Abstract: Studying the spatial and temporal distribution of precipitation in the water receiving area of the water diversion project in central Yunnan Province is conducive to the scientific regulation and rational allocation of regional water resources. Based on the six-decade precipitation data of eight rainfall stations in the water receiving area, we investigated into the spatial and temporal distribution characteristics of precipitation in the area by using cloud model, Mann-Kendall test, wavelet analysis and collaborative Kriging interpolation method. The period from each June to August saw concentrated precipitation within the year, while from December to next February, precipitation was much less. The precipitation was unevenly distributed in summer and had the worst stability in August.The precipitation was even and small in winter. In addition, the annual precipitation decreased with a rate of 9.92 mm/10a which had abrupt changes and periodic fluctuations. The abrupt change points were concentrated between 1982 and 1992. And the precipitation experienced three cycles of wet-dry changes in the study period. The precipitation was also unevenly distributed in space. In spring, summer and autumn, precipitation in the south and the west was greater than those in the north and in the east, whereas in winter, the spatial distribution of precipitation was less regular. In summary, attentions should be paid to the flood prevention and drought relief in the water receiving area, the regional debris flows monitoring, and the prevention of summer drought.

Key words: precipitation, spatial and temporal distribution, cloud model, Mann-Kendall test, wavelet analysis, Central Yunnan Water Diversion Project