Antarctic Circumpolar Current (ACC)

node · earth · Southern Ocean — circumpolar

The largest current on Earth and the only one that circles the globe without meeting a coastline. Driven by the strongest sustained westerlies on the planet and unblocked by land, it runs eastward around Antarctica and connects the Atlantic, Pacific and Indian basins into one system — which is what makes a global overturning circuit possible at all. Continuous measurements in Drake Passage from 2007 to 2011 gave a mean transport of 173.3 Sv, the sum of a mean barotropic component of 45.6 ± 8.9 Sv and a baroclinic component of 127.7 Sv relative to zero at the seafloor. That total is about 30 per cent larger than the 134 Sv figure that had served as the benchmark for climate models for decades.