基于TM影像天山北坡地表反照率反演方法的研究

地表反照率是气候模型和地表能量平衡方程中的重要参数。基于6S模型估算地表反照率,忽略了地形起伏的影响,不同波段组合的地表反照率也有待进一步研究。本文选取干旱区典型流域——天山北坡三工河流域为研究区域,以TM影像为数据源逐步进行地形校正、大气校正等,从而提取窄波段地表反照率。在此基础上,根据亮度、绿度、湿度3个特征变量的物理意义,以各波段能量权重为转换参数对窄波段地表反照率进行组合,实现研究区宽波段地表反照率的反演,得出基于不同波段的物理意义的地表反照率。

Study on Asimulation of Surface Albedo in the Northern Slope of Tianshan Mountains Based on TM Image

The surface albedo is an important parameter of the climate models and surface energy balance equation.The study of surface albedo is based on 6S model neglecting the impact of the terrain.The total short wave albedo can be calculated in the normal case.However,different band combinations of surface albedo are often ignored.This paper chooses the Northern Slope of Tianshan Mountains as the study area and the TM image as the data source,and conducted topographic and atmospheric correction and spectral calibration.Land surface narrowband albedo can be achieved.According to the different physical meaning of the band of satellite,the broadband surface albedo can be calculated based on the band weights.It was found that it was reasonable to use different bands to achieve the albedo of different features.Meanwhile we also analyzed spatial distribution pattern of surface albedo of the different land-use in Sangong River watershed.