Modeling of Processes of Snow Cover Formation and Snowmelt

The chapter contains the general information on snow properties and main processes which occur in snow pack during cold period and during snowmelt. The models of hydrothermal processes and heat and moisture transfer in the dry and melting snow pack are described. The methods of calculation of snowmelt rate based on the energy budget of snow pack have been reviewed. To interpolate the spatial distributions of snow characteristics and to take into account the variation of statistic parameters of snow characteristics inside of areas of different sizes, the snow covers are considered as random fields. Variograms and correlograms of these fields constructed for a number of the river basins of various sizes have shown that for these fields in many cases can be accepted the hypotheses of homogeneity and isotropy which are allowed to use for snow interpolation the methods of kriging or optimal interpolation. The conditions of statistical selfsimilarity of random fields are presented and estimation of fractal dimensions of the snow depth and the snow water equivalent fields of different scales has been made.