Tropical SST Response to Global Warming in the Twentieth Century

Abstract

Abstract The trend of sea surface temperature (SST) in the twentieth century is examined in observations and the Intergovernmental Panel on Climate Change (IPCC) twentieth-century simulations. The observed SST neither shows a clear signal of the enhanced equatorial response (EER) warming nor exhibits a clear trend of the El Niño–like warming in the last century. Similarly, the IPCC simulations show neither a clear EER warming nor an El Niño–like warming in the last century. Furthermore, the comparison of heat fluxes in model simulations of the global warming scenario and the twentieth century indicates that the aerosol cooling effect, opposite to the greenhouse gases warming effect, plays an important role in the twentieth century and explains the EER-like signal in the twentieth-century simulations. Therefore, a conclusion that the IPCC model simulations of the twentieth century are consistent with observations within the error bars as well as the future projection of the EER warming pattern in the global warming scenario are validated.