com/articles/s41586-024-07143-3
Plain-language briefing: https://news.climate.columbia.edu/2024/03/27/key-ocean-current-contains-a-warning-on-climate/