Geography Reference
In-Depth Information
The Antarctic Convergence (sometimes termed the 'Antarctic polar front' or the 'polar
frontal zone'), where the cold body of water that is the Southern Ocean meets the warmer
waters of the Indian, Pacific, and Atlantic Oceans, provides another definition of the
Antarctic. Rather than a latitudinal delineation, we have here an oceanographic/climatic
frontier that acts as a zone of transition emphasizing movement and connection. The con-
vergence itself varies from year to year, depending on sea temperature and climatic trends.
So these are flows that make, remake, and unmake a zone of some 30-50 kilometres in
width, encircling the polar continent, and stretching north of South Georgia and Bouvet
Island. It roughly coincides with the mean February isotherm (10°C) and lies around
58°S, considerably north of the Antarctic Circle. Air and sea surface temperatures change
markedly once one crosses the Antarctic Convergence. In resource management terms, the
Antarctic Convergence is significant because of the wealth of marine life, especially plank-
ton and shrimp-like krill - the food of choice of birds, fish, and whales - that is found there.
