Accuracy assessment of MSWEP over mainland China

The accuracy assessment of global gridded precipitation products is the first step in local application. Based on the daily precipitation observation data of 824 weather stations in China during 1979-2015, this study intends to evaluate quantitatively the accuracy of newly released Multi-Source Weighted-Ensemble Precipitation (MSWEP) products in China by using a variety of indicators such as relative bias and correlation coefficient. Moreover, a corrected Mann-Kendal trend monitoring method was used to analyze the reliability of MSWEP products in trend analysis of precipitation. The main conclusions show that:① Precipitation estimated from MSWEP is higher than that of the gauged precipitation in China. However, there is an underestimate in the North China region. ② MSWEP daily rainfall data have overestimation and underestimation of slight-precipitation and heavy-precipitation events, respectively. ③ There is a good relation between monthly/annual gauge precipitation and MSWEP. ④ There is an obvious spatial difference between the trends of annual precipitation based on MSWEP and site observations in China. However, in spring, autumn and winter, the spatial distribution of the trend is in good agreement.