Choosing an appropriate spatial resolution for remote sensing investigations

Choosing rationally the spatial resolution for remote sensing requires a formal relation between the size of support and some measure of the information content. The local variance in the image has been used to help choose an appropriate spatial resolution. Here we choose spatial resolutions to map continuous variation in properties, such as biomass, using the variogram. The experimental variogram can be separated into components of underlying spatially dependent variation and measurement error. The spatially dependent component can be deregularized to a punctual support, and then regularized to any spatial resolution. The regularized variogram summarizes the information attainable by imaging at that spatial resolution because information exists in the relations between observations only. The investigator can use it to select a combination of spatial resolution and method of analysis for a given investigation. Two examples demonstrate the method.