Coastal erosion caused by the heavy storm surge of November 2004 in the southern Baltic Sea

The Swina Gate Sandbar (southern Baltic Sea) is affected by storm surges caused by passages of deep low-pressure systems over the Baltic Sea. The storm surge of 22-25 November 2004, with a maximum sea level of 1.35 m above mean sea level (MSL) as measured at the Swinoujscie gauging station, was one of the most severe storm events in 1993-2007. It produced changes in the coastal relief by inducing significant erosion of the dune shore in the western and eastern subsections of the sandbar area examined. Seawater flooded the beach and flowed over the low ridges, up to 3 m above MSL. As a result, all relief forms below the 3 m level were eroded, and the dunes retreated by an average of 2 to 6 m. The maximum amount of sediment that eroded away amounted to 22 m(3) per 1 m of coastline. This study showed that the magnitude of coastal erosion and retreat is dependent both on the height and the duration of the sea surge.