Reproduction of Variability of the Black Sea Level and Pycnocline Characteristics Based on the Adaptive Statistics Method

P. N. Lishaev✉, V. V. Knysh, G. K. Korotaev

Marine Hydrophysical Institute, Russian Academy of Sciences, Sevastopol, Russian Federation

✉ e-mail: pavellish@mail.ru

Abstract

Retrospective analysis of the Black Sea hydrophysical fields (1993–2014) is carried out including assimilation of the three-dimensional fields of the temperature and salinity pseudo measurements reconstructed before in the model on the horizons within the layer 63–500 m by the adaptive statistics method. To compare root-mean-square deviations of the temperature and salinity fields from the observations, the reanalysis data (1993–2012) comprising assimilation of the temperature and salinity unperturbed profiles in the model are used. Variability of temperature and salinity (density) profiles in the main pycnocline is reproduced more accurately in the reanalysis for 1993–2014. Root-mean-square deviations of the sea level fields (resulted from the reanalysis for 1993–2014) from the altimetry ones in the first decade of seasonal and inter-annual variability are smaller than those (estimated in the same way) obtained from the reanalysis data for 1992–2015 in which the AVISO data and the sea surface temperature are assimilated. The root-mean-square deviations of the sea level increase in the second decade of the period. It is explained by the fact that decrease of the training set is accompanied by lowering of accuracy in reconstructing the fields of the temperature and salinity pseudo-measurements based on the altimetry and Argo buoys’ data. Synoptic variability of the sea currents’ fields in 1993–2014 is studied by analyzing the maps of the sea level integral dispersion. The values of sea level dispersion are found to be high on vast areas in the western and eastern parts of the basin. It is conditioned by generation and movement of the Sevastopol anticyclone, formation of synoptic vortices in the southwestern region of the western cyclonic water cycle, dynamics and evolution of the Caucasian anticyclonic vortices and the Batumi anticyclone. The local area to the northwest off Sinop is also noted.

Keywords

reanalysis, pseudo measurements, adaptive statistics, RMS deviation, synoptic variability, integral dispersion

Acknowledgements

The investigation results represented in the section “Development of the method of joint assimilation of the Black Sea altimetry level and the limited measurement data of the Argo profiling floats” are obtained within the framework of the state task on the theme No. 0827-2014-0011 “Studies of regularities of the marine environment state changes based on the operational observations and the nowcast, forecast and reanalysis system data on the marine environment state” (code “Operational oceanography”). The rest of the investigation results sited in the paper are obtained at the RFBR financial support, grant No. 16-05-00621. The authors express their deep gratitude to V. L. Dorofeev for providing the data on the Black Sea level reconstructed based on reanalysis of the hydrophtsical fields for 1992 – 2015.

Original russian text

Original Russian Text © P. N. Lishaev, V. V. Knysh, G. K. Korotaev, 2018, published in MORSKOY GIDROFIZICHESKIY ZHURNAL, Vol. 34, Iss. 4, pp. 271–282 (2018)

For citation

Lishaev, P. N., Knysh, V. V. and Korotaev, G. K., 2018. Reproduction of variability of the Black Sea level and pycnocline characteristics based on the adaptive statistics method. Physical Oceanography, 25(4), pp. 251-261. doi:10.22449/1573-160X-2018-4-251-261

