Analysis of Local Air–Sea Interaction in East Asia Using a Regional Air–Sea Coupled Model

Abstract

Abstract A regional air–sea coupled climate model based on the third regional climate model (RegCM3) and the regional oceanic model [the Princeton Ocean Model (POM)] is used to analyze the local air–sea interaction over East Asia in this study. The results indicate that the simulated sea surface temperature (SST) of the coupled model RegCM3–POM is reasonably accurate, and that the spatial pattern and temporal variation are consistent with that of the Global Sea Ice and Sea Surface Temperature dataset (GISST). The correlation between the SST and the atmospheric variables shows that the uncoupled model RegCM3 forced by the given SST cannot reproduce the real-time and SST lag correlation between SST and precipitation, and between SST and surface wind speed, whereas the relationship in the coupled model RegCM3–POM is reasonably accurate. RegCM3–POM reflects the air–sea interaction in the South China Sea and western Pacific Ocean, where the SST lead correlation is the inverse of the SST lag correlation between SST and precipitation, and strong winds bring warm water to the midlatitudes, so the correlation between wind speed and SST is negative in low latitudes and positive in the Kuroshio area. The uncoupled model fails to reproduce the effect of the atmosphere on the ocean. The further study on air–sea interaction in the South China Sea indicates that the earlier warm seawater corresponds to strong sensible heat flux, evaporation, precipitation, and weak net solar radiation, and the early strong sensible heat flux, evaporation, wind at the 10-m level, and weak net solar radiation cause the cold SST.