Features of the Stokes Drift in the Northeastern Coastal Zone of the Black Sea from Modelling Results

B. V. Divinsky*, S. B. Kuklev, V. V. Ocherednik, O. N. Kukleva

Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia

* e-mail: divin@ocean.ru

Abstract

The Stokes drift generated by surface waves affects many physical processes occurring in the coastal zone of the sea, including heat and salt transport, as well as transport of pollutants. Taking into account the parameters of sea currents caused by the Stokes drift is important for a more correct description of the general hydrodynamic structure of coastal waters. Moreover, sea currents generated by surface waves make a significant contribution to the processes of accumulation and redistribution of pollutants in the coastal zone of the sea. The article presents the results of the study of the Stokes drift on the northeastern shelf of the Black Sea near Gelendzhik for the period from 2003 to 2022. Seasonal and interannual features of variability of Stokes current velocities and directions have been identified. It has been shown that from December to April, excluding February, the Stokes transport has comparable repeatability in directions towards the coast, away from the coast, and towards the northwest. In February, the main flow tends to the open sea. In May and June, the repeatability of currents towards the coastline increases significantly, with the contribution of currents to the southeast increasing at the beginning of summer. In July, the currents directed to the southeast and away from the coast become almost identical in terms of repeatability. From August to November, the proportion of currents directed away from the coast increases with a gradual decrease in the repeatability of currents towards the southeast. In multi-year terms, the flow directed away from the coast to the open sea prevails (repeatability of 34.3%). The same flow has the highest mean velocity (0.053 m/s). Repeatability of the long-shore currents directed towards the southeast and northwest is almost the same, but the currents towards the northwest are much more intense.

Keywords

wind waves, Stokes drift, coastal zone, spread of pollutants, anthropogenic pollution

Acknowledgments

The work was performed under agreement 075-15-2021-941 “Comprehensive studies of the ecological state of the waters of the coastal zone of the northeastern shelf of the Black Sea in the framework of participation in the international project DOORS” of the Ministry of Science and Higher Education of the Russian Federation.

For citation

Divinsky, B.V., Kuklev, S.B., Ocherednik, V.V. and Kukleva, O.N., 2024. Features of the Stokes Drift in the Northeastern Coastal Zone of the Black Sea from Modelling Results. Ecological Safety of Coastal and Shelf Zones of Sea, (1), pp. 6–19.

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