Challenges in Studying and Modeling Heat and Moisture Exchange in Soil–Vegetation/Snow Cover–Surface Air Layer Systems

The current state of the art in the investigation and modeling of soil–vegetation/snow cover–surface air layer system (SVAS) is briefly reviewed. This system plays a decisive role in the formation of heat and moisture exchange between the land surface and atmosphere. The SWAP model, developed by the authors of this paper, is used to illustrate the potentialities of SVAS models in reproducing the dynamics of components of water and heat balances of the land surface under different natural conditions and at different spatial and temporal scales. The challenges and perspectives of further development of SVAS models are analyzed.