Transfer of pollutants in two Southern hemispheric oceanic systems. Proceedings of a workshop held at Plettenberg Bay, South Africa

Abstract

Available information on the sources and principal routes by which pollutants enter the sea around southern Africa is summarized. The importance of different physical, chemical and biological processes is discussed in relation to the transfer of pollutants into and between the Agulhas and the Benguela oceanic systems around southern Africa. The two systems serve as examples of an oceanic current and an upwelling system. Extrapolations are drawn, as far as possible, to the rest of the southern hemisphere and similar conditions elsewhere. The major pollutant types discussed include petroleum hydrocarbons, toxic elements, organic wastes, halogenated hydrocarbons, radioactive materials and heat. Processes involved in the transfer of pollutants to the sea, transfer across watermass boundaries and interface transport processes are discussed. The relative importance of different processes is assessed, gaps in knowledge are identified and recommendations are made for future research.