The Global-to-Regional ICON Digital Twin

The Global-to-Regional ICON (GLORI) Digital Twin is a project made possible by the tri-lateral cooperation between Germany, Italy and Switzerland. The project is fostered by the ICON cooperation and by the long-lasting collaboration in the COSMO Consortium and in the CLM Community. The partnership includes national weather and climate services as well as research institutes, which bring together a broad and transdisciplinary expertise. Project partners are the Deutscher Wetterdienst (DWD), the Forschungszentrum Jülich (FZJ) and the Karlsruher Institut für Technologie (KIT) in Germany, the Centro euro-Mediterraneo sui Cambiamenti Climatici (CMCC), the Agenzia per la meteorologia e climatologia ItaliaMeteo (IM), the HydroMeteoClimate Service of Arpae Emilia-Romagna (Arpae-SIMC) and the Servizio meteorologico dell'Aeronautica Militare (MeteoAM) in Italy and the Swiss Federal Office for Meteorology and Climatology (MeteoSwiss) in Switzerland. GLORI is a configurable on-demand global-to-regional short-range high resolution digital twin based on the prediction capability of ICON. The twin is fit to run on heterogeneous GPU-CPU architecture at high resolution. It provides short-range global storm-resolving km-scale (~3 km horizontal) predictions using hybrid variational ensemble data assimilation. GLORI offers on-demand high resolution (~ 500m -1 km horizontal) predictions for the selected regions, like GLORI-Alps, the twin on the Alpine region. It includes uncertainty estimation through ensemble forecast for global and regional. Model parametrisations are developed to take into account higher-resolution and the complexity of the land-surface interface. It is possible to carry out on-demand predictions of selected atmospheric composition elements such as mineral dust for energy applications and pollen for health applications. The digital twin also includes interfaces to application layers in the hydrological area. The skill of the twin in forecasting precipitation at high-resolution will be also demonstrated on catchments by using a hydrological model as user-oriented verification tool.