Abstract:

The meteowlo~cM data from seven representative stations around the Lake Qinghai during 1959—-2005 were used to investi-·gate climate change of the Lake Qinghai watershed by mea／18 of Thiessen polygon method．the climatic tendencies were analy~d by Mann—Kendall test．Th e results are as follows：(1)In the recent 47 years，the decadal variation of precipitation is significant，there are ascending tendencies in the 1960s，1980s and 1990s，while precipitation in the 1970s shows downward trend，and there are ascend·ing trend of long—term change in summer and annual precipitation respectively；(2)Th e ascending tendency of temperature is remark-able．and the average temperature during 1987—2000 increases 0．79℃ compared with that during 1961—1986；(3)The tendencies of annual and seasonal evaporation present positive trend；(4)Th e precipitation has a significant correhtion with the lake—level and runoff of the Buha River and the Shaliu River．Based on nine years scale，the precipitation in autumn will increase in the coming 5 years，this may decrease the magnitude of the decline of the lake—leve1．

Key words: the Lake Qingl~i Watershed, temperature, precipitation, evaporation

摘要：

选取青海湖流域内及临近7个气象站点，对各站1959—20o5年的降水和气温数据采用泰森多边形法进行了计算，并运用Mann—Kendall方法对其变化趋势进行了分析，同时对流域近47 a的气候变化与青海湖水位变化做了相关分析。结果表明：①青海湖流域近47 a来降水存在明显的阶段性变化，20世纪60年代、80年代、90年代降水都呈上升的趋势，70年代为下降趋势；同时年、夏季降水有增加的趋势。② 同时期气温存在显著的上升趋势，尤其是冬季增温显著，年变化倾向率达到0．53~C／10 ft．，1987—2000年与1961—1986年相比，平均气温增加了0．79℃ ，显著高于全国水平。③ 青海湖流域近47 a来春、夏、秋、冬陆面蒸发变化倾向率均为正值，夏季陆面蒸发增加趋势显著，年变化倾向率为4．17 mm／10 a。④ 流域降水量对湖水位的年变化、布哈河径流、沙柳河径流有着显著的影响；在9 a尺度上讲，未来5 a流域秋季降水处于上升阶段，湖水下降会有所减缓或者回升。

关键词: 青海湖流域, 气温, 降水, 蒸发