An Improved Land-Surface Albedo Algorithm With DEM in Rugged Terrain

The influence of topography on land-surface bidirectional reflectance and albedo should be considered in rugged terrain. However, land-surface albedo algorithms neglect topographic effects, leading to errors in estimating the albedo in rugged terrain. This letter investigates the Angular Bin (AB) algorithm of land-surface albedo and shows that it should be improved when albedo is estimated in rugged terrain. The Terrain AB (TAB), an improved algorithm for albedo estimation with the AB algorithm and digital elevation model (DEM) data set, is presented in this letter. The accuracy and performance of the TAB algorithm was investigated by using the simulated DEM and Bidirectional Reflectance Function as well as the MODIS daily reflectance of the Heihe River Basin. The results show that the TAB algorithm has a better albedo estimation performance in rugged terrain and gives an acceptable accuracy.