近50年来新疆天山山区水循环要素的变化特征与趋势

天山山区由于其特殊的地理位置与高海拔,成为新疆地表径流的主要产流区域。近几十年来,全球平均气温的持续上升对该区域气温、降水、径流等水循环要素产生重要的影响。根据天山南北坡有关水文气象台站的观测资料,系统地分析了该区域1960年代以来各水循环要素的变化特征与趋势。结果表明,受全球变暖的影响,1980年以来整个天山地区气温和降水均呈明显的上升趋势,其中10 a气温的升幅更为显著;对于降水而言,天山南坡降水增幅大于北坡,而南坡的西段是近10 a降水增幅最大的区域。受气温上升与降水增加的影响,天山地区出山径流总体上呈增加的趋势,其中,近10 a天山南坡中西段河流出山径流量增幅最为显著,平均增幅在30%以上。

Characteristics and Trends of Changes on Water Cycle Factors in the Tianshan Mountainous Area since 1960s

The Tianshan mountainous area have being one of the main contributing regions of the surface runoff in Xinjiang because the especial geography and high altitude.Global warming brings an important impact to the water cycle factors such as air temperature,precipitation and runoff and so on in the area in the recent decades years.Characteristics and Trends of Changes on some water cycle factors in the Tianshan mountainous area since 1960s are analyzed based the observational data of precipitation,temperature and runoff at 38 hydrometric stations in the Tianshan mountainous.The result indicated the temperature and precipitation in the area presents an increasing trend since the 1980s,especially the rise extent of air temperature is more obvious in the recent ten years owing to the impact of Global warming.But As for precipitation,its increasing extent in the south slope of the Tianshan Mountains is larger than that in the north slope and the that on west part of the south slope is the largest in the recent decade.Impacted by the temperature rising and the precipitation increasing,the runoff from the Tianshan Mountainous area has been presenting the increasing trend,and the runoff in the mid and the west parts of the south slope in the recent decade is the most obvious,which average increasing extent is above 30%.