Fifty-year Climate Change And Its Effect On Annual Runoff Volume In The Headwaters Of The Tarim River Basin, China

With the globe temperature increasing ,the temperature of the three Water Resources in the Headwaters of the Tarim River have the increase tendency,then the climate change must to affect the runoff. This paper based on the meteorology and hydrology data near 50 years of the Water Resources in the Headwaters of the Tarim River and has discussed the climatic change and its influence on the runoff. The results show that:1,The runoff overall presents the increase tendency of the three Water Resources in the Headwaters of the Tarim River in the past 50 years, and there was undulation process in the period, especially manifested after the 90's, the high water years apprared more times; using Kendall analysis and Hurst index are applied to analyze the tendency and persistence of natural runoff of three resources. the runoff presents the increase tendency of Aksu River Basin, the increase of tendency and persistence are very obvious; the runoff presents the decrease tendency of Hotan River Basin,but the tendency isn't obvious,in the future the randomicity is more obvious; the runoff presents the increase tendency of Yarkend River Basin,and the increase tendency isn't obvious,the change of runoff has not only randomicity but persistence.2,Make the correlation analysis to the runoff and the rainfall and the temperature, with the temperature increasing by the age,it is influence the runoff more and more remarkabale. the temperature ascensionhas accelerated the ablation of snow and ice resources in mountainous area .Thus it enlarged the supplies to amount of runoff . But simultaneously it caused the transpiration to increase, added consumption of the surface fresh water resources. It can weaken the increase of water which come from the mountainous. but the growth speed of the precipitation is farer than the speed of the transpiration,so the transpiration rate increase also is insufficient to cause the runoff reduction.the runoff3,The sencitivity respond of the runoff to the climate change show that, runoff would reduct in different degrees when it in the same temperature but the rainfall increase.The rainfall increase will lead to lower the temperature ,so that the snow and ice melt water will reduct.Both the results,runoff increased unconspicuously.