Tropical Atlantic sea surface temperature and heat flux simulations in a coupled GCM

Abstract

This paper contrasts the SST and heat flux errors in the Tropical Atlantic simulated by the CPTEC Coupled ocean-atmosphere General Circulation Model and its oceanic model forced by momentum and heat estimates. Comparisons between solar radiation estimated by satellite and measurements of PIRATA buoys have been made with the purpose of analyzing the impact of solar radiation in the simulation of SST in the tropical Atlantic. The radiative transfer model (ISCCP DX) has shown higher correlation with the buoys data than ECMWF ERA40 with larger differences over the eastern tropical Atlantic, where the numerical prediction models present difficulties in simulating the appearance of stratus clouds. The use of solar radiation based on satellite estimates and parameterized heat flux generated the best SST and surface heat fluxes. The stronger surface stresses generated by the CGCM contributed to generating an oceanic thermal structure in closer agreement with observations than the OGCM runs. Copyright 2006 by the American Geophysical Union.