DOI

10.22449/1573-160X-2018-4-251-261

References

  1. Korotaev, G.K., Lishaev, P.N. and Knysh, V.V., 2015. Technique of the Black Sea Temperature and Salinity Measurement Data Analysis Using Dynamic Altimetry Level. Physical Oceanography, [e-journal], (2), pp. 24-38. doi:10.22449/1573-160X-2015-2-24-38
  2. Korotaev, G.K., Sarkisyan, A.S., Knysh, V.V. and Lyshaiev, P.N., 2016. Reanalysis of Seasonal and Interannual Variability of Black Sea Fields for 1993-2012. Izvestiya, Atmospheric and Ocean Physics, [e-journal] 52(4). pp. 418-430. https://doi.org/10.1134/S0001433816040071
  3. Korotaev, G.K., Lishaev, P.N. and Knysh, V.V., 2016. Reconstruction of the Three-Dimen-sional Salinity and Temperature Fields of the Black Sea on the Basis of Satellite Altimetry Measurements. Izvestiya, Atmospheric and Oceanic Physics, [e-journal] 52(9), pp. 961-973. https://doi.org/10.1134/S0001433816090152
  4. Knysh, V.V. and Lishaev, P.N., 2016. Improvement of the Method for Reconstructing the Temperature and Salinity Three-Dimensional Fields of the Black Sea Based on Insufficient Measurements and Altimetry. Physical Oceanography, [e-journal] (6), pp. 3-14. doi:10.22449/1573-160X-2016-6-3-14
  5. Korotaev, G.K., Knysh, V.V., Lishaev, P.N. and Demyshev, S.G., 2018. Application of the Adaptive Statistics Method for Reanalysis of the Black Sea Fields Including Assimilation of the Temperature and Salinity Pseudo-Measurements in the Model. Physical Oceanography, [e-journal] 25(1), pp. 36-51. doi:10.22449/1573-160X-2018-1-36-51
  6. Evensen, G., 2003. The Ensemble Kalman Filter: Theoretical Formulation and Practical Implementation. Ocean Dynamics, [e-journal] 53(4), pp. 343-367. doi:10.1007/s10236-003-0036-9
  7. Belyaev, K.P., Tanajura, C.A.S. and Tuchkova, N.P., 2012. Comparison of Methods for ARGO Drifters the Data Assimilation into a Hydrodynamic Model of the Ocean. Oceanology, [e-journal] 52(5), pp. 593-603. doi:10.1134/S0001437012050025
  8. Kaurkin, M.N., Ibrayev, R.A. and Belyaev, K.P., 2016. Data Assimilation into the Ocean Dynamics Model with High Spatial Resolution Using Ensemble Optimal Interpolation (EnOI). Oceanology, [e-journal] 56(6), pp. 774-781. doi:10.1134/S0001437016060059
  9. Gejadze, I.Yu., Le Dimet, F.-X. and Shutyaev, V., 2008. On Analysis Error Codispersions in Variational Data Assimilation. SIAM Journal on Scientific Computing, [e-journal] 30(4), pp. 1847-1874. https://doi.org/10.1137/07068744X
  10. Zalesny, V.B., Gusev, A.V. and Moshonkina, S.N., 2013. Numerical Model of the Hydrodynamics of the Black Sea and the Sea of Azov with Variational Initialization of Temperature and Salinity. Izvestiya, Atmospheric and Oceanic Physics, [e-journal] 49(6), pp. 642-658. https://doi.org/10.1134/S0001433813060133
  11. Agoshkov, V.I., Parmuzin, E.I. and Shutyaev, V.P., 2013. Observational Data Assimilation in the Problem of Black Sea Circulation and Sensitivity Analysis of Its Solution. Izvestiya, Atmospheric and Oceanic Physics, [e-journal] 49(6), pp. 592-602. https://doi.org/10.1134/S0001433813060029
  12. Ilyin, Yu.P., Repetin, L.N., Belokopytov, V.N., Goryachkin, Yu.N., Dyakov, N.N., Kubryakov, A.A. and Stanichnyi, S.V., 2012. Gidrometeorologicheskiye Usloviya Morey Ukrainy. Tom 2. Chernoye More [Hydrometeorological Conditions of the Seas of Ukraine. Vol. 2. Black Sea]. Sevastopol, 421 p. (in Russian).
  13. Demyshev, S.G., 2012. A Numerical Model of Online Forecasting Black Sea Currents. Izvestiya, Atmospheric and Oceanic Physics, [e-journal] 48(1), pp. 120-132. https://doi.org/10.1134/S0001433812010021
