Advanced Remote Sensing, 2nd Edition

19.4. Optical remote sensing techniques

Unlike microwave remote sensing, the penetration depth of visible light into snowpack rarely exceeds a few centimeters. Thus, there is no direct physical relationship between the snow depth and the snow reflectivity. However, for most types of terrain surfaces, owing to the influences of the vegetation and topography, the fraction of the land surface covered by the snow increases with increasing snow depth. The surface reflectance changes until the snow depth reaches a value that masks the surface completely. This relationship between snow depth and the surface reflectance of fractional snow cover is significant for shallow to moderate snowpacks, providing a way to retrieve snow depth from the reflectance ...