Influence of Upwelling on River Plume Development in the Coastal Zone of the North-Western Black Sea Shelf Based on Numerical Modelling

M. V. Tsyganova*, E. M. Lemeshko, Yu. N. Ryabtsev

Marine Hydrophysical Institute of RAS, Sevastopol, Russia

* e-mail: m.tsyganova@mhi-ras.ru

Abstract

In a south wind, coastal upwelling can be observed off the western coast of the Black Sea. In the same area, the hydrological structure of waters is strongly influenced by river runoff, which forms a river plume, and a southward longshore current. The paper studies the evolution of the plume on the northwest shelf of the Black Sea and its interaction with upwelling based on numerical modelling. The impact of upwelling development under the influence of the south wind on plume propagation was studied using a three-dimensional sigma-coordinate numerical model (POM-type) to calculate the circulation in the coastal zone taking into account the river runoff. The calculations were performed for a rectangular region for the cases of both uniform depth and typical water stratification of the northwestern shelf. The last case was sampled for May condition, when, on average, the Danube plume development is maximal. It is obtained that the joint dynamics of upwelling and river plume are closely related to the stratification of coastal waters. In the case of unstratified shelf waters, the thin plume layer enhances upwelling and downwelling on the inshore and offshore sides of the river plume, respectively. The results allowed studying the peculiarities of river water transformation during winds that cause the development of coastal upwelling. Estimates of the time of bottom water rise near the coast under the action of south winds with different wind speeds and shelf water stratification parameters retrieved from numerical modelling data can be used to develop regional upwelling indices based on satellite data on the sea surface temperature and wind speed.

Keywords

Black Sea, river plume, upwelling, numerical modelling, shelf, coastal zone, river runoff

Acknowledgments

The work was performed under state assignment on topic no. FNNN-2021-0005.

For citation

Tsyganova, M.V., Lemeshko, E.M., Ryabtsev, Yu.N., 2023. Influence of Upwelling on River Plume Development in the Coastal Zone of the North-Western Black Sea Shelf Based on Numerical Modelling. Ecological Safety of Coastal and Shelf Zones of Sea, (1), pp. 20–30. doi:10.29039/2413-5577-2023-1-20-30

