The Effect of Lateral Boundary Treatment of Regional Climate Model on the East Asian Summer Monsoon Rainfall Simulation
区域气候模式侧边界的处理对东亚夏季风降水模拟的影响

In this paper two different lateral boundary treatments have been designed to study the effect of lateral boundary on the East Asian summer monsoon rainfall with SUNYA-ReCM. It is found: (1) when the lateral boundary buffer zone is too small compared with relatively large model domain, there exists a somewhat discontinuous behaviour at the edge of the buffer zone. (2) An even wider buffer zone with considering the different influences of various scale forcing in the vertical can obtain even smoother transition from boundary to model regime, moreover, because this method reduces the role of regional climate model on large-scale fields simulation, regional climate model can get more realistic factors which have significant effects on the East Asian summer monsoon rainfall, such as southwest monsoon, South China Sea monsoon and subtropic high, and then get a better simulation of summer monsoon precipitation both in quantity and in the sudden jump of rainfall belt.