A data set on land surface/ atmosphere interaction processes over a heterogeneous land surfaces at the meso-γ scale has been collected during the LITFASS-2003 experiment which was embedded in the operational measurement program of the MOL. A hirarchy of instruments and methods was used to derive the fluxes of the energy and water vapor from the local to the regional scale including eddy-covariance measurements. The data collected during LITFASS-2003 are used either as boundary conditions and forcing data from different kinds of numerical models or as a verification data set within the EVA_GRIPS project. The EVA_GRIPS project will contribute to improve the surfaces processes parameterisation schemes in NWP and climate models.