Some features in two Cape bays as deduced from satellite ocean-colour imagery

Abstract

Imagery from the Nimbus-7 and Landsat-3 satellites shows pronounced mesoscale features in two bays on the west coast of South Africa. Sea surface truth measurements indicated that the high subsurface upwelling radiance at 520 nm in St Helena Bay was probably the result of the presence offish oil on the sea surface, a presence which could be associated with extensive pollution of the sea by fish processing factories in the area. The equally high radiance observed in False Bay was apparently not associated with pollution, and the crescent-shaped plume evident from the imagery was ascribed to natural oceanographic processes. It is concluded that satellite ocean-colour imagery has an application in monitoring the extent of organic pollution provided that sea truth measurements are made concurrently. © 1983 Taylor & Francis Group, LLC.