DOI

10.29039/2413-5577-2023-1-20-30

References

  1. Horner-Devine, A.R., Hetland, R.D. and MacDonald, D.G., 2015. Mixing and Transport in Coastal River Plumes. Annual Review of Fluid Mechanics, 47, pp. 569–594. doi:10.1146/annurev-fluid-010313-141408
  2. Lemeshko, E.M. and Tsyganova, M.V., 2021. Investigation of Danube River Plume Formation and Propagation Based on Numerical Modeling. In: MSU, 2021. InterCarto. InterGIS. GI support of sustainable development of territories: Proceedings of the International conference. Moscow: MSU, Faculty of Geography, 2021. Vol. 27, part 3, pp. 32–41. doi:10.35595/2414-9179-2021-3-27-32-41 (in Russian).
  3. Kondratev, S.I., 2019. Three Typical Hydrological-Hydrochemical Situations near the Danube River Mouth Based on the Marine Hydrophysical Institute Research Expeditions in 1997-2013. Physical Oceanography, 26(4), pp. 326–340. doi:10.22449/1573-160X2019-4-326-340
  4. Bogdanova, A.K. and Korpachev, L.N., 1959. [Upsurge and Downsurge Circulation and its Role for the Hydrological Regime of the Black Sea]. Meteorologiya i Gidrologiya, (4), pp. 26–32 (in Russian).
  5. Borovskaya, R.V., Panov, B.N., Spyrydonova, E.O., Leksikova, L.A. and Kyrylova, M.V., 2005. Black Sea Near-Coastal Upwelling and Interannual Variability of Its Intensity. In: MHI, 2005. Ekologicheskaya Bezopasnost' Pribrezhnoy i Shel'fovoy Zon Morya [Ecological Safety of Coastal and Shelf Zones and Comprehensive Use of Shelf Resources]. Sevastopol: MHI. Iss. 12, pp. 42–48 (in Russian).
  6. Ginzburg, A.I., Kostianoy, A.G., Soloviev, D.M. and Stanichny, S.V., 2000. Coastal Upwelling in the North-West Black Sea. Earth Observation and Remote Sensing, 15(6), pp. 933–948.
  7. Stanichnaya, R.R. and Stanichny, S.V., 2021. Black Sea Upwellings. Sovremennye Problemy Distantsionnogo Zondirovaniya Zemli iz Kosmosa, 18(4), pp. 195–207. doi:10.21046/2070-7401-2021-18-4-195-207
  8. Zatsepin, A.G., Silvestrova, K.P., Kuklev, S.B., Piotoukh, V.B. and Podymov, O.I., 2016. Observations of a Cycle of Intense Coastal Upwelling and Downwelling at the Research Site of the Shirshov Institute of Oceanology in the Black Sea. Oceanology, 56(2), pp. 188–199. https://doi.org/10.1134/S0001437016020211
  9. Silvestrova, K.P., Myslenkov, S.A. and Repkov, D.S., 2022. Wind Upwelling Forecast for the Russian Black Sea Coast. Hydrometeorological Research and Forecasting, (1), pp. 89–107. https://doi.org/10.37162/2618-9631-2022-1-89-107
  10. Divinsky, B.V., Kuklev, S.B. and Zatsepin, A.G., 2017. Numerical Simulation of an Intensive Upwelling Event in the Northeastern Part of the Black Sea at the IO RAS hydrophysical testing site. Oceanology, 57(5), pp. 615–620. https://doi.org/10.1134/S0001437017040038
  11. Oguz, T., La Violette, P.E. and Unluata, U., 1992. The Upper Layer Circulation of the Black Sea: Its Variability as Inferred from Hydrographic and Satellite Observations. Journal of Geophysical Research: Oceans, 97(C8), pp. 12569–12584. doi:10.1029/92JC00812
  12. Mikhailova, E.N., Muzyleva, M.A., Polonskii, A.B., Soloviev, D.M. and Stanichny, S.V., 2009. [Spatial and Temporal Variability of Upwelling Characteristics in the Northwestern Part of the Black Sea and off the Crimean Coast in 2005–2008]. In: MHI, 2009. Monitoring Systems of Environment. Sevastopol: ECOSI-Gidrofizika. Issue 12, pp. 318–321 (in Russian).
  13. Osadchiev, A.A., 2021. River Plumes. Moscow: Scientific World, 285 p.
  14. Zavialov, P.O., Makkaveev, P.N., Konovalov, B.V., Osadchiev, A.A., Khlebopashev, P.V., Pelevin, V.V., Grabovskiy, A.B., Izhitskiy, A.S., Goncharenko, I.V., Soloviev, D.M. and Polukhin, A.A., 2014. Hydrophysical and Hydrochemical Characteristics of the Sea Areas Adjacent to the Estuaries of Small Rivers of the Russian Coast of the Black Sea. Oceanology, 54(3), pp. 265–280. doi:10.1134/S0001437014030151
  15. Kubryakov, A.A., Stanichny, S.V. and Zatsepin, A.G., 2018. Interannual Variability of Danube Waters Propagation in Summer Period of 1992–2015 and Its Influence on the Black Sea Ecosystem. Journal of Marine Systems, 179, pp. 10–30. https://doi.org/10.1016/j.jmarsys.2017.11.001
  16. Fong, D.A. and Geyer, W.R., 2002. The Alongshore Transport of Freshwater in a Surface-Trapped River Plume. Journal of Physical Oceanography, 32(3), pp. 957–972. https://doi.org/10.1175/1520-0485(2002)0320957:TATOFI2.0.CO;2
  17. Alory, G., Da-Allada, C.Y., Djakouré, S., Dadou, I., Jouanno, J. and Loemba, D.P., 2021. Coastal Upwelling Limitation by Onshore Geostrophic Flow in the Gulf of Guinea Around the Niger River Plume. Frontiers in Marine Science, 7, 607216. doi:10.3389/fmars.2020.607216
  18. Ivanov, V.A. and Fomin, V.V., 2010. Mathematical Modeling of Dynamical Processes in the Sea – Land Area. Kiev: Akademperiodika, 286 p.
  19. Tsyganova, M.V., Lemeshko, E.M. and Ryabcev, Yu.N., 2016. Modelling of Hydrofront Forming on the Danube Mouth Area. In: MHI, 2016. Ecological Safety of Coastal and Shelf Zones of Sea. Sevastopol: MHI. Iss. 3, pp. 26–31 (in Russian).
  20. Ivanov, V.A. and Belokopytov, V.N., 2013. Oceanography of the Black Sea. Sevastopol: ECOSI-Gidrofizika, 212 p.

Full text

English version (PDF)

Russian version (PDF)