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551.465For the first time, an acoustic Doppler current profiler (ADCP) produced by the RDI is used in the water area of the Black Sea in the lowered mode. This direction in the application of acoustic Doppler current profilers is now in the stage of development and verification of various procedures of measurements with subsequent data processing and enables one to get the distributions of current velocities down to depths of 1000-6000 m depending on the modification of the instrument. We describe the procedures of measurements performed with the help of the ADCP in the lowered mode in the course of an expedition and the stages of processing of the primary data based on the experience of application of similar acoustic current profilers at the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences accumulated in the 1980s. We generalize the experience of application of ADCP under the hydrological conditions of the Black Sea, propose the algorithms of data processing, present the profiles of absolute current velocity at several stations, compare these profiles with the geostrophic velocities, and determine the deepwater structure of the field of currents in a shelf-open-sea section made along 31.17°E.

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The profiles of absolute current velocity obtained by using a lowered acoustic doppler current profiler (LADCP) are presented. In the course of the BSERP-3 expedition, the measurements were carried out in the regions of the Rim Current, anticyclonic eddy, and northwest shelf. In the core of the Rim Current, a unidirectional motion of waters is traced in layers below the main pycnocline down to depths greater than 500 m. Its characteristic velocity can be as high as 0.08 m/sec. It is shown that the direct action of the eddy is detected in the shelf region at distances larger than 20 km from the outer edge of the shelf in the zone bounded by an isobath of 100 m. The formation of multilayer vertical structures in the field of current velocities is revealed in the region of interaction of the anticyclonic eddy with irregularities of the bottom on the side of the shelf. A two-layer structure of currents with specific features in the layer of formed seasonal pycnocline is observed in the region of the shelf down to an isobath of 100 m. The profiles of the moduli of vertical shears of currents averaged over the casts ensemble are presented for the abyssal and shelf parts of the sea. It is shown that the shears induced by the geostrophic currents and wave processes in the region of the main pycnocline are comparable. Below the pycnocline, the shears are mainly determined by the wave processes.

The article presents the core results of lowered acoustic Doppler current profiler (LADCP) applied in the Black Sea within [2004][2005][2006][2007][2008][2009][2010][2011][2012][2013][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/m 3 (~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 wellseparated 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 m 2 /s) and increases with depth to achieve value 210 -5 m 2 /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.