Climatic Variability of the Black Sea Thermohaline Characteristics (1950–2023)

V. N. Belokopytov, E. V. Zhuk

Marine Hydrophysical Institute of RAS, Sevastopol, Russian Federation

e-mail: v.belokopytov@gmail.com

Abstract

Purpose. The purposes of the study are to create a new climatic array of thermohaline fields in the Black Sea, to estimate (on its basis) climate changes during the last decades and to compare them with the global climatic tendencies in the World Ocean.

Methods and Results. A new climatic array of thermohaline fields in the Black Sea (MHI-2024) with a spatial grid of 1/6° × 1/4° has been created in Marine Hydrophysical Institute of RAS based on statistical processing of more than 123 thousand hydrological stations for 1950‒2023 using optimal interpolation methods. The climate atlas and the digital array are the open access products and can be used in climate studies, mathematical modeling, as well as in solving various applied problems. The deviations of initial data and averaged values from the climatic fields in the MHI-2024 array have constituted a basis for calculating the parameters of temporal variability at different scales and forming the time series of average monthly/annual anomalies. It is revealed that after 2015, sea warming in the 0–100 m layer steadily exceeded the natural background of interannual variability, at that its maximum increase fell on the summer-autumn seasons. Since about 2010–2012, a sharp salinity growth has been observed which does not yet surpass the standard deviation (SD) of interannual variability. The highest salinity increase in the course of a seasonal cycle occurs in spring and autumn when the water balance in the basin is at its maximum.

Conclusions. The Black Sea is related to the areas with the increased rates of climate changes, such as tropical parts of the World Ocean. The high temperature rise in the Black Sea over the past 40 years is the second in intensity as compared to that of the Arctic seas. Salinity growth in the Black Sea over a 70-year period is close to that in the areas of subtropical anticyclonic gyres where sharp salinification, atypical for the ocean, has been observed for the past 20 years. The current warm and saline stage of the Black Sea hydrologic state is similar to the conditions in 1960–1970, but with greater oscillation amplitude. The obtained results have a wide range of applications including formation of general ideas about the carbon cycle mechanisms in the Azov-Black Sea basin.

Keywords

Black Sea, thermohaline structure, climatic array, climate change, global warming, salinity, water temperature

Acknowledgements

The study was carried out within the framework of state assignments of FSBSI FRC MHI on themes FNNN-2024-0014 and FNNN-2023-0001.

Original russian text

Original Russian Text © V. N. Belokopytov, E. V. Zhuk, 2024, published in MORSKOY GIDROFIZICHESKIY ZHURNAL, Vol. 40, Iss. 6, pp. 838–852 (2024)

For citation

Belokopytov, V.N. and Zhuk, E.V., 2024. Climatic Variability of the Black Sea Thermohaline Characteristics (1950–2023). Physical Oceanography, 31(6), pp. 788-801.

