Changes in spatiotemporal pattern of precipitation over China during 1980–2012

Abstract

A gridded data set of daily precipitation records together with percentile-based precipitation indices was utilized to analyze changes in spatiotemporal pattern of precipitation across China in the last 33 years (1980–2012). Identifiable changes in precipitation structure and distinctive spatial variations in precipitation trends were detected at both annual and seasonal timescales. Generally, a slight but discernable increasing trend was observed in annual precipitation, and precipitation increased during summer and winter but decreased in spring and autumn. In addition, great differences were distinguished in the aspects of precipitation day, precipitation amount and precipitation duration among light, moderate and heavy precipitation. Additional analyses of extreme events including wet day, very wet day, daily maximum precipitation, short dry period and long dry period, were also performed, which indicated an upward trend in days with more precipitation. Study of contributions to the precipitation day and amount showed that light and moderate precipitation contributed greatly to the precipitation day while moderate and heavy precipitation contributed greatly to the precipitation amount. Finally, it could be concluded that it was getting drier in southeast China but wetter in southwest China, with severe droughts in northwest China being relieved during the last 33 years.