Abstract:
To understand the impact of soil moisture on summer climate over China, the regional climate model RegCM3 was forced by “observational” soil moisture data from the Global Soil Wetness Project (GSWP). The forcing of soil moisture produces a more realistic summer climate. Improvement is evident in the spatial patterns of both precipitation and surface (2 m) air temperature, as well as the daily variation of precipitation and surface air temperature in summer. The interannual variations of precipitation and temperature are also improved, as indicated by the increased correlation coefficients. The improvement is however regiondependent. The model response indicates that the sensitivity of surface air temperature to soil moisture is stronger than that of precipitation. The modeled results suggest that the soil moisture may serve as a useful forcing factor in improving the seasonal forecast skill over China.