Seasonal behavior and the plume evolution of the Cabo Frio coastal upwelling, Brazil

Sato, C. M.¹,²; Calado, L.²
¹ Universidade Federal do Rio de Janeiro – COPPE
¹,²Marinha do Brasil - Instituto de Estudos do Mar Almirante Paulo Moreira


The southeast coast of Rio de Janeiro state is primarily dominated by upwelling of deep water due to the interaction between the Tropical Water and the South Atlantic Central Water (SACW). The topology of the area plays an important roll on this upwelling system. The Cabo Frio region exhibits an abrupt change of the coastline orientation from the NE-SW to E-W direction. Additionally, there is a wide continental shelf ranging from 80 km at Cabo Frio to 150 km outside of Guanabara Bay. The SACW rises near Cabo Frio and propagates to the Southwest, reaching Guanabara Bay and offshore regions.

This work consists of a four-year (2007-2011) simulation of the sea surface temperature to characterize the seasonal behavior of the coastal upwelling in the Cabo Frio region and its plume propagation. The numerical simulation was performed using ROMS forced by the 6-hours Reanalysis II wind fields (NCEP/NOAA). A high-resolution, 1 km grid is used to resolve the area between Cabo Frio and Guanabara Bay.

The model results are compared with the MUR-SST satellite data. Both the model and satellite data showed the same trend of the sea surface temperature fields during the whole period modeled. We find that coastal upwelling events are more frequent and intense during summer and spring seasons when the northeast wind is more persistent. The coastal upwelling plume reached distances of about 140.6 km alongshore, towards the Guanabara Bay, and 36.5 km offshore, from its rising region.