Variance of Short-Period Sea Level Oscillations in the Black Sea: Seasonal and Interannual Variations

I. P. Medvedev

Shirshov Institute of Oceanology of RAS, Moscow, Russian Federation

e-mail: patamates@gmail.com

Abstract

Purpose. The study is aimed at investigating the peculiarities of seasonal and interannual variations of the variance of short-period sea level oscillations in the Black Sea.

Methods and Results. The peculiarities of changes in the variance (energy) of synoptic (2–30 days) and mesoscale (2 h – 2 days) sea level oscillations in the Black Sea were studied based on the analyses of long-term sea level observation series. The results of spectral analysis made it possible to find out that on the eastern coast of the Black Sea, the spectral density of sea level oscillations increases from summer to winter and decreases from winter to summer within the frequency range of 0.1–0.8 cycles/day. As for the northwestern and Crimean coasts, the spectral density is practically the same in autumn and winter, further it decreases in spring and summer. The interannual changes of the variance of synoptic oscillations on the eastern sea coast are characterized by a negative trend achieving – 0.25 cm2/year in Batumi and – 0.41 cm2/year in Poti. The variance of mesoscale sea level oscillations has negative trends with the rates from – 0.21…– 0.24 cm2/year in Odessa and Nikolaev to – 0.13 cm2/year in Gelendzhik.

Conclusions. The variance of short-period sea level oscillations in the Black Sea increases from summer to winter and decreases from winter to summer that is related to the intensification of cyclonic activity in the atmosphere during autumn and winter. A local seasonal decrease in the variance of sea level oscillations is observed in the estuaries of large rivers in winter due to the developed ice cover preventing the formation of wind surges and seiches. At that, the higher the oscillation frequency, the stronger the ice cover influence.

Keywords

sea level oscillations, Black Sea, synoptic variability, spectrum, variance

Acknowledgements

The research was carried out within the framework of a state assignment of IO RAS (theme No. FMWE-2024-0018).

Original russian text

Original Russian Text © I. P. Medvedev, 2024, published in MORSKOY GIDROFIZICHESKIY ZHURNAL, Vol. 40, Iss. 1, pp. 65–77 (2024)

For citation

Medvedev, I.P., 2024. Variance of Short-Period Sea Level Oscillations in the Black Sea: Seasonal and Interannual Variations. Physical Oceanography, 31(1), pp. 59-70.

References

  1. Wunsch, C., 1972. Bermuda Sea Level in Relation to Tides, Weather, and Baroclinic Fluctuations. Reviews of Geophysics, 10(1), pp. 1-49. doi:10.1029/RG010i001p00001
  2. Medvedev, I.P., Rabinovich, A.B. and Kulikov, E.A., 2016. Tides in Three Enclosed Basins: the Baltic, Black, and Caspian Seas. Frontiers in Marine Science, 3, 46. doi:10.3389/fmars.2016.00046
  3. Medvedev, I.P., 2018. Tides in the Black Sea: Observations and Numerical Modelling. Pure and Applied Geophysics, 175(6), pp. 1951-1969. doi:10.1007/s00024-018-1878-x
  4. Ferrarin, C., Bellafiore, D., Sannino, G., Bajo, M. and Umgiesser, G., 2018. Tidal Dynamics in the Inter-Connected Mediterranean, Marmara, Black and Azov Seas. Progress in Oceanography, 161, pp. 102-115. doi:10.1016/j.pocean.2018.02.006
  5. Medvedev, I.P., 2018. Analysis of Variance of the Black Sea Level Oscillations in a Wide Range of Frequencies. Physical Oceanography, 25(6), pp. 448-458. doi:10.22449/1573-160X-2018-6- 448-458
  6. Medvedev, I.P., 2015. Formation of the Baltic Sea Level Spectrum. Doklady Earth Sciences, 463(1), pp. 760-764. doi:10.1134/S1028334X1507020X
  7. Ivanov, V.A. and Yankovskyii, A.E., 1992. [Long-Wave Motion in the Black Sea]. Kiev: Naukova Dumka, 110 p. (in Russian).
  8. Ivanov, V.A. and Belokopytov, V.N., 2013. Oceanography of Black Sea. Sevastopol: ECOSI- Gidrofizika, 210 p.
  9. Medvedev, I.P., 2022. Numerical Modeling of Meteorological Sea Level Oscillations in the Black Sea. Oceanology, 62(4), pp. 471-481. doi:10.1134/S0001437022040087
  10. Medvedev, I.P. and Kulikov, E.A., 2016. Spectrum of Mesoscale Sea Level Oscillations in the Northern Black Sea: Tides, Seiches, and Inertial Oscillations. Oceanology, 56(1), pp. 6-13. doi:10.1134/S0001437016010094
  11. Ivanov, V.A. and Yastreb, V.P., 1989. Fluctuations of the Black Sea Level. Water Resources, 16(2), pp. 173-179.
  12. Stanev, E.V., Grashorn, S. and Zhang, Y.J., 2017. Cascading Ocean Basins: Numerical Simulations of the Circulation and Interbasin Exchange in the Azov-Black-Marmara- Mediterranean Seas System. Ocean Dynamics, 67(8), pp. 1003-1025. doi:10.1007/s10236-017- 1071-2
  13. Aydın, M. and Beşiktepe, Ş.T., 2022. Mechanism of Generation and Propagation Characteristics of Coastal Trapped Waves in the Black Sea. Ocean Science, 18(4), pp. 1081-1091. doi:10.5194/os-18-1081-2022
  14. Goryachkin, Yu.N. and Ivanov, V.A., 2006. Black Sea Level: Past, Present, Future. Sevastopol: ECOSI-Gidrofizika, 210 p. (in Russian).
  15. Ilyin, Yu.P., Repetin, L.N., Belokopytov, V.N., Goryachkin, Yu.N., Dyakov, N.N., Kubryakov, A.A. and Stanichny, S.V., 2012. Hydrometeorological Conditions of the Ukrainian Seas. Vol. 2. The Black Sea. Sevastopol: ECOSI-Gidrofizika, 421 p. (in Russian).
  16. Fomicheva, L.A., Rabinovich, A.B. and Demidov, A.N., 1991. [Sea Level]. In: E. N. Altman and A. I. Simonov, eds., 1991. Hydrometeorology and Hydrochemistry of Seas in the USSR. Vol. IV. Black Sea. Issue 1. Hydrometeorological Conditions. Leningrad: Gidrometeoizdat, pp. 329-354 (in Russian).
  17. Mungov, G., 1981. [Study of Sea Level Fluctuations along the Bulgarian Coast in a Medium- Scale Frequency Range]. Hidrologija i Meteorologija, 30(2), pp. 20-32 (in Bulgarian).
  18. Krasteva, E., 1981. Diurnal Amplitudes of the Black Sea Level near Varna and Burgas. Problems of Geography, 2, pp. 15-24 (in Bulgarian).

Download the article (PDF)