【摘要】 数字高程模型(DEM)广泛用于计算地形因子、辅助遥感影像的信息提取及参与地理信息系统(GIS)的空间分析操作。本文主要介绍了 DEM 在西藏那曲雪灾遥感信息提取中一些技术和方法的应用。结果表明,DEM 不仅可以消除由于地形因素的影响造成的像点太阳高度角偏差,提高积雪信息提取的精度,而且还是判别成灾状况的重要因子,是那曲雪灾遥感监测系统的重要部分。更多还原

【Abstract】 The Digital Elevation Model<DEM>are widely used for calculating terrain parameters,as- sist information extraction from remote sensing images and as a factor in spatial analysis operation of Geograph Information System(GIS).Some techniques and methods of application of DEM to the extraction of snow disaster information from NOAA/AVHRR images in Nagqu area of Xizang was introduced in this paper.The research results showed that it could not only remove the influence of terrain factors on solar zenith angle to improve the accuracy of extracting snow disaster information,but also be used as an important assistant factor of assessment of snow dis- aster.So DEM is an important part of the system of snow disaster monitcring and assessment by remote sensing.更多还原