The surface Guinea Current variability from satellite data

Abstract

The advent of satellite measurements over the recent decades has made a great contribution to the understanding of near-surface circulation and particularly to the understanding of the surface Guinea Current (GC) along the northern coast of Gulf of Guinea (GG). This study focuses on the GC variability and its relationship with the coastal upwelling from 19 years (2000-2018) of GEKCO (Geostrophic and Ekman Current Observatory) satellite data. These data reproduce the major patterns of GC along the northern GG. The GC flows eastward with a strong spatial and temporal variability with maximum intensity during boreal summer in the east of both Cape Palmas and Cape Three Points. This study showed that the geostrophic current is the dominant component of surface circulation. The Ekman current being lower component contributes also to the intensification of GC in summer. Our study showed that the intensification of GC in summer results from the concomitant acceleration of the geostrophic and wind-driven Ekman currents. Our work highlights the main patterns of GC and its role in the coastal upwelling as limiting it in the east.