The influence of ENSO on air-sea interaction in the Atlantic

Abstract

Observations and model experiments are used to investigate the influence of El Niño/the Southern Oscillation (ENSO) on air-sea interaction in the north Atlantic, Gulf of Mexico and Caribbean Sea. In one experiment, observed sea surface temperatures (SSTs) in the tropical Pacific are specified as boundary conditions in an atmospheric general circulation model (AGCM), while SSTs over the remainder of the global oceans are simulated by a mixed layer model. The observed warming in the tropical North Atlantic and cooling in the Gulf of Mexico in the winter/spring after ENSO peaks is well simulated by the model. Prior to the basin wide warming, latent heat fluxes generate negative SST anomalies in the Caribbean during August-October. Ocean-atmosphere coupling outside of the tropical Pacific significantly enhances the warm season atmospheric response to ENSO in the Caribbean region.