Das Projekt "Wolkenarchiv-Nutzerservice" wird vom Umweltbundesamt gefördert und von Max-Planck-Institut für Meteorologie durchgeführt. General Information: The fundamental aim of the Cloud Archive User Service (CLAUS) project is to provide climate modellers with easy access to an archive of satellite based doud data. This aim can be sub-divided into three separate, measurable objectives: Objective Data set provision. It is proposed to prepare an archive of integrated satellite images based upon data from the International Satellite Cloud Climatology Project (ISCCP) and covering the period 1983 - present. In response to customer requirements these data will be produced on a regular 0.50 grid at 3-hourly intervals. The data processing method will be based on a technically proven method developed using single year of data. Objective 2Data Access. The data, and descriptions of the integration methods employed, would be made freely available over the network using the CEO European Wide Service Exchange (EWSE). Objective 3 Operational Testing: The archived data will be tested by the participating climate research groups in an operational environment over an extended period. Following an infial testing phase, modifications may be made in consultation with the users. The customers for CLAUS are global climate modellers and climate researchers who need to compare observed data (as provided by CLAUS) with their own model outputs. Such comparisons would allow the models to be improved and be of enormous benefit to the climate modelling community. The development of General Circulation Models (GCMs) able to reproduce climate variables on various spatial and temporal scales, coupled with increases in computing power, has ied to greatly increased understanding of the world's climate. However, there are very real difficulties in validating the models; the Intergovernmental Panel on Climate Change (IPCC) has identified the provision of observational data for GCMs as oiling a critical factor in their validation and Improvement (IPCC, 1992). Further, the IPCC identified inadequate understanding of clouds as being among the key uncertainties in climate understanding (IPCC, 1992). These concerns were re-emphasised in the recent 1996 report tlPCC, 1996). This project is customer driven. The project will be co-ordinated by the UK NERC Environmental Systems Science Centre (ESSC), who are an interdisciplinary group with a strong background in linking models with observations. Five of the six major climate modelling centres in Europe are active partners: Centre National de Recherches Meteorologie (CNRM), France; laboratoire de Meteorologie Dynamique (LMD), France; Max-Pianck- Institut fur Meteorologie (MPI), Germany; UK Universities Global Atmospheric Modelling Programme (UGAMP). UK; European Centre for Medium-Range Weather Forecasts (ECMWF), European; and the other major climate modelling centre, the UK Hadley Centre, will be collaborating closely. ... Prime Contractor: University of Reading, Environmental Systems Science Centre; Reading; United Kingdom.