Copernicus European regional reanalysis

<p>The Copernicus European regional reanalysis (https://climate.copernicus.eu/regional-reanalysis-europe) was produced as part of the Copernicus Climate Change Service (C3S). The presentation will introduce the service and its main objectives as well as it will give an overview on available data. Data quality will be demonstrated by comparison with ERA5 and other gridded datasets.</p><p>The Copernicus European Regional ReAnalysis (CERRA) is produced with a setup of the HARMONIE-ALADIN model system including a 3D-Var data assimilation scheme for upper air observations and an OI-scheme for surface observations. The model domain covers entire Europe at a horizontal resolution of 5.5 km. The system provides eight analyses per day – at 0 UTC, 3 UTC, 6 UTC, … and 21 UTC. Between the analyses, data are available with hourly resolution from the forecast model. More than fifty parameters are available on various level types including surface parameters and data up to 1 hPa. Data are available for the period September 1984 – June 2021 through Copernicus Climate Data Store (CDS).</p><p>In addition to CERRA, the service produced a reanalysis with an ensemble of data assimilation (EDA) system, called CERRA-EDA. CERRA-EDA consists of 10 members and is produced with a horizontal resolution of 11 km. Uncertainty information from the ensemble system is used as a flow depending part of the B-matrix for CERRA. Another product of the service is CERRA-Land. CERRA-Land provides daily precipitation analyses as well as parameters from the surface/soil model SURFEX, which is driven with CERRA data.</p><p>In the presentation, the production chain will be illustrated and the availability of data will be clarified. The focus will be on CERRA. The quality of the regional reanalysis will be demonstrated in comparison to the global reanalysis ERA5. For instance, investigations of the winter storm Gudrun (January 2005, southern Sweden) will be presented. </p>