A Method for Optical Snow-Cover Mapping in Sparse Forest

A snow-cover mapping method for sparse forest by optical remote sensing is proposed. The method is based on linear sub-pixel reflectance modeling of the surface components snow, individual tree species, tree shadows and bare ground. Experiments are performed using a 100% snow-covered Landsat TM scene and aerial photos covering spruce, pine and birch forest in the Jotunheimen mountain area of South Norway. The results show that sub-pixel modeling of snow in sparse forest is possible, but effects of topography and direct and diffuse illumination, which influence the reflectance variability, should be accounted for to improve the results.