Evaluation and Analysis of RegCM3 Simulated Summer Rainfall over the Huaihe River Basin of China

This study evaluates the ability of the Abdus Salam International Center for Theoretical Physics (ICTP) version 3 Regional Climate Model (RegCM3) in simulating the summer rainfall amount and distribution and large-scale circulation over the Huaihe River basin of China. We conducted the simulation for the period of 1982–2001 and the wet year of 2003 to test the ensemble simulation capacity of RegCM3. First, by comparing the simulated rainfall amount and distribution against the observations, it is found that RegCM3 can reproduce the rainfall pattern and its annual variations. In addition, the simulated spatial patterns of 850-hPa wind and specific humidity fields are close to the observations, although the wind speed and humidity values are larger. Finally, the ensemble simulation of RegCM3 for summer 2003 failed to capture the spatial distribution and underestimated the magnitude of the precipitation anomalies, and the reasons are analyzed.