The European Flood Awareness System (EFAS) version 5.0 is scheduled for operational release on the EFAS-IS on 20 September 2023.
EFAS v5.0 introduces several major changes to the system, including:
A higher spatial resolution. EFAS v5.0 has a 1 arcmin / 0.0167 degrees resolution (~1.4km), as opposed to the 5-km resolution of all the previous EFAS versions.
A different projection system, now based on EPSG:4326 instead of ETRS89 Lambert Azimuthal Equal Area Coordinate Reference System (ETRS-LAEA) for previous versions.
A larger modelling domain whose extension has been enlarged to match the river catchments.
An entirely new set of 0.0167 degrees resolution input maps produced using the most recent research findings, remote sensing, and in-situ datasets.
Major improvements to the open-source hydrological model LISFLOOD.
A new calibration at 1903 in-situ gauging stations. Furthermore, a parameter regionalisation was performed to estimate the parameters of catchments for which in situ discharge observations were not available.
New return period thresholds and snow water/soil moisture anomaly maps based on a climatology from 1992-2022. The EFAS v5 river discharge climatology is available at the C3S Climate Data Store.
Updated EFAS Seasonal and Sub-seasonal forecasts using the newly calibrated, higher resolution hydrological model.
New flood hazard maps generated using LISFLOOD-FP at 90m resolution.
This upgrade of EFAS has large impacts on the EFAS modelling results.
For more information about the latest operational EFAS release and previous versions of EFAS, we refer users to the dedicated wiki pages. Data will be accessible following the operational release and information will be provided through our dedicated wiki page on data access.
As always, we invite your feedback on the pre-release of EFASv5.0. Questions and feedback can be addressed to the CEMS Floods team via the EFAS contact form.