Antarctic Convergence

Antarctic waters predominantly sink beneath the warmer subantarctic waters, while associated zones of mixing and upwelling create a zone very high in marine productivity, especially for Antarctic krill.

The Arctic has no similar boundary because of the large bodies of land contiguous with the northern polar region.

The Antarctic Convergence was first crossed by Anthony de la Roché in 1675[1] and Edmond Halley in 1700,[2] and first described by the British Discovery Investigations and the German Meteor Expedition in 1925–1927.

Although the northern boundary varies, for the purposes of the Convention on the Conservation of Antarctic Marine Living Resources 1980, it is defined as "50°S, 0°; 50°S, 30°E; 45°S, 30°E; 45°S, 80°E; 55°S, 80°E; 55°S, 150°E; 60°S, 150°E; 60°S, 50°W; 50°S, 50°W; 50°S, 0°.

The precise location at any given place and time is made evident by the sudden drop in seawater temperature from north to south of, on average, 2.8 °C (5.0 °F) from 5.6 °C (42.1 °F) to below 2 °C (36 °F).