MEDAILLON: A German cooperative project to develop a high-resolution open meteorological dataset based on satellite and reanalysis data to support energy system analysis

The project MEDAILLON is a cooperation of Germany’s national meteorological service DWD (Deutscher Wetterdienst) with partners from the energy sector (Fraunhofer IEE, University of Kassel, menzio GmbH) and aims at the provision of an optimized meteorological dataset for energy applications. User involvement ensures that the data set is developed in line with user requirements. The focus of DWD’s contribution is based on two major elements: (1) Surface radiation can be derived from satellite data in high quality. The EUMETSAT Satellite Application Facility on Climate Monitoring develops long-term data records derived from observations of meteorological satellites. Their SARAH-3 dataset is derived from METEOSAT data and covers the period 1983 until today. (2) Wind information can be extracted from regional reanalyses. DWD started to develop regional reanalyses together with the Universities of Bonn and Cologne in 2011. The first version (COSMO-REA6) has already been used in a variety of energy-related activities. Currently, a reanalysis (ICON-DREAM: “ICON-Dual resolution Reanalysis for Emulators, Applications and Monitoring”) based on the current generation of the DWD’s NWP system (ICON) is produced. As the ICON-NWP-system applies an ensemble-based data assimilation scheme, the reanalysis is produced as an ensemble dataset and therefore allows to provide uncertainty information. ICON-DREAM currently covers the period from 2010 to today with a planned continuous extension to the current time, and a backward extension to the 1979 is in development. First quality assessments (Valmassoi et al., 2025) have shown that the observational biases and RSME are lower for ICON-DREAM than for COSMO-REA6 and ERA5. Within MEDAILLON, DWD aims at providing aggregated and optimized products for the energy sector derived from the ensemble reanalysis data. One additional priority is the evaluation of the relevant parameters, e.g. against independent observations from high measurement masts.

Valmassoi, A., J. D. Keller, R. Potthast, H. Anlauf, A. Cress, F. Kaspar, and A. Becker:  ICON-DREAM: the new dual resolution reanalysis from DWD. ICCARUS Book of Abstracts 2005. https://dx.doi.org/10.5676/DWD_pub/nwv/iccarus_2025