The extent and variability of South-East Atlantic upwelling

Abstract

The coastal upwelling regime of the South-East Atlantic Ocean has been investigated by means of satellite-derived weekly maps of sea surface temperature for the period 1982–1985. This preliminary investigation shows that this wind-induced upwelling system is restricted to the area between the Angolan Front and the Agulhas Bank. Within this area, eight distinct upwelling cells are identified. Frequency of occurrence, total zonal seaward penetration and prevalent wind-stress index during upwelling are highest for the central upwelling cell, that at Lüderitz, and decrease equator- and polewards. Average surface temperatures in the cells were inversely related to the other above-mentioned parameters, average temperatures being coldest in the Lüderitz cell and increasing in the other cells in both south- and northward directions.