The Antarctic Circumpolar Current (ACC) is accelerating due to climate change, which could have significant impacts on local climate and marine ecosystems. The ACC is the only ocean current that circles the entire globe, transporting up to 150 million cubic meters of water per second. It plays a crucial role in the Earth’s climate by forming a natural boundary between the warmer south and the cold Antarctic waters. Until now, the ACC was thought to be largely immune to climate change. However, a study by scientists at the University of California San Diego shows that the ACC is not as stable as previously believed and is being accelerated by climate change.
The study, published in the journal Nature Climate Change, analyzed the most extensive dataset on the ACC to date, combining satellite measurements since 1993 with data from buoys observing the current since 2005. The researchers found a significant acceleration of the ring current, particularly in the Pacific and eastern Indian Ocean regions. The acceleration is caused by the warming of the Southern Ocean, which has disproportionately affected the upper water layers and heated the area north of the ring current. This warming has created temperature differences between the regions around the current, leading to the observed acceleration.
The acceleration of the ACC could have significant impacts on regional climate and marine ecosystems, as it facilitates the exchange of factors such as heat and carbon between different ocean basins. The study’s authors predict that the acceleration will continue and may even intensify as long as the waters north of the ring current continue to warm. The findings highlight the need for continued monitoring of the ACC and its impacts on the Earth’s climate and marine ecosystems.
