Snow Cover Model for Global Climatic Simulations

摘要

A layered one dimensional model of a snow cover, which combines a relativelyaccurate model physics and a short computer time, is presented. The model simulates the important internal processes of temperature and water vapor diffusion, melting, and freezing, extinction of short wave radiation, and liquid water retention. It is based on the mass and energy balances and can be utilized for both temporal and permanent snow covers. In order to keep the possibility of using the model on a global scale, no local parameterizations are employed. An efficient numerical scheme makes the model suitable for long term climatic studies. Integrations for Potsdam (East Germany), 52 deg north, 13 deg east, with standard synoptic measurements over a period of six winters demonstrate a very good correspondence between the observed and computed values. The remaining problem is the choice of a satisfactory criterion for the distinction between snow and rain which strongly influences the situation results of snow depth and water equivalent.