共查询到20条相似文献，搜索用时 390 毫秒
1.
O. I. Efremov 《Physical Oceanography》2000,10(3):193-204
A method of statistical separation of fine-structure fluctuations according to their origin is applied to the analysis of
the characteristics of mixing in a layer located below the summer temperature minimum in the Black Sea. The simplification
of the procedure of numerical evaluation of the coefficient of vertical wave exchange enabled us to perform the comprehensive
fine-structure processing of the data of regular surveys of the Black Sea with an aim to determine the spatial distribution
of the field intensity of small-scale internal waves and the intensity of mixing caused by these waves in the analyzed layer.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
2.
We analyse the time variability of the fields of Cs-137 concentration in the surface waters of the Black and Mediterranean
Seas in 1986–1998. It is shown that more contaminated Black-Sea waters affect the levels of concentration of this radionuclide
in the east part of the Mediterranean Sea. We also study the influence of atmospheric processes and water exchange through
Bosporus on the radioecological situation in the east part of the Mediterranean Sea and its coastal area.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
3.
S. V. Motyzhev 《Physical Oceanography》2000,10(6):561-568
We present the results of drift experiments with 14LOBAN-TM buoys carried out for the first time in the Black Sea in 1987–1997. We analyze the specific features of application of buoys
in summer and winter. We present the main results of investigation of the Main Black Sea Current by drift methods and joint
processing of drift contact and remote infrared observations. We demonstrate the possibility of enhancement of the quality
of observations due to the application of SVPB drifters of new generation equipped with underwater sails and meters of atmospheric
pressure in the near-surface atmospheric layer.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
4.
We analyze geostrophic currents with nonmonotonic vertical profiles, of velocity and present the distributions of the density
of water and hydrostatic pressure corresponding to possible types of the vertical kinematic structure. To prove the existence
of the indicated complex layered structures, we use, the data of instrumentalin situ measurements of currents in the Black Sea and in the west part of the Tropical Atlantic.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
5.
We analyze oscillations of the Black Sea level at 43 points in the north part of the coast. At some points, the data of every-day
measurements are accumulated for more than 100 years. Actually, at all points with minor exceptions, we observe a general
trend toward an increase in the sea level. The amplitude of oscillations of the sea level about the average trend obeys a
normal distribution. We determine numerical characteristics of this distribution.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
6.
M. M. Divizinyuk 《Physical Oceanography》2001,11(5):473-481
We consider the results of instrumental investigations of specific features of reverberation in the Black Sea and obtain qualitative
dependences of the duration of volume reverberation on the parameters of the Black-Sea underwater sound channel, (width, drop
of the sound velocity, and dimensions of the inhomogeneities of stratification). We also analyse the behaviour of the intensity
of surface reverberation in the far-field zone of acoustic illumination and the influence of bottom reverberation on the detection
of underwater objects.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
7.
N. B. Shapiro 《Physical Oceanography》2000,10(6):513-531
We discuss the results of numerical experiments carried out within the framework of a new version of the quasiisopycnic model
of the Black Sea [1, 2]. We take into account the stochasticity of the wind stress, vertical shift of the flow velocity in
the upper quasihomogeneous layer, and diapycnic mixing. We generalize the procedure of “convective adjustment,” which enables
us to consider the propagation and transformation of waters of the Sea of Marmara. It is shown that the consideration of these
factors enables one to determine the structure and seasonal variability of hydrothermodynamic fields in the sea more correctly.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
8.
On the basis of processing and analysis of the results of many-year observations, we study the process of formation of dome-shaped
isosurfaces of hydrological and hydrochemical characteristics for all depths in the Black Sea. We estimate the roles of the
intensities of sources and sinks of heat and dissolved substances and the general picture of water circulation, vertical exchange,
meso- and small-scale anticyclonic vorticity, and mud and geothermal flows to the preservation of the dome-shaped form of
the isosurfaces of these characteristics.
Translated by Peter V. Malyshev and Dmitry V. Malyshev. 相似文献
9.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the
Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of
rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the
transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic
regime of the sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
10.
We discuss the results of analysis of published data and field and laboratory investigations aimed at the solution of the
problem of comparabilityof the results of detection of hydrogen sulfide in the Black Sea by spectrophotometric and iodometric
methods. We show that the reproducibility of the results of spectrophotometric analysis is higher than hat of the iodometric
method only in the case where the content of sulfide in a sample is less than 10–30 μMl−1. When larger concentrations are involved, the traditional iodometric analysis proves to be the most precise and reliable
method for the detection of hydrogen sulfide in the Black-Sea waters.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
11.
E. A. Agafonov S. T. Kaminsky A. S. Kukushkin Yu. A. Prokhorenko 《Physical Oceanography》2000,10(4):351-364
On the basis of the results of simultaneous observations of parameters of currents, attenuation factor of light, and temperature
performed aboard a moving vessel, we established the main characteristics and features of the circulation of waters and the
structure of transparency and temperature fields in the surface layer of the northwest part of the Black Sea. We investigate
the correlation between the variability of fluid dynamics and redistribution of transparency and temperature fields. The measured
currents are compared with those calculated using the actual field of atmospheric pressure during the time of observation.
