COSMO-CLM²: a new version of the COSMO-CLM model coupled to the Community Land Model

Radiation fluxes as well as turbulent fluxes at the surface are found to be more realistically represented in COSMOCLM 2. This subsequently leads to improvements of several aspects of the simulated climate (cloud cover, surface temperature and precipitation). We show that a better partitioning of turbulent fluxes is the central factor allowing for the better performances of COSMO-CLM² over COSMO-CLM.

Despite these improvements, some model deficiencies still remain, most notably a substantial underestimation of surface net shortwave radiation. Overall, these results highlight the importance of land surface processes in shaping the European climate and the benefit of using an advanced land surface model for regional climate simulations.