Abstract:Based on high resolution (0.5°×0.5°) daily precipitation data from 1961 to 2010, the spatio temporal characteristics of summer rainfall over the eastern, western and whole Yunnan Guizhou Plateau (hereafter YGP) were investigated. Besides, using the European Centre for Medium Range Weather Forecasts (ECMWF) Interim Reanalysis data (ERA Interim hereafter) from 1979 to 2010, we examined the average water vapor flux over the YGP in summer. The results show that the distribution of climatological annual precipitation in YGP is uneven. A dry center is located in the middle of the western YGP and it increases gradually southward and westward. Meanwhile, precipitation over the eastern YGP decreases from southeast to northwest. The YGP is divided into eastern YGP (EYGP) and western YGP (WYGP). The precipitation over the two parts increases with higher increase rate of rainfall. In terms of water vapor transport, it mainly transports from southern and western boundaries to northern and eastern boundaries of the YGP. The whole YGP acts as a water vapor source annually. The net water vapor is positive in EYGP but negative in WYGP. The precipitation, however, increases over both regions. The water vapor over the WYGP is mainly from the northern part of the Bay of Bengal, the northern South China Sea and the area from the Hengduan Mountains to Sichuan Basin. As for the EYGP, the moisture is mainly from the northern South China Sea and western Sichuan Basin.