The vegetation model SSiB was developed in the late 1980s. It is based on the SIB proposed by sellers et al. In 1986. The simplification is mainly aimed at the calculation of radiation transfer, aerodynamic drag coefficient and stomatal resistance coefficient in plants. The simplified SSiB has 1 layer of vegetation, 3 layers of soil and 8 forecast variables (moisture of 3 layers of soil, water content of vegetation surface, snow cover of soil surface and leaf surface temperature). Therefore, there are only two predictors: soil surface temperature and deep soil temperature. In the model, stomatal resistance coefficient, soil resistance coefficient, vegetation boundary layer resistance coefficient and two-layer aerodynamic resistance coefficient are used to control the dynamic, thermal and water exchange between the earth and the atmosphere.