ACC

Antarctic Circumpolar Current

This is an ocean current that flows clockwise from west to east around Antarctica. Another name for the ACC is the West Wind Drift.

The ACC is the major circulation component of the Southern Ocean. It is approximately 125 Sverdrups in size  - one of the largest ocean currents in the world.

The current is able to completely circle the planet because of the lack of any landmass connecting with Antarctica. This current keeps warm ocean waters away from Antarctica, enabling that continent to maintain its huge ice sheet.

Around 35 million years ago, when South America and Antarctica separated, the ACC may have first formed and contributed to isolating Antarctica and allowing it to form it's vast ice sheet.

Definition based on (revised from) IPCC AR4.