Structure of the Black Sea Currents Based on the Results of the LADCP Observations in 2004–2014

• Main Authors: A.N. Morozov, E.M. Lemeshko, S.A. Shutov, V.V. Zima, D.V. Deryushkin
• Format: Article
• Language: English
• Published: Federal State Budget Scientific Institution «Marine Hydrophysical Institute of RAS» 2017-02-01
• Series: Physical Oceanography
• Subjects: lowered acoustic Doppler current profiler LADCP; vertical structure of currents; vertical shear; vertical mixing; bottom boundary layer; Black Sea
• Online Access: http://physical-oceanography.ru/repository/2017/1/en_201701_03.pdf

The article presents the core results of lowered acoustic Doppler current profiler (LADCP) applied in the Black Sea within 2004–2014. Average features of the vertical structure of currents in the upper 600 m layer are outlined. The linear relation between vertical distribution of kinetic energy isopycnically averaged over the station ensemble and density is established. This relation is traced till the isopycn occurrence depth with density of 17 kg/m3 (500 m). The mean current velocity has near constant value about 4 cm/s in lower depth layers (>500 m), which is in a good agreement with autonomic buoys data. The averaged profile of current velocity vertical shears shows two well- separated maxima in the seasonal and main pycnocline layers. LADCP derived velocity shears are more than ten times exceed the geostrophic current shears. Turbulent vertical mixing coefficient, calculated by the G89 model (Gregg 1989) demonstrates the denominated minimum in the permanent pycnocline (4∙10-6 m2/s) and increases with depth to achieve value 2∙10-5 m2/s at 450 m depth. The profile of current velocity averaged by the ensemble casts in the near bottom boundary layer demonstrates near logarithmic relation.