Abstract: The annual and seasonal precipitation and temperature from 1951 to 2003 in the Hanjiang Basin were analyzed to obtain the temporal and spatial trend by using the MannKendall trend test and the spatial interpolation method. The precipitation, temperature in the upper Danjiangkou reservoir basin and the temperature in the northern hemisphere were compared and analyzed to obtain the relationship between them. The results indicate that at the α=0.1 significance level there is no trend of the precipitation in most parts of the Hanjiang basin, but the trend of the temperature is upward. In the upper basin the precipitation had a climate jump in 1991 when the precipitation changed from the wet period in 1980s to the dry period in 1990s. The average precipitation in 1980s is 9.7% more than the mean value of 1951~2003, while in 1990s is 11.6% less than that value. The average temperature in 1990s is 0.3℃ higher than the mean value of 1951~2003, in the same period the average temperature of the northern hemisphere is 0.3℃ higher than the mean value of 1951~2003. The temperature in the upper basin is increased, while the precipitation is decreased as the temperature increases in the northern hemisphere. The results will help in further studying the impact of the climate change on water resources and the flood prevention in the Hanjiang Basin. It will also provide scientific references for the middle route of southtonorth water diversion project in China.

Key words: trends analysis, climate jump, MannKendall, Hanjiang Basin