青藏高原腹地羌塘双湖地区羌塘1号冰川物质平衡观测研究

The project is planned to carry out field observations, including glacier mass balance, energy balance, glacier surface absolute elevation changes and hydro-meteorological elements, at Qiangtang No.1 glacier in Qiangtang Shuanghu region in Tibetan Plateau hinterland,and combine with an energy balance based distributed mass balance model,to analyze the differences of mass balance due to use different observation mathods by glaciological and high-precision DGPS measurement,to clarify the basic characteristics of glacier mass balance and energy balance in this region, and to explore the effects of terrain information, including slope, aspect and elevation, on glacier mass balance. This not only helps to understand the features of glacier mass balance in this region, but also to explore the relationship between glacier changes and lake expansions. So this project has important theoretical and practical significance.

本项目拟在青藏高原腹地羌塘双湖地区羌塘1号冰川开展冰川物质平衡、能量平衡、冰川表面绝对高程变化、水文气象要素的野外强化观测，并结合基于能量平衡的分布式物质平衡模型，分析传统的冰川学方法和高精度的DGPS测量两种方法观测物质平衡的差异，阐明青藏高原腹地双湖地区羌塘1号冰川物质平衡和能量平衡的基本特征，探究地形信息（坡度、坡向和高程）对羌塘1号冰川物质平衡的影响。这不仅有助于了解青藏高原腹地羌塘地区冰川物质平衡特征，而且对探讨青藏高原腹地冰川变化与湖泊扩张具有重要的理论意义和现实意义。

通过羌塘1号冰川区的实地观测，获取了羌塘1号冰川及其南支和北支北川的物质平衡特征（平衡线高度、积累区面积比率和积消等值线图），根据实地观测结果该冰川处于物质亏损状态。过去三年羌塘1号南支、北支及整体的累计物质亏损分别为-2344，-1796 和 -2011 mm. w.e. 通过分析对比南北支冰川消融量随海拔的分布，发现相同的高程带南支冰川的消融强于北支，但由于北支冰川5700m以上，面积较大，因此导致南北支冰川物质平衡有教明显的差异。通过羌塘1号冰川末端的水文观测发现，南北支冰川末端的冰川径流量日变化过程极为相似，北支由于面积较大，其冰川流量略大于南支冰川末端径流量。通过北支冰川7月至10月的水文观测值，估算北支冰川在消融期的冰川径流并与同期冰川的净物质平衡量进行对比，发现冰川末端径流主要来源于冰川物质亏损，同期降水对径流的贡献仅占总流量的5%左右。通过冰川顶部，南支和北支冰川中部的气象观测，发现该区主要受西风影响。通过对南支冰川的DGPS测量，发现测高法和传统的物质平衡观测法所得结果基本接近。