Abstract: Images of a selected geographic region are obtained using remote sensing apparatus and are processed to determine characteristic spectral reflectance patterns associated with different ground covers and soil types in the region. The image processing means compares the spectral reflectance patterns to image pixel values in order to classify each pixel in a ground cover or soil type class, the corresponding spectral reflectance pattern for which matches the pixel value. In a preferred embodiment of the invention, Geographic Information System (GIS) software is utilized to combine a remotely sensed image providing ground cover classifications for a geographic region with a remotely sensed image providing soil type classifications for the same region in order to generate a rainfall loss function.