Department of Micrometeorology

With the data sets of the Waldstein-Weidenbrunnen site, different types of soil-vegetation-atmosphere transfer models were tested with different complexity and closure approaches. These are the STANDFLUX and SVAT-CN models in 1D and 3D resolution with a classical first-order closure according to the K-approach, the model FLAME with a 1,5-order transilient approach, and the ACASA model with a third-order closure. The presented comparison of model outputs and measured data was very satisfactory. Surprising was the good agreement, as well, of the first-order closure models inside the canopy, also in comparison to sap flow data. Only at nighttime, with a low coupling between the canopy and the atmosphere, did the higher-order closure model ACASA have advantages in comparison to the other models. This study has shown the nearly unrestricted applicability of the models like ACASA (1D) and SVAT-CN (3D) for tall vegetation and even low vegetation and tile approaches. And furthermore, the data sets of the Waldstein- Weidenbrunnen site are qualified for validation of different types of model.