利用祁连山区水文站和气象站的观测数据,分析了近50年河西走廊西部疏勒河流域山区的气候变化及其对出山径流的影响。结果表明,受全球变暖的影响,疏勒河山区气候持续向暖湿转化,且各季气温均呈持续的上升趋势,山区降水量总体上亦呈增加趋势,年际波动比较剧烈。在各季降水量中,除夏季外其他各季降水量的增加比较显著,海拔3 000m以上中高山地带夏季降水量变化不大,3 000m以下中低山地带夏季降水量略有减少。受山区降水,尤其是3 000m以下中低山地带的降水量显著增加与气温上升所引起的冰雪融水补给的影响,疏勒河出山径流呈持续的增加趋势。由于夏季降水量并未增加,在年径流总量中所占比重最大的夏季径流量的增加主要是由于气温上升所引起的冰雪融水补给的增加所致。
The characteristic of climate change in the mountainous region of the Shulehe River basin in the past 50years and its effect to runoff are analyzed using the observational data at the relational hydrological and meteorological stations.The results show that the climate in the region has become more and more wet and warm in the past 50years because of the influence of global warming.The mean temperature of year and every season have been presenting a rising and increasing trend in the region.The precipitation of whole year and every season except for summer also all have been a rising and increasing trends in the region as a whole,and the annual fluctuation of precipitation variation is quite obvious,especially for theprecipitation during flood season.The mountainous runoff of the Shulehe River basin also has been an increasing trend because the precipitation in the zones which elevation are below 3 000mare ice and snow melt-runoff in the high elevation zones above 3 000mare obviously increase.The reason of summer runoff increasing main is the increasing of snow and ice melt water supply from the zones above 3 000mbecause the summer precipitation is not increase.