Spatio-temporal variation of precipitation in the Three Gorges Reservoir Area from 1960 to 2016

Under the background of global warming, regional precipitation changes obviously, which has an important impact on the ecological environment. this paper investigated the change characteristics of 11 precipitation indexes by using linear trend rate, MK trend test and spatial interpolation methods, based on the daily precipitation data of 23 weather stations in the Three Gorges Reservoir area and its surrounding areas. The results showed that six precipitation indexes (PRCPTOT, CDD, CWD, R10, R20 and RX5day) in the Three Gorges Reservoir area showed a decreasing trend, and CWD showed a significant decreasing trend with a decreasing rate of 0.20 d/(10 a). Five precipitation indexes (R50, R95p, R99p, RX1day and SDⅡ) showed no significant upward trend. The spatial distribution pattern of PRCPTOT, R10, R20, R50 and RX5day showed a high value in the central part and low in the southwest and northeast part. CDD and SDⅡ gradually increased from southwest to northeast, while the spatial pattern of CWD, R95p, R99p and RX1day was not obvious. Compared with 1960-2003, the variation range in extreme precipitation indexes such as R50, R95p, R99p, RX1day, RX5day and SDⅡ from 2004 to 2016 was greater than that of the other indexes.