The Delagoa Bight eddy

Abstract

The results of two recent research cruises show that the cyclonic Delagoa Bight eddy observed on satellite imagery fills most of the continental shelf and terrace landward of the Mozambique Current at all depths, but is particularly dominant below 100 m depth. It consists of well-mixed Equatorial Surface and Sub-Tropical Water underlain by an upwelled dome of Antarctic Intermediate Water. A detailed analysis of all available historic hydrographic data from the last 25 years demonstrates the prevalent nature of the eddy. Sediment patterns on the shelf support the concept of a quasi-permanent topographically trapped eddy.