Abstract:In this paper, based on the comparison between Mid-Holocene (6 ka BP) experiment and the RCP8.5 experiment performed in CMIP5, the spatial pattern and causes of rainfall evolution in the East Asian summer monsoon region under different warming scenarios are studied.The study results show that there are significant differences in the spatial patterns of rainfall evolution in the East Asian summer monsoon against the two warming backgrounds.During the mid-Holocene warm period dominated by the enhancement of summer orbital radiation, the pattern of rainfall evolution in the East Asian summer monsoon region bore a meridional “tripole” structure.However, the future strong warming dominated by the increase of atmospheric CO2 concentration was dominated by the overall increasing pattern.In addition, the moisture budget decomposition of water vapor shows that the dynamic component of the rainfall change in the East Asian summer monsoon was dominated by the monsoon circulation, which is represented by the meridional “tripole” structure, while its thermodynamic component depends on the atmospheric specific humidity dominated by the temperature, which is represented as a spatial distribution consistent with the temperature change.The change of rainfall in the East Asian summer monsoon region was dominated by the change of dynamic component during the warm period of the Mid-Holocene, but later it was dominated by the change of thermodynamic component under strong warming.