Analysis on Precipitation Spatial and Temporal Variation Features of Xuchang City From 1953 to 2016

According to the daily meteorological precipitation data of Xuchang city from 1953 to 2016, using the linear trend estimation, the accumulative anomaly, the sliding t test, the M-K mutation analysis method to analyze the annual precipitation and the spatial and temporal variation features of four-season precipitation.The results show that the average annual precipitation is 726.34mm of Xuchang city,the max annual precipitation is 1132mm (1961), the minimum annual precipitation is 413mm (1964), and the annual precipitation trend rate is-10.3 mm/10a from 1953 to 2016.Precipitation distribution of a year is seriously uneven.It is mainly concentrated in summer and autumn.Precipitation decreases in spring,summer and winter, and increases in autumn.There are no obvious precipitation mutation years of in spring,autumn and winter.The summer precipitation obvious mutation time is from 1998 to 2007,and the annual precipitation mutation point is 2010.