It is shown that the results obtained in the areas of steady currents in the west and central regions are in good agreement.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
12.
I. E. Timchenko A. A. Primalenny V. D. Yarin E. F. Vasechkina E. M. Igumnova 《Physical Oceanography》2001,11(4):367-378
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of
the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption
(fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by
the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with
application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem,
which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge,
water exchange with the Black Sea, etc.).
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
13.
We analyze the dependence of climatic variations of the location of the upper boundary of the hydrogen-sulphide zone in the
Black Sea on the variations of the sea level and various types of atmospheric circulation (according to A.A. Girs). It is
discovered that the level of correlation between the indicated parameters is high and that the corresponding plots are in
good qualitative agreement. The accumulated results enable us to make an assumption that there exists an 80–100-yr cycle of
variation of all analyzed parameters and that the long-term variations of the location of the upper boundary of the hydrogen-sulphide
zone can be regarded as a manifestation of global climatic variations.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
14.
We propose a method for the adaptive numerical analysis of current velocities in a basin including a shelf zone and having
a lengthy open boundary with the sea, at which the current velocity is not given. This method is based on a multilayer quasiisopycnic
model. We use an approach according to which one introduces additional terms of the source type into the equations of heat
and salt transfer and the equation of evolution of the thicknesses of layers. We describe the results of calculations of the
current velocities in the northwest part of the Black Sea in June on the basis of climatic data. We also analyse specific
features of thermohaline and dynamic structure of waters.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
15.
We discuss the current state of the problem of experimental investigation of the bottom boundary layer of the Black Sea and
present the data on a new measuring complex (designed and constructed at the Marine Hydrophysical Institute and called the
OLT-D profilometer of the bottom layer) together with some results of its application. On the basis of the analysis of the
data on the distributions of geothermal fluxes and parameters of the bottom boundary layer in the deep-water part of the sea,
we deduce and justify the relations for the evaluation of the critical thickness of the bottom boundary layer as a function
of the intensities of geothermal fluxes. It is shown that the numerical results are in good agreement with the data of direct
measurements of the thickness of the bottom boundary layer.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
16.
We analyse the distribution of the dissolved forms of cadmium, lead, cobalt, copper, and manganese in the near-Danube part
of the Black Sea and in a section made at 45° 10′N in the autumn of 1997. It is shown that the discharge of rivers results
in the appearance of significant amounts of cadmium, lead, cobalt, copper, and manganese in the near-Danube region. Copper
is the most labile element in this collection of metals. Its behaviour is correlated with the vital activity of diatomic algae.
The distribution of dissolved manganese in the near-bottom region is correlated with the distribution of O2. Indeed, the elevated concentrations of manganese are observed in the regions with low concentrations of oxygen.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
17.
V. F. Ivanov 《Physical Oceanography》2001,11(5):425-437
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 相似文献
18.
S. F. Dotsenko 《Physical Oceanography》2000,10(6):485-493
We perform the numerical analysis of the intensification of tsunami waves in the course of their propagation from the open
part of the Black Sea to the shelf zone. For this purpose, we use a one-dimensional model of nonlinear long waves taking into
account the effect of bottom friction. We study four profiles of the bottom corresponding to the south coast of the Crimean
Peninsula and establish the predominant role of the bottom pattern and insignificant contribution of nonlinearity to the transformation
of waves in the process of their propagation in the direction of the coast. Down to depths of 50 m, all changes in the height
of waves are described by the Green law. For the evaluation of vertical run-up of waves, it is important to take into account
nonlinear effects. The highest vertical run-ups of waves are observed in the parts of the shelf zone located near Yalta and
Alushta.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
19.
Some results derived in the course of exploration of seawater dynamics over the Mediterranean and Black Seas shelf, conducted in the framework of the Black Sea and Internal Waves projects during the summer of 1991, are described.Translated by V. Puchkin. 相似文献
20.
V. I. Man'kovsky 《Physical Oceanography》2001,11(3):299-304
On the basis of the data of optical investigations performed in the Black Sea, we develop a method for the evaluation of the
spectral values of underwater quantum irradiance within the band of photosynthetically active radiation according to the depth
of visibility of a Secchi disk and the intensity of illumination of the sea in luxes. The method is based on the use of the
correlations between the following optical parameters: of the vertical daylight attenuation factor α with the depth of visibility
of a Secchi disk and of the spectral values of α(λ) within the band of photosynthetically active radiation with α(λmin) for sea waters. This method is applicable in the winter-spring period when the seasonal thermocline is absent, the upper
layers of the sea are mixed, and the vertical distribution of α is uniform.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献