【摘要】 山岳冰川在20世纪出现的全面退缩以及在最近20 a的加速消融是近年来国际冰川与全球变化研究的热点问题之一.庙尔沟平顶冰川位于天山山脉的最东段,南、北、东外围为气候十分干燥的荒漠戈壁,高山冰川是哈密绿洲主要的水资源,其冰芯记录包含有起源于这一地区的沙尘暴信息.因此,对该冰川的研究一直为人们所关注.基于2004年和2005年对庙尔沟平顶冰川的考察和取得的冰芯资料,初步探讨了庙尔沟平顶冰川的基本特征和过去24 a间的厚度变化.更多还原

【Abstract】 The shrinkage of alpine glaciers in the twentieth century is on a global scale.For a number of glaciers,the rate of shrinkage appears to have accelerated toward the end of the century.Located at the easternmost Tianshan Mountains in central Asia,Miaoergou Flat-Topped Glacier is surrounded by vast desert and gobi,where the Asia dust storms originate.Furthermore,the glaciers in this area are the major water supply for the extremely dry land.Therefore,the changes of these glaciers and their ice core records are widely concerned.On the basis of field investigations in 2004 and 2005 and the ice core records recovered from the summit of the glacier during 2005,this paper presents general characteristics of the Miaoergou Flat-Topped Glacier and its thickness changes over the past 24 years.The result shows that the glacial borehole temperature was around-7 ℃ at 10 m depth and-8.3 ℃ at the 60 m borehole bottom,indicating that this is a typical continental glacier.The net accumulation rate at the summit was approximately 200 mm\5a-1.Over the past 24 years,the glacier has evidently thinned around 5 m at the upper reaches.The ice core stratigraphy indicates that enhancement of the glacier melting may occur during the last 20 years.更多还原