Physical Oceanography, Vol. 18, No. 6, 2008
EXPERIMENTAL AND FIELD RESEARCH
VERTICAL STRUCTURE OF THE FIELD OF CURRENT VELOCITIES
IN THE NORTHWEST PART OF THE BLACK SEA BASED ON THE
LADCP DATA FOR MAY 2004
E. M. Lemeshko,
A. N. Morozov,
S. V. Stanichnyi,
L. D. Mee,
and G. I. Shapiro
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
m. Its characteristic velocity can be as high as
m/sec. It is shown that the direct action of the eddy is detected in the shelf region at dis-
tances larger than
from the outer edge of the shelf in the zone bounded by an isobath of
m. The formation of multilayer vertical structures in the field of current velocities is re-
vealed 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
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 large-scale circulation in the northwest abyssal part of the Black Sea is characterized by the presence of
the Rim Current, its meanders, and eddy formations. The results of numerical modeling performed on the basis
of the climatic data give a smoothed picture of circulation but, at the same time, reveal noticeable space shifts of
the jet of Rim Current from season to season . The standard hydrological field surveys reveal more pro-
nounced variations of the space-and-time characteristics of the dynamics of waters . At present, the direct
measurements of current velocities capable of giving the objective description of the dynamics of waters are
mainly restricted to the use of buoy stations at fixed points of the region, which enables one to study solely the
time variations. The best possibility to get an actual picture of the existing space structure of the field of currents
in the analyzed region is to perform direct measurements of the profiles of currents as a part of field surveys.
The number of existing oceanographic instruments capable of measuring the profiles of currents from the board
of a drifting vessel is quite small. These are garlands of point current meters , sensing point current meters
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol, Ukraine.
University of Plymouth, Plymouth, UK.
Translated from Morskoi Gidrofizicheskii Zhurnal, No.
25–37, November–December, 2008. Original article submitted April 20,
2007; revision submitted August 1, 2007.
0928-5105/08/1806–0319 © 2008 Springer Science+Business Media, Inc. 319