Dynamical characteristics of the Cape Verde frontal zone

Abstract

We analysed historical data (Fraga and Manríquez, 1974; Manríquez and Fraga, 1978) to investigate the relation between the position of the Cape Verde frontal region and the geostrophic velocity field in summer and winter. The position of the front is well determined in the plotting of the salinity and nutrient distributions in isopycnic coordinates. The geostrophic velocity shows sharp gradients as a function of density and distance on sections normal to the coast. These gradients are reasonable well correlated with the frontal position and indicate the existence of strong meridional interleaving. The flow field relative to 400 m illustrates this interleaving as fluctuations on a westward mean flow. The surface temperature distribution undergoes very large latitudinal displacements but may help to locate the presence of north and south surface water.