El Ni¿o is a major interannual climate signal resulting from complex ocean-atmosphere interactions in the Tropical Pacific. Its impact on the SST (Sea Surface Temperature) of the Southern Ocean through an atmospheric bridge are investigated with an atmospheric general circulation model coupled to a slab mixed-layer ocean. Simulated results suggest that SST changes in the mid- and high-latitude oceans and the Tropical Indian Ocean can be explained by modifications of heat-flux exchange at the air-sea interface. For the Tropical Atlantic, however, the discrepancy is large, indicating that the oceans dynamics are not negligible. ¿ 2000 American Geophysical Union