Variability of the coastal currents, waves and wind surge along the shore of the South-Eastern Baltic (Kaliningrad Oblast, Russian Federation)

• Published in: Regional studies in marine science Vol. 57; p. 102762
• Main Authors: Chubarenko, Boris V., Sokolov, Andrei N., Dikii, Dmitrii I.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2023
• Subjects: Alongshore currents; Baltic sea; Coastal erosion; Coastal zone; Numerical modelling; Wave breaking; Alongshore currents; Coastal erosion; Numerical modelling; Coastal zone; Wave breaking; Baltic sea
• ISSN: 2352-4855; 2352-4855
• DOI: 10.1016/j.rsma.2022.102762

The coastline of the Kaliningrad Oblast is an area of the South-East Baltic, which continues from the Vistula Spit to the Curonian Spit via Sambia Peninsula. The coastline has been subject to severe erosion over the past years. The goal of the paper is to analyse whether the alongshore variations of the storm surge water level, field of waves and currents are the reason for the erosion alongshore variability. The numerical simulations were carried out using the quasi-stationary approach for the model wind. The offshore wave breaking distance and the non-linear dependence between wind surge and wind speed were estimated for four typical coastline sites. The alongshore velocity on most of the coastline was enough powerful to transport the fine, medium and coarse sands. West, northern-west and north winds were defined as the most dangerous for coastal erosion. The convergence and divergence of alongshore currents as well as the vortex zones were identified for each wind direction. The results were used to analyse the alongshore current velocity, wind surge, and significant wave height variability against the shore erosion characteristics. The hypothesis that the places of convergence and divergence of alongshore currents correspond to the accumulative and erosion zones was not confirmed with one exception on the western shore of the Sambia Peninsula. Three options were supposed to explain the absence of correlation between the monitoring results on coastal erosion and modelled hydrodynamic conditions: the studied shore has not had enough free sand to demonstrate the typical behaviour of dissipative shores; the erosion characteristics depend on the very local conditions which were not resolved by numerical model; the main erosion has happened at the short term event basis when waves reach the shore at the background of a general Baltic Sea high-water level and is not a result of the general alongshore distribution of waves, wave surge and current characteristics.