Characteristics of Climate Variation in Qinghai Lake Basin During the Recent 50 Years

Under the background of global warming,based on the meteorological data at the four meteorological stations in Qinghai Lake Basin,the response on global warming in Qinghai Lake Basin during the recent 50 years was analyzed by using the methods of temperature anomaly and precipitation anomaly percentage,and combined with the change of water levels of Qinghai Lake.The results are as follows:(1) The annual mean temperature had the increasing trend with the linear rate of 0.28 ℃/10 a in Qinghai Lake Basin,and the temperature anomaly of the 30 days moving average indicated that the temperature fluctuated obviously in recent 10 years;(2) The precipitation in Qinghai Lake Basin in the past 50 years fluctuated in general with no significant increasing trend and its standard climate value was 379.1 mm;(3)The average annual evaporation was 895.4 mm in the whole Qinghai Lake Basin;(4) Warming and dry in the Qinghai Lake Basin led to increase of the Lake evaporation,which resulted in water level of Qinghai Lake decline in nearly 50 years with the rate of 0.79 m/10 a.