Statistical Analysis and Numerical Modeling of Hydrodynamical Sea Oscillation Parameters in Subinertial Range on the Crimean Shelf

Abstract

Subinertial waves at the Black Sea shelf have been thoroughly studied in the last decades from the theoretical, observational and experimental points of view. Results of numerical prognostic experiments on modeling of the Black Sea circulation based on thermo-hydrodynamic eddy-resolving MHI model are studied. Spectral peaks in the oscillations of the current velocity component vector, temperature, salinity and vertical velocity are identified for the selected stations by means of the Fourier spectral analysis. The obtained energy-transporting oscillations are interpreted using expert estimates and comparison with the previous research. Time range of numerical calculation is conditioned by availability of data on the mass and energy external flows (reanalysis of the atmosphere state). Hydrodynamic parameters for April, 2006 and May – September, 2013 are considered. It is noted that seasonal variability of stratification and the model high sensitivity to the wind effects condition spectral characteristics of the wave processes on sub-inertial scales and intensity of mixing of the upper mixed layer. Two main energy-carrying intervals where the oscillations are confidently reconstructed by the modelare pointed out: large-scale relatively slow movements with the periods from 4 to 7 days and short-period waves with the periods from 10 to 40 hours. Due to relatively smooth bathymetry, origins of the short-period oscillations are hard to trace.

Keywords

oscillation, internal waves, shelf, the Black Sea, numerical modeling, spectra.

DOI: 10.22449/1573-160X-2015-6-55-68

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