A distributed model of runoff generation in the permafrost regions

A physically based distributed model of snowmelt and rainfall runoff generation in the permafrost regions has been developed. The model describes snow cover formation and snowmelt, thawing of the ground, evaporation, basin water storage dynamics, overland, subsurface and channel flow. An important feature of the model is taking into account influence of the depth of thawed ground on water input, water storage and redistribution of water input between surface and subsurface flow. The choice of the structure of the model is based on the analysis of the long-term observations of the runoff generation processes at the Kolyma water balance station and is orientated to the available standard hydrometeorological information in the cold regions. A case study of the proposed model has been performed for the Upper Kolyma River basin (the catchment area is 99,400 km2).