Inclusion of soil freezing in the Land Surface Process Model (LSPM)

The lack of parameterization of soil frozen water in land-surface models may cause considerable errors in soil temperature and moisture as well as surface fluxes and runoff estimation. In this work, LSPM (Land Surface Process Model) was updated to include the water phase changes into the soil. Two parameterizations were implemented into the model and both were tested with and without coupling between soil temperature and moisture equations. Latent heat flux and thus soil temperature simulations improved with both parameterizations regardless of coupling or not, while soil water content was better reproduced when the temperature-moisture coupling was not activated. Soil water freezing/thawing parameterization should be further investigated to refine land surface model outputs in order to their practical applications or their use for research purposes.