Das Projekt "Numerische und Beobachtungsuntersuchungen von Klimavariabilitaet und Prozessen in der Umgebung bergiger Gebiete (CLIMATE 2000)" wird vom Umweltbundesamt gefördert und von Universite Fribourg, Departement de Geographie durchgeführt. The main objective ot this project ist to verify climate model outputs, particularly in mountain regions in order to assess model capability in reproducing regional climate features in complex terrain (precipitation, blocking, surface parameterizations, etc.) The ultimate objective of the project is to improve global and regional model physics, in order to allow us to have more confidence in predictions of future climate change under enhanced greenhouse gas conditions. Leading Questions: The intercomparison between observations and high-resolution global and regional climate model results, to evaluate model performances in reproducing some of the spatial and temporal variability of climate at different scales. - The amelioration of specific model physical parametrization schemes to improve model performances in simulating present and future climate, with a particular emphasis on radiation, boundary-layer and surface processes. - Numerical and observational analyses of mechanisms controling temperature at high elevations. The causal processes will be investigated and related to the scale of the forcing mechanism; investigations will be made to determine whether these processes are also present in a warmer global climate as predicted for the 21st Century.^Le but de ce projet est de verifier les resultats de modeles de limat, particulierement dans les regions de montagnes, afin d'evaluer leur capacite a reproduire des phenomemes climatiques en milieu orographique complexe (precipitations, blocages, parametrisation de processus de surface, etc.). Le but final de l'etude est l'amelioration de la physique des modeles regionaux et globaux, permettant ainsi d'avoir plus de confiance dans les previsions du climat futur force par les gaz a effet de serre. (FRA)