Physical Oceanography, Vol.
INVESTIGATION OF THE INFLUENCE OF CYCLONIC DISTURBANCES
ON THE DYNAMIC PROCESSES AND THE EVOLUTION OF IMPURITIES
IN THE SEA OF AZOV IN THE PRESENCE OF STATIONARY CURRENTS
V. A. Ivanov, V. V. Fomin, L. V. Cherkesov, and T. Ya. Shul’ga
A three-dimensional nonlinear mathematical model is used to study the dynamic processes under
the action of cyclonic disturbances in the field of stationary wind in the Sea of Azov and the spe-
cific features of transformation of the impurities. The results of numerical calculations enable us
to conclude that the maximum velocities of currents generated by a cyclone depend on the direc-
tion of its motion. It is shown that the cyclones moving westward generate currents with higher
maximum velocities than the cyclones of other directions. It is also demonstrated that the motion
of atmospheric disturbances leads to a significant enlargement of the area of propagation of pol-
lutants as compared with the case of action solely of stationary currents. The influence of the
velocities of stationary currents on the maximum current velocities caused by the passage of a
cyclone is also analyzed.
The investigation of the dynamics of waters in sea basins and the prediction their future changes are urgent
problems of the contemporary oceanology connected with the process of global warming and permanently
increasing anthropogenic influence. In these investigations, special attention is given to the analysis of the most
probable scenarios of propagation of impurities whose evolution mainly occurs as a result of their transfer by
currents. The Sea of Azov is a relatively small and shallow basin and, hence, the currents are formed in it, first
of all, under the direct action of wind and bottom topography. The results of numerical simulations described in
[1–3] show that the dynamics of waters becomes more intense in the presence of cyclones moving over the Sea
of Azov. Therefore, the analysis of the influence of atmospheric anomalies in the form of cyclones on the circul-
ation of waters and propagation of impurities in this basin is of significant interest.
There are numerous works dealing with the numerical simulation of the dynamics of waters in the Sea of
Azov based on the application of the three-dimensional nonlinear
σ-coordinate model . Thus, the principal
characteristics of the wind currents and surge processes are studied for typical stationary wind fields in  and,
for nonstationary winds uniform over the space, in . In , one can also find the results of evaluation of the
time of complete dispersion of the impurity, the maximum polluted area, and the transformation of impurities in
the presence of stationary currents. In , the same processes are studied under the action of variable winds.
In the present work, the indicated mathematical model is applied to the investigation of the influence of cy-
clonic disturbances in the field of stationary currents on the dynamics of waters and transformations of passive
impurities in the Sea of Azov. The results of numerical calculations are presented for various parameters of the
Statement of the Problem. Boundary and Initial Conditions
We introduce a coordinate system in which the
x-axis is directed eastward, the
y-axis is directed northward,
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol, Ukraine.
Translated from Morskoi Gidrofizicheskii Zhurnal, No.
12–25, March–April, 2009.
Original article submitted September 7,
2007; revision submitted September 18, 2007.
72 0928-5105/09/1902–0072 © 2009 Springer Science+Business Media, Inc.