The present paper addresses the litho-dynamic and morpho-dynamic processes in the coastal zone of Babie Doły (KM 93.6–93.9), Poland. As a background, the history of coastal engineering measures in this area is described. The impact of post-war structures on the seashore is analysed on the basis of historical maps, supported by results of the sediment transport modelling. Shore regression is caused by the so-called downstream erosion behind the headland with remains of rock palisade structures. The possible consequences for the seashore resulting from the removal of the analysed revetment are discussed. The paper also presents recommendations to the relevant authorities for the future.

This paper treats the stability of two superposed gravitating streams rotating about the axis transverse to the horizontal magnetic field. The critical wave number for instability is found to be affected by rotation for propagation perpendicular to the axis about which the system rotates. The critical wave number for instability is not affected by rotation when waves propagate along the axis of rotation. The critical wave number is affected by both the magnetic field and the streaming velocity in both cases. Both the magnetic field and the rotation are stabilizing, while the streaming velocity is destabilizing.

The paper deals with the growing threat of erosion to the south Baltic coast, caused by the intensification of a wind-induced wave climate and sea level rise, which is expected to continue until 2100 as a result of climate change. In the analysis, a deep-water wave prognostic point is located about 13 km north-east of the Hel Peninsula, situated in the NW part of the Gulf of Gdańsk. The study comprises the analyses of wind velocity, storm surge, wave height, wave set-up and wave run-up. A significant predicted increase in wave heights during extreme storms, compared with the wave climate reconstructed for 1958–2001, combined with anticipated higher storm surges, is expected to result in a lower resilience of the sea shore to erosion and flooding. Although nourishment operations conducted along the open sea shore of the Hel Peninsula have proved efficient and successful, nourishment needs will have to be adequately recalculated in future to ensure sufficient protection of this coastal segment.