Recent updates of the Coastal Early Warning System of the Emilia-Romagna Region (Italy): oceanographic forecasts at the local scale

The coastal areas of Emilia-Romagna (Northern Italy) are characterised by different environments, including sandy beaches and the transitional areas of the Po Delta. The low-lying sandy beaches render the local coastlines highly vulnerable to extreme meteo-marine events, which can have serious consequences such as marine ingression, coastal erosion and flooding. 

The Regional Agency for Prevention, Environment and Energy of Emilia-Romagna (Arpae) manages an Operational Early Warning System for Coastal Risks (EWS) that provides daily forecasts, integrated with a Regional Observing Network. 

The EWS consists of different implementations of a meteorological model (COSMO), a wave model (SWAN-MEDITARE), an oceanographic model (Adriac, based on COAWST) and a morphodynamics model (XBeach). Adriac oceanographic forecasts are carried out on a regular grid with a fixed resolution (1 km). Structured grids, however, struggle to accurately resolve short scale physical processes and complex bathymetries, especially given the complexity of the regional coastline.. For this reason, a very high resolution hydrodynamic model for the Po Delta and the Emilia-Romagna coast, extending inland up to the Pontelagoscuro station (river flow measurements), was developed. The model (shyfER) is based on the SHYFEM code that solves the hydrodynamic equations on unstructured meshes. It provides daily forecasts (+72 hours) of total water level, salinity, temperature and currents.

As salt intrusion in the Po Delta is an important phenomenon that has increased in frequency and intensity in recent years, the model performance in terms of salt wedge representation is currently being evaluated. Furthermore, tests were conducted in terms of microbiological dispersion simulations by coupling the model with BFM (Biogeochemical Fluxes Model) in a 0-dimensional setting.

Finally, it is crucial not to overlook the significance of observations, as they enable accurate calibration and validation of models. Thanks to European funding, Arpae has been able to expand its marine-coastal observation network, which currently consists of three tide gauges (at Porto Garibaldi, Cattolica and Cervia), a wave buoy with a current-meter (at Cesenatico) and various multiparametric stations. In addition, a regional monitoring network of eight webcams (camERa) has been installed along the regional littoral allowing continuous monitoring of the coastal areas.

Arpae-SIMC is currently involved in several projects to maintain and update the system, including the DIRECTED project (Horizon 2020), which focuses on the "power" of the Early Warning Systems. Together with the Civil Protection of the Emilia-Romagna Region (ARSTPC-ER) Arpae leads the Real-World Lab in Emilia-Romagna.