Das Projekt "Arktische Strahlungs- und Turbuelnzstudie" wird vom Umweltbundesamt gefördert und von Stiftung Alfred-Wegener-Institut für Polar- und Meeresforschung e.V. (AWI) durchgeführt. The warming of the lower atmosphere due to industrial activities is predicted by Global Circulation Models (GCM) to be most enhanced in the Arctic regions. The energy fluxes in the atmosphere and the radiative properties of clouds are of vital importance in an atmosphere of rising temperatures and especially in the Arctic are not yet represented by GCMs adequately, see results of the Atmospheric Model Intercomparison Project AMIP: WMO/TD 1992. The ARTIST programme aims to obtain an improved understanding of the radiative and thermodynamic interaction of Arctic clouds and sea-ice. The ARTIST programme will thoroughly study the energy fluxes in the atmosphere and at the surface of the polar ocean as well as cloud physical processes by field measurements atmospheric modelling and satellite remote sensing. An overall ARTIST objective is to derive optimized physical parameterizations for improved models of the Arctic Climate System. The programme ARTIST thus covers the Environment and Climate Workprogramme Basic processes in the climate system (Theme 1,Area 1,1,Topic 1,1,1, research tasks 2,3, and 4: and Area 1,2, Topic 1,2,1,2, research task 2,) Objective 1: ARTIST will assess the effects of clouds and of Arctic Haze on the radiative fluxes at the surface and in the atmospheric column for various states of the ocean surface. Objective 2: ARTIST studies the dynamics of the atmospheric boundary layer and especially the air-sea exchange of heat, momentum and vapour in Arctic regions by field experiments and process modelling.