Study On Climatic Variation And Its Effect In Recent 45 Years In Ebinur Lake Basin Of Xinjiang

Based on the monthly air temperature, precipitation, evaporation and wind speed data during 1961-2005 at 5 basic meteorological stations in Ebinur Lake basin, the climatic variation is shown by the tendency analysis, period analysis and abrupt analysis., Based on the surface runoff observed data during 1961-2000 in Ebinur Lake basin and the area covered by water of Ebinur Lake during 1950-2005, response of surface runoff as well as the area covered by water to climate variation are analyzed. The major conclusions of this study are as follows:(1) The annual mean and the four seasons air temperature are increasing, especially most obvious by the 1990s. The variation of in maximum and minimum temperature in Ebinur Lake basin is asymmetric, especially most obvious in summer, autumn and winter. The annual mean precipitation and precipitation in spring,summer and winter have been increased since 90s; annual evaporation and each season,but the 90's annual and each season evaporation comparatively 80's appear to decrease, it is opposite with the air temperature evolution tendency; the average wind speed of year and the four seasons presents decreasing tendency. Climate has changed obviously in 1990's, which the air temperature and precipitation has increased; evaporation and wind speed have decreased.(2)The spectral analysis is used to investigate the air temperature, precipitation, evaporation and wind speed in Ebinur Lake basin; it is found that there is a 2.4 and 8.8 years periodicity in the air temperature. The precipitation appears the cycles of 6.3 and 2.9 year. The evaporation appears the cycles of 6.7,4.4 and 3.3 year. Meanly, it is found that there is not periodicity in the wind speed. In this paper, some abrupt changes of the air temperature , precipitation, evaporation and wind speed in Ebinur Lake basin have been tested using Mann-Kendall method. It is showed that the air temperature contained abrupt changes from cool to warm in 1976. It is found that the abrupt change of precipitation occurred in 1969, hereafter the precipitation become more. The abrupt change of evaporation occurred in 1981,...