Generation of internal waves in the sea by local perturbations of wind and density flows on the surface

On the basis of a nonlinear model taking into account viscosity, density diffusion, and currents, we perform the numerical analysis of propagation of perturbations formed in the abyssal part of the Black Sea as a result of the action of tangential wind stresses or density flows in the form of a strip on the sea surface. It is shown that, in the course of time, in the region of the bottom slope, these perturbations generate a train of waves in the sea, which causes oscillations of the fields of density and currents. There are some differences between the generation of internal waves by the flows of density and the wind. Unlike the wind action, in the presence of flows of density in the upper layer in the region of the strip, the initial period of generation is characterized by the formation of intense perturbations without train structure. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Numerical investigation of the influence of various factors on the propagation and transformation of solitary waves in the sea

For various stratifications and different types of bottom patterns we study the transformations of solitary perturbations of density appearing in the depth of the sea. In the two-dimensional case, under the assumption that the average dynamic characteristics weakly vary in time as compared with the wave characteristics, we deduce the equations for mean currents and waves taking into account vertical and horizontal viscosity and the diffusion of density. Numerical examples show that the stratification, bottom topography, nonlinearity, mean currents, and dissipation strongly affect both the process of splitting of a solitary wave into wave trains and their amplitude and length. The wave currents exhibit the oscillatory (train-like) character. It is emphasized that, in the case of propagation of solitary perturbations of density with dissipation, it is also important to take into account the combined influence of nonlinearity, currents, bottom topography, and stratification. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Surface gravity waves formed in the process of motion of an ellipsoidal body submerged in the liquid

We study the problem of flow around an ellipsoidal body submerged in a liquid half space and obtain the solution for the free wave surface. The results of numerical analysis reveal the existence of a great variety of modes of motion characterized by substantially different shapes of the free surface. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Relationship between the depth of visibility of Secchi disk and biooptical characteristics of the Black-Sea waters

We present the parameters of empirical relationships between the depth of visibility of Secchi disk and optical and biological characteristics of the Black-Sea surface waters. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

A model of the evolution of vertical thermohaline inhomogeneities of an oceanic thermocline taking into account the effects of double diffusion

We construct a numerical model of the evolution of the structure of an oceanic thermocline in the presence of “salt-finger” convection. The model explains the formation of a piecewise homogeneous vertical structure of the temperature and salinity fields in the ocean. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

On the influence of a diurnal baroclinic tide on the diffusion of an impurity

We investigate the influence of baroclinic tidal waves on the diffusion of an impurity spot in a continuously stratified liquid. The equation of turbulent diffusion is solved numerically by taking into account the wave currents. We establish the dependences of the characteristics of the diffusion process on the parameters of the baroclinic wave and the location of the impurity spot. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Oceanological conditions in the regions of underwater mountains in the Pacific Ocean

We study distinctive features of the oceanological conditions in the regions of underwater mountains. These conditions are used as a basic for the selection of hydrological and biological subcomplexes (aqualandscapes) of these regions. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Effect of the flow conditions on the metrological characteristics of a contact acoustic current meter

We discuss the results of metrological testing of a four-base acoustic current meter performed in a hydrodynamic basin, consider methodological problems encountered in the process of measurements and data processing, and present the experimental dependences of the systematic and random components of the measurement errors on the velocity and direction of the flow. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Mass transfer by nonlinear waves in a basin with floating broken ice

We study the influence of floating broken ice on the mean nonzero displacements of liquid particles in nonlinear running surface waves. The analysis is performed on the basis of a uniform asymptotic expansion (up to the quantities of the third order of smallness as compared with the potential of the velocity of motion of liquid in a basin of finite depth) obtained by the method of multiple scales. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Application of a probabilistic method to the analysis of accumulation of toxic substances by marine organisms

The process of accumulation of toxic substances by marine organisms is studied on the basis of the kinetic theory of systems of macroscopic particles (V. I. Belyaev, 1987). The use of stochastic equations makes it possible to evaluate the degree of accumulation of toxic substances in marine organisms and take into account random variations of their concentrations in marine environments. Translated by Peter V. Malyshev and Dmitry V. Malyshev.     

