A Study on the Characteristics of Summertime Extreme Precipitation Events over China in Recent 54 Years

The daily precipitation data collected from 571 stations in China for the summer (from June to August) from 1960 to 2013 are used to define seven extreme precipitation indices to investigate the characteristics of summertime extreme precipitation events over China. The results show that:(1) The spatial distribution of extreme precipitation events demonstrates remarkable regional differences. An increasing trend is found in the middle and lower reaches of the Yangtze River, South China, and Northwest China, while a decreasing trend occurs in Northeast China, North China, and part of Southwest China. Extreme precipitation events in China also show significant interannual and interdecadal variabilities with an increasing trend during the study period. An abrupt change occurred in the early 1990s. (2) Extreme precipitation events experienced a sudden change in the early 1990s based on M-K test results; extreme precipitation weakened (intensified) before (after) the sudden change. (3) The periodic oscillation of extreme precipitation events is dominated by the oscillation at the period of 15 years, followed by the secondary oscillation at the period of 7 years and the strongest oscillation occurred in 1998. (4) Extreme precipitation indices except CDD (consecutive dry days) are highly correlated with each other.