Impact Of Climate Change To Water Resource On The Upper Reach Of Kaidu River Basin,Xinjiang

Understanding climate change is vitally important as such changes coupled with its impact on hydrology and water resources have caused many influence to ecology,environment and society.Glacier and snow are not only indicators of climate change,but important water resources for life and production.It is,therefore,significant to explore climate change and its influence in hydrological processes in response to economic development,people's life and even social stability.Duo to the great impacts of climate on the arid area in northwest China,the first part of this study is to analyze variation characteristics of precipitation and temperature.The results indicate that: An increasing trend of temperature is found in study area during the period of 1958-2013.And there is a significant increasing trend of temperature in summer and autumn.Annual extreme precipitation,spring mean precipitation and spring extreme precipitation all present a decreasing trend,while an increasing trend of mean precipitation is shown in other seasons.There is an increasing trend of maximum temperature with the time delayed during 1990 to 2013.On the contrary,a decreasing trend of minimum temperature with the time in advance is found in the same period.Meanwhile,the period of annual snowmelt(temperature>0?)has been extended.According to the regional climate change,we analyze the trend of future climate.It is shown that: compared with the current,future temperature presents a rising trend with RCP4.5 and RCP8.5 emission scenarios.We also find that there has a different trend of precipitation in different season.On the basis of MODIS snow data,exploring the variation characteristics of snow.We can draw the conclusion that: During 2001 to 2013,there exhibits a decreasing trend of snow-covered area in low elevation and high elevation,with an increasing trend of middle altitude.However,an increasing trend of snow-cover area is found in study area during the period of 2001-2013.This study constructs and improves snow-melt runoff model(SRM)based on the analysis of climate change.With RCP4.5 and RCP8.5 emission scenarios,simulation of runoff process and component shows that: Years of snowmelt runoff of total runoff is in secondary status with rate of 35%.However,the snowmelt runoff accounts a dominant position with the rate of 56.4% and a rate ranging from 46% to 48% of snowmelt in autumn and winter.There exists a slight decreasing trend in total runoff,but a significant increasing trend of snowmelt runoff during 2001 to 2013.A certain decreasing trend of runoff is found in summer and a significant trend in spring under RCP4.5 and RCP8.5 emission scenarios.Compared with RCP4.5,we can see more obvious process and larger extent change of runoff with the RCP8.5 emission scenarios.Overall,there has little influence of annual total runoff with two emission scenarios.However,two emission scenarios have resulted a significant change in the distribution of annual runoff.There would have a great influence in socio-economic,ecological environment with the annual redistribution of runoff caused by climate change.