Snow cover

Abstract

Satellites present an important component of the global snow observing system. Routine monitoring of the snow cover properties from space started in late 1960s. In this chapter, an overview is provided of techniques developed and used to identify snow cover in satellite images and to generate maps of snow cover distribution. The reviewed techniques include an interactive approach where snow maps are manually generated by human analysts through a visual examination of satellite imagery and automated algorithms that utilize satellite observations in multiple bands in the optical, infrared, and microwave spectral range. Satellite-based retrievals of the extent and the spatial distribution of snow cover are accurately and spatially detailed. Estimates of bulk snow pack properties such as the snow depth and the snow water equivalent are less reliable since they are strongly dependent on other snow pack features, particularly on the snow grain size and the snow pack stratification.