Màster de Meteorologia, Facultat de Física, Universitat de Barcelona, Curs: 2014-2015, Tutores: Maria Rosa Soler Duffour, Mireia Udina SistachDifferent types of land use have different physical properties which can change the radiation and energy balances and hence vertical fluxes of moisture, heat and momentum which also lead to changes in temperature and moisture felds near the surface. Simulating atmospheric ows over complex terrain is still a challenge, because the grid spacing in models must be reduced to better represent the topography, and increasing the resolution below 1 km implies to improve the land use land database at the same resolution. For this reason, in this work we adapted Corine Land Cover (CLC) land use database to the Weather Research and Forecasting (WRF) model using a reclassify methodology. We compare changes in the most in uenced meteorological variables and we test them in a zone of complex topography. Likewise, the simulated values for the adapted CLC and the default dataset, U.S. Geological Survey (USGS), have been compared with observational data in the Pyrenees valley of 'La Cerdanya' during a 9 day period in the 2013 summer. Physical interpretation of the results have been done using parameters such as thermal inertia or soil moisture availability showing the importance of land use and topography resolution in mesoscale meteorological modelling. In addition, statistical validation has been done to test the performance of the model with the new land use database. In general, results show that using CLC we achieved a better model performance in all the different simulations.