Extreme Summer Precipitation Events in China and Their Changes during 1982 ~ 2019

Abstract

This work analyzed the spatial and temporal variations of the extreme precipitation over China during the period 1982 to 2019, based on GPCC data. Meanwhile, the spatially clustering characteristic of China is evaluated based on the trends of summer precipitation through K-means. This is the first to clustering based on the trend of summer precipitation. The results indicated that the spatial distribution of MK trends for the summer precipitation indices over China during 1982 ~ 2019 shows increasing and decreasing trends in different regions. The extreme precipitation has been found mainly in Pearl River Basin, Southeastern River Basin, Huaihe River Basin, and the lower reaches of the Yangtze River. The risk of floods in SERB (the Southeastern River Basin), especially those caused by short-term heavy precipitation, may increase in recent decades. Four clusters are identified through K-means, which can be named as stable (59%), extreme wetter (5%), dryer (19%), and wetter (17%) zones. Combining the spatial distribution of the multi-year average of precipitation indicators and four clusters, the ‘wet to wetter and dry to dryer’ is found in China summer precipitation.

Keywords: extreme precipitaion, cluster analysis, China