Study On The Response Of Climatic Change On Volume In Aksu River Valley, Xinjiang

Based on the temperature, precipitation, snowdays, snowdepth from the basic weather stations (1960-2006) in Aksu River Valley, and the observed runoff (1960-2003) of Aksu River, this paper analyzed the spatio-temporal distribution characteristic and tendency, and the response of runoff to climate change. The results are: the temperature have an ascending tendency, extent is 0.32℃/10a, the extent of winter is bigger, and the change is the most instability; the precipitation have an unconspicuous ascending tendency, but interannual change is not obvious; the results of Empirical Orthogonal Function (EOF) show: the originality temperature and precipitation matrix have a concurrent distribute characteristic with the whole climate, which mountainous area is the lower temperature and higher precipitation area, and the plain is opposition; the result of anomaly matrix show: the temperature and precipitation change of mountain area is steadyer than plain; the regression analyses of precipitation and altitude show: the two of them have Quadratic Function, through significant level of 0.0001; the most precipitation present at 2976.1m level, and the most precipitation is 315.2nm; from northwest to southeast the spatial distribute of snow is decreased, the largest snowdepth presents at Tomur-Hantengeri peak; there have 4 less snow period and 4 more snow period; the length of snow period lengthened with the altitude hoist.The runoff of headstream is ascending tendency, and, the coefficients of variation is 0.15, which reflected the Aksu River's supply is snow melting and precipitation; with the tendency verify of Mann-Kendall, the ascending tendency is obvious, which past the significant level of 0.05; moving-t test show that the break of runoff is consistent with precipitation's; Factor Analysis told us : mean annual temperature, winter precipitation and the largest snowdepth is the main factors which effected runoff more; then regression analysis ware done between mean annual temperature, winter precipitation the largest snowdepth, and runoff, mean annual temperature have the most obvious affect to runoff. When temperature and precipitation have 20% decrease respectively, the runoff have 5% increase; while, temperature and precipitation have 20% increase respectively, the runoff shows 5% decrease.