References

  1. Gertman, I.F., 1991. [Thermohaline Structure of the Black Sea]. In: A. I. Simonov and E. N. Altman, eds., 1991. Hydrometeorology and Hydrochemistry of Seas in the USSR. Vol. 4. Black Sea. Issue 1. Hydrometeorological Conditions. St. Petersburg: Gidrometeoizdat, pp. 146-195 (in Russian).
  2. Locarnini, R.A., Mishonov, A.V., Baranova, O.K., Boyer, T.P., Zweng, M.M., Garcia, H.E., Reagan, J.R., Seidov, D., Weathers, K.W. [et al.], 2019. World Ocean Atlas 2018. Volume 1: Temperature. Silver Spring, MD, USA: NOAA Atlas NESDIS, 52 p.
  3. Zweng, M.M., Reagan, J.R., Seidov, D., Boyer, T.P., Locarnini, R.A., Garcia, H.E., Mishonov, A.V., Baranova, O.K., Weathers, K.W. [et al.], 2019. World Ocean Atlas 2018. Volume 2: Salinity. Silver Spring, MD, USA: NOAA Atlas NESDIS, 50 p.
  4. Suvorov, A.M., Palmer, D.R., Khaliulin, A.K., Godin, E.A. and Belokopytov, V.N., 2003. Digital Atlas and Evaluation of the Influence of Inter-Annual Variability on Climate Analyses. In: Oceans 2003. Celebrating the Past… Teaming Toward the Future. San Diego, CA, USA: IEEE. Vol. 2, pp. 990-995. https://doi.org/10.1109/OCEANS.2003.178468
  5. Polonsky, A.B., Shokurova, I.G. and Belokopytov, V.N., 2013. Decadal Variability of Temperature and Salinity in the Black Sea. Morskoy Gidrofizicheskiy Zhurnal, (6), pp. 27-41 (in Russian).
  6. Miladinova, S., Stips, A., Garcia-Gorriz, E. and Macias Moy, D., 2017. Black Sea Thermohaline Properties: Long-Term Trends and Variations. Journal of Geophysical Research: Oceans, 122(7), pp. 5624-5644. https://doi.org/10.1002/2016JC012644
  7. Polonsky, A.B. and Serebrennikov, A.N., 2023. Changes in the Nature of Temperature Anomalies of the Black Sea Surface during the Warming Period of the Late 20th – Early 21st Centuries. Issledovanie Zemli iz Kosmosa, (6), pp. 118-132. https://doi.org/10.31857/S0205961423060064 (in Russian).
  8. Belokopytov, V.N., 2011. Interannual Variations of the Renewal of Waters of the Cold Intermediate Layer in the Black Sea for the Last Decades. Physical Oceanography, 20(5), pp. 347-355. https://doi.org/10.1007/s11110-011-9090-x
  9. Capet, A., Troupin, C., Carstensen, J., Grégoire, M. and Beckers, J.-M., 2014. Untangling Spatial and Temporal Trends in the Variability of the Black Sea Cold Intermediate Layer and Mixed Layer Depth Using the DIVA Detrending Procedure. Ocean Dynamics, 64(3), pp. 315-324. https://doi.org/10.1007/s10236-013-0683-4
  10. Miladinova-Marinova, S., Stips, A., Garcia Gorris, E. and Macias Moy, D., 2018. Formation and Changes of the Black Sea Cold Intermediate Layer. Progress in Oceanography, 167, pp. 11-23. https://doi.org/10.1016/j.pocean.2018.07.002
  11. Stanev, E.V., Peneva, E. and Chtirkova, B., 2019. Climate Change and Regional Ocean Water Mass Disappearance: Case of the Black Sea. Journal of Geophysical Research: Oceans, 124(7), pp. 4803-4819. https://doi.org/10.1029/2019JC015076
  12. Polonskii, A.B. and Novikova, A.M., 2020. Interdecadal Variability of the Black Sea Cold Intermediate Layer and Its Causes. Russian Meteorology and Hydrology, 45(10), pp. 694-700. https://doi.org/10.3103/S1068373920100039
  13. Cressman, G.P., 1959. An Operational Objective Analysis System. Monthly Weather Review, 87(10), pp. 367-374. https://doi.org/10.1175/1520-0493(1959)0870367:AOOAS2.0.CO;2
  14. Barnes, S.L., 1964. A Technique for Maximizing Details in Numerical Weather Map Analysis. Journal of Applied Meteorology and Climatology, 3(4), pp. 396-409. https://doi.org/10.1175/1520-0450(1964)003%3C0396:ATFMDI%3E2.0.CO;2
  15. Rixen, M., Beckers, J.-M., Brankart, J.-M. and Brasseur, P., 2000. A Numerically Efficient Data Analysis Method with Error Map Generation. Ocean Modelling, 2(1-2), pp. 45-60. https://doi.org/10.1016/S1463-5003(00)00009-316
  16. Barth, A., Beckers, J.-M., Troupin, C., Alvera-Azcàrate, A. and Vandenbulcke, L., 2014. DIVAnd-1.0: n-Dimensional Variational Data Analysis for Ocean Observations. Geoscientific Model Development, 7(1), pp. 225-241. https://doi.org/10.5194/gmd-7-225-2014
  17. Belokopytov, V.N., 2018. Retrospective Analysis of the Black Sea Thermohaline Fields on the Basis of Empirical Orthogonal Functions. Physical Oceanography, 25(5), pp. 380-389. https://doi.org/10.22449/1573-160X-2018-5-380-389
  18. Bretherton, F.P., Davis, R.E. and Fandry, C.B., 1976. A Technique for Objective Analysis and Design of Oceanographic Experiments Applied to MODE-73. Deep Sea Research and Oceanographic Abstracts, 23(7), pp. 559-582. https://doi.org/10.1016/0011-7471(76)90001-2
  19. Grigor’ev, A.V., Ivanov, V.A. and Kapustina, N.A., 1996. Correlation Structure of the Black Sea Thermohaline Fields in the Summer Season. Oceanology, 36(3), pp. 334-339.
  20. Polonskii, A.B. and Shokurova, I.G., 2008. Statistical Structure of the Large-Scale Fields of Temperature and Salinity in the Black Sea. Physical Oceanography, 18(1), pp. 38-51. https://doi.org/10.1007/s11110-008-9008-4
  21. Ivanov, V.A. and Belokopytov, V.N., 2013. Oceanography of the Black Sea. Sevastopol: ECOSI-Gidrofizika, 212 p.

Download the article (PDF)