How Do Extreme Summer Precipitation Events Over Eastern China Subregions Change?

Spatiotemporal features of summertime extreme precipitation occurrences (EPEs) over eastern China subregions were captured by using observations from the CN05.1 daily data set and K-means clustering from 1961 to 2018. Five subregions including South China (SC), the Yangtze River Basin (YRB), the HeTao Area (HTA), North China (NC), and Northeast China (NEC) are identified, which is distinct from previous studies. The accompanying evolution of synoptic development are discussed, including the high rates of EPEs transfer from the YRB-type to the SC-type (18%), the HTA-type to the YRB-type (16%), the HTA-type to the NC-type (22%), and the NC-type to the NEC-type (25%). Intrinsic relationships that exist within these types of regional EPEs have not been recorded by previous studies. The intraseasonal evolution of summer EPEs shows a northward migration of the rainbelt influenced by the East Asian summer monsoon system. Moreover, temporal variations of regional EPEs from interannual timescales to long-term trends are examined.