The characteristics of the snow cover (extension, size and shape of the grains, surface roughness and thickness) vary naturally in cold regions over the seasons. Unexpected and sudden changes of the seasonal snow cover are compromising, in the recent years, the fragile equilibrium of polar and mountainous areas. Monitoring of these surfaces is therefore the key for climatic-environmental studies and the availability of information about the snow cover can significantly help the characterization of environmental changes in time and space. Different tools are based on the optical behavior of the snow and each approach can describe a different feature of the snowed surface. The interaction between the light and the surface is controlled, in the visible and near infrared wavelengths, by the presence of impurities, by the size and shape of the grains and by the liquid water content. Exploring and investigating the relationship between the reflected light and the snow micro-physics, we can describe the extension of the snow cover, the beginning of the melt season and to study its surface microphysical properties.