利用多时相DEM数据的冰雪覆盖体量变化计算方法研究

An Approach on Calculating Firn Volume Change from Multi-temporal DEMs

提出了利用同一研究区不同时相且无地质灾害发生情况下数字高程模型(DEM)的差异来计算冰雪覆盖体量变化的方法。设计实现了两种DEM主要表达形式(规则格网DEM和TIN)的冰雪覆盖体量变化计算方法,提出基于三维道格拉斯-普克算法的DEM数据综合方法,减少离散点数量,从而提高建立TIN网的速度以及体积变化计算速度。最后以天山乌鲁木齐河流域数据为例对两种计算方法进行了实验验证。

This paper firstly suggests a method of calculating the volume change of the firn based on the DEM data sets which are for the same area,acquired at the same season,but in different years,and during this period no obvious geological disasters occurred in the studying area.Secondly,two methods for calculating the volume change of the firn are introduced： one is based on the regular square grids（RSG）,another uses the triangulated irregular network（TIN）.The verification experiments calculated from the same original DEM data acquired in 1962 and 1990 respectively for the drainage area of Urumchi River Basin in Tianshan Mountain are introduced and have proved that it is feasible and accurate to calculate the firn＇s volume change in the study area using DEMs of different time phases where no obvious geological disasters have occurred.