  14. Pacanowski, R.C. and Philander, S.G.H., 1981. Parametrization of Vertical Mixing in Numerical Models of Tropical Oceans. Journal of Physical Oceanography, [e-journal] 11, pp. 1443-1451. doi:10.1175/1520-0485(1981)011<1443:POVMIN>2.0.CO;2
  15. Lishaev, P.N., 2014. Reanalysis of the Hydrophysical Fields of the Black Sea with Assimilation of Average Monthly Salinity and Temperature Profiles in 1980-1993. In: MHI, 2014. Sovremennoe Sostoyanie i Perspektivy Narashchivaniya Morskogo Resursnogo Potentsiala Yuga Rossii: Tezisy Dokladov Mezhdunarodnoj Nauchnoj Konferentsii, pgt Katsiveli, 15-18 Septembera 2014. [Current State and Prospects for Building up the Marine Resource Potential of Southern Russia: Proceedings of International Scientific Conference. Russia, Katsiveli, 15-18 September 2014]. Sevastopol: ECOSI-Gidrofizika, pp. 186-188 (in Russian).
  16. Berrisford, P., Dee, D., Fielding, K., Fuentes, M., Kållberg, P., Kobayashi, S. and Uppala, S., 2009. The ERA-Interim Archive: Version 1.0. ERA Report Series. No. 1. Berkshire, United Kingdom: ECMWF, 16 p. Available at: https://www.ecmwf.int/sites/default/files/elibrary/2009/8173-era-interim-archive.pdf [Accessed: 10 February 2018].
  17. Dorofeyev, V.L. and Sukhikh, L.I., 2017. Nekotoryye Tendentsii Dolgovremennoy Izmenchi-vosti Gidrofizicheskikh Poley Chernogo Morya po Rezul'tatam Reanaliza [Some Trends in the Long-Term Variability of the Black Sea Hydrophysical Fields on the Results of the Reanalysis]. Ekologicheskaya Bezopasnost' Pribrezhnoy I Shel'fovoy Zon Morya [Ecological Safety of Coastal and Shelf Zones of Sea], (1), pp. 15-22 (in Russian).
  18. Dorofeev, V.L. and Sukhikh, L.I., 2017. Study of Long-term Variability of Black Sea Dynamics on the Basis of Circulation Model Assimilation of Remote Measurements. Izvestiya, Atmospheric and Oceanic Physics, [e-journal] 53(2), pp. 224-232. https://doi.org/10.1134/S0001433817020025
  19. CNES, 2018. AVISO+ – Satellite Altimetry Data [site]. [on-line] Available at: http://www.aviso.oceanobs.com [Accessed: 5 December 2017].
  20. Blatov, A.S., Bulgakov, N.P., Ivanov, V.A., Kosarev, A.N. and Tuzhilkin, V.S., 1984. Izmenchivost' Gidrofizicheskikh Poley Chernogo Morya [Variability of the Hydrophysical Fields of the Black Sea]. Leningrad: Gidrometeoizdat, 239 p. (in Russian).
  21. Kordzadze, A.A. and Demetrashvili, D.I., 2011. Regional'naya Operativnaya Sistema Prognoza Sostoyaniya Vostochnoy Chasti Chernogo Morya [Regional Operational Forecasting for the Easternmost Part of the Black Sea]. In: MHI, 2011. Ekologicheskaya Bezopasnost' Pribrezhnykh i Shel'fovykh Zon i Kompleksnoe Ispol'zovanie Resursov Shel'fa [Ecological Safety of Coastal and Shelf Zones and Comprehensive Use of Shelf Resources]. Sevastopol: ECOSI-Gidrofizika. Iss. 25(2), pp. 136-146 (in Russian).
  22. Korotaev, G.K., Saenko, O.A. and Koblinsky, C.J., 2001. Satellite Altimetry Observations of the Black Sea Level. Journal of Geophysical Research, [e-journal] 106(C1), pp. 917-933. https://doi.org/10.1029/2000JC900120
  23. Demyshev, S. and Dymova, O., 2011. Modelirovaniye Tsirkulyatsii Chernogo Morya s Vysokim Prostranstvennym Razresheniyem [High Resolution Modeling of the Black Sea Circulation]. In: MHI, 2011. Ekologicheskaya Bezopasnost' Pribrezhnykh i Shel'fovykh Zon i Kompleksnoe Ispol'zovanie Resursov Shel'fa [Ecological Safety of Coastal and Shelf Zones and Comprehensive Use of Shelf Resources]. Sevastopol: ECOSI-Gidrofizika. Iss. 25(2), pp. 114-135 (in Russian).

Download the article (PDF)