Physical and hydrological characteristics of climatic frontal zones in the Tropical Atlantic

Climatic frontal zones are selected in the thermohaline fields of the Tropical Atlantic by analyzing the many-year-average seasonal database reduced to the nodes of a one-degree grid. We determine physical characteristics of the frontal zones, study their spatial and temporal variability, and reveal basic regularities of the appearance of frontal zones in the fields of thermohaline characteristics. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Computational algorithm for the evaluation of inclinations of the level in the problems of the dynamics of basins

We develop a method for the evaluation of inclinations of the level, which enables one to find them with high accuracy. The reliability of this method is tested by comparing the numerical solutions for inclinations of the level with analytic expressions. It is shown that the system of coupled equations for inclinations of the level can be decomposed into two independent equations with sufficiently high accuracy. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Turbulent diffusion of impurities in the ocean in the presence of internal waves

We study the influence of baroclinic tidal waves on the diffusion of an impurity spot in a continuously stratified fluid. The equation of turbulent diffusion is solved numerically by taking into account the wave currents. We establish the dependences of the characteristics of the diffusion process on parameters of baroclinic waves and the location of the impurity spot. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Laser diagnostics of the composition and salinity of mineralized waters

We study the possibilities of the method of laser diagnostics of the composition of multicomponent electrolytic solutions. In our experiments, we used a four-mirror phase-retarded interferometer operating at three wavelengths from the visible range. For three-component solutions of chloride salts, we determined partial sensitivities of the measuring system to changes in the concentrations of each electrolyte for each of the indicated wavelengths. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Seiches in a circular basin of variable depth

Free waves (seiches) in a circular basin of variable depth are studied numerically within the framework of the linear theory of long waves taking into account the action of the Coriolis force. We determine the frequencies of axisymmetric and circular waves, study the structure of the modes of elevation of the free surface and wave velocities, and establish the dependences of the phase velocities of circular waves on the number of mode and wavelength. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Evaluation of the submarine discharge of karst waters in the region of Cape Aiya

For the submarine springs of underground water located in the karst cavities of Cape Aiya, we suggest a solution based on the modification of the model of flow rate of water and application of the formulas of mixing. We also give methodical recommendations helpful for the reliable determination of empirical parameters under thein situ conditions. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Distributed thermoprofilometers and their capabilities in oceanographic investigations

We describe the principles of design of distributed thermoprofilometers and analyze their characteristics and the required hardware, algorithms, and software. The capabilities of these instruments in the investigation of temperature fields, vertical displacements, and the parameters of internal waves are evaluated. The results of measurements and numerical calculations are presented. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Generation of internal waves by a barotropic tide in the coastal zone

Within the framework of the linear theory of long waves, we study internal waves generated by a barotropic tide in a two-layer ocean of variable depth taking into account the influence of the Coriolis force. Barotropic waves run over an extended unevenness of the bottom at an arbitrary angle. This unevenness is regarded as a model of the continental slope and shelf. We establish the dependences of the amplitudes of generated internal waves on the angle of incidence of the barotropic tide, topography of the bottom, and stratification. Translated by Peter V. Malyshev and Dmitry V. Malyshev     

Modelling of the propagation of passive impurities in Sevastopol bays

We discuss the results of numerical experiments modelling the process of propagation of passive impurities from the Karantinnaya Bay caused by steady wind currents and turbulent diffusion. The currents are computed according to the Felzenbaum model for the cases of northeast and north-west winds [1, 2]. We analyse specific features of the space and time distribution of the impurities caused by the three-dimensional character of the currents. Translated by Peter V. Malyshev and Dmitry V. Malyshev