Key Ocean Current Contains a Warning on Climate – State of the Planet

The Antarctic Circumpolar Current, the mightiest and fastest current on the planet, plays a crucial role in regulating global climate. A recent study using sediment cores from remote waters reveals that the current has moved in tandem with Earth’s temperature over the last 5.3 million years. During past cold times, the current slowed down, while in warm times, it gained speed, leading to major losses of Antarctica’s ice. The study suggests that the current’s current speedup will continue as human-induced warming progresses, hastening the wasting of Antarctica’s ice and potentially affecting sea levels and the ocean’s ability to absorb carbon from the atmosphere. These findings were published in the journal Nature. The study involved an international research team drilling sediment cores in the Earth’s most remote waters to extract a 5.3 million-year record of the Antarctic Circumpolar Current. The current started flowing in its modern form about 12 to 14 million years ago, driven by continuous westerly winds around Antarctica. The increasing strength of winds over the Southern Ocean has accelerated the current, transporting warm waters towards Antarctica’s ice shelves and contributing to their wasting. The study indicates that future global warming will further enhance the ACC flow, with potentially negative consequences.