Morphologic and hydrodynamic conditions of Hel Peninsula's abrasion in the Ku nica region (southern Baltic)

The purpose of the presented paper is the identification and assessment of causes of intensive abrasion in the open coastline of the Hel Peninsula and the effect of countermeasures. Numerical modeling of nearshore hydrodynamics, topographic analysis and field measurements were carried out. The Baltic Sea hydrodynamic model, a model of wave-induced nearshore circulation and the wave model SWAN were employed. 3D hydrodynamic modeling resulted in the become visible that fields of shear bottom stresses as well as bottom currents depended on atmospheric forcing and depth. A correlation between bottom stresses and topography was obtained. The results of modeling of the nearshore hydrodynamics demonstrated a dominant role for alongshore sediment transport. The magnitude of both cross-and alongshore wave-induced currents strongly depended on wave height gradient, which was significantly greater in storm periods. During storms, sediment transport occurs also in the cross-shore direction.