The European Storm Surge model (EFAS-COAST) has been developed for pan-European forecasting. It combines the continental-scale circulation model (SCHISM) and the continental-scale wave model (WWM III).
The magnitude of the storm surge depends on a number of factors including the size, track, speed and intensity of the storm system, the nearshore local bathymetry (water depth) and the shape of the coastline (Arns et al., 2015). The SCHISM model (Semi-implicit Cross-scale Hydroscience Integrated System Model) is based upon the original SELFE code (v3.1dc; Zhang and Baptista, 2008), with many enhancements and upgrades, including an extension to large-scale eddying regime and a seamless cross-scale capability from creek to ocean (Zhang et al., 2016). It is two-way coupled with the spectral wave model WWM III (Wind Wave Model III,) a wave spectral model developed by Hsu et al. (2005) and later updated by Roland et al. (2012).
EFAS-Coast accounts for the combined effect of, wind, atmospheric pressure gradients, tides and nearshore wave process. It provides storm surge levels, wave parameters (height, period, direction) and hazard level along European coastlines (spatial resolution: 10 km). The forecast, with a lead time of 3 days, is forced by atmospheric wind and pressure fields (ECMWF-IFS). Twice a day the forecast is refreshed.