Современные проблемы дистанционного зондирования Земли из космоса. 2020. Т. 17. № 6. С. 70-75
Identification of large turbulent structures from simultaneous field and satellite measurements
A.M. Chukharev
1, 2 , O.I. Pavlenko
1 1 Marine Hydrophysical Institute RAS, Sevastopol, Russia
2 Sevastopol State University, Sevastopol, Russia
Одобрена к печати: 15.09.2020
DOI: 10.21046/2070-7401-2020-17-6-70-75
The existence of relatively large formations in developed turbulent flows is an important distinguishing feature and it requires a special approach to modeling. A significant part of the energy carried by large structures significantly affects the processes of interaction between the atmosphere and the ocean, modulating the intensity of heat and momentum flows. Experimental data obtained by contact method at the sub-satellite polygon demonstrate the presence of submesoscale structures in the marine boundary layer, identified by various methods. Wavelet analysis is the most informative method available for analysing in-situ data. The instrument ensemble used on the oceanographic platform, consisting of Sigma, ADCP and Vostok-M instruments, allows us to study the effects associated with both the vorticity of the wind wave field and with larger-scale formations with multi-day periods. A wide set of measured hydrometeorological parameters makes it possible to evaluate the coherence functions between various physical characteristics, including the intensity of turbulent flows. A direct comparison of the results obtained by various methods unfortunately does not give unambiguous conclusions. Both good quantitative and qualitative agreement and differences between the results are observed. The scale of the structures identified by the intensity of turbulence ranges is from 2 to 42–44 hours (linear scale is 0.3–15 km), and scales determined by wind speed and current velocity are over 70 hours. In most cases a high correlation of the detected structures in the marine environment with atmospheric processes.
Ключевые слова: field measurements, marine turbulence, turbulent structures, dissipation rate, wavelet analysis
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