Upwelling off the Brazilian coast

Several mechanisms can drive vertical velocities in the coastal ocean, including wind-forcing and through gradients in the vorticity field generated by flow-topography interactions. In this work, we studied the two major upwelling systems off the Brazilian coast: Cabo Frio and Cabo de Santa Marta.

Using a combination of satellite remote sensing data and analytical theory, we addressed the effects of wind-forcing and flow-topography interaction in the vertical transports over the continental shelf, and with this work, we learned that on larger scales, the sea surface temperature variability along the coast is mainly controlled by wind-driven upwelling, while upwelling due to flow-topography interaction (e.g. flow around capes and perturbations of the coastline) is responsible for the smaller scale sea surface temperature variability.

In the vicinity of capes and coastal features, topographically driven upwelling plays a significant role, and its vertical transports can be as large as the wind-driven transport. The enhancement of upwelling in these regions is known to have a major impact on the local fisheries.