Morphodynamics of the Bakalskaya Spit of the Black Sea

Abstract

Studies of shape dynamics of the Bakalskaya Spit based on observation and numerical simulation are carries out. The Bakalskaya Spit is a dynamically active sand formation on the north-west coast of the Crimea Peninsula. Field observations and satellite image analyses showed that the erosion of spit west coast, eastward displacement of spit distal part and separation of distal part from the spit main part are the most significant processes. After the autumn storms in 2010 the isthmus between the distal part of spit and its main part was eroded and had not recovered till now. So the distal part of the Bakalskaya Spit turned into island. Dynamic of sediments depends on wind wave parameters and sea level oscillations. Effect of changing of wind wave direction and storm surge height on erosion and deposition processes in the Bakalskaya Spit region of the Black Sea is studied by using of XBeach numerical model. Dependencies of location and space dimension of erosion and deposition areas of sediments on characteristics of waves and surges are obtained. It is found that the most intensive erosion of spit isthmus occurs in case of wave running from the west in comparison of cases of wave running from the south-west and north-west if there are no surges. Presence of surges may results in increasing or decreasing of erosion process intensiveness depending on wave direction.