共查询到20条相似文献，搜索用时 875 毫秒
1.
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
2.
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
3.
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
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.
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
6.
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
7.
On the basis of the available literature data, we analyze basic classes of organic compounds dissolved in seawater and study
the transformations of proteins, carbohydrates, and lipids produced in the process of photosynthesis in seawater and their
behaviour in river water and estuaries of the Black Sea. We also discuss the causes and distinctive features of the processes
of production and destruction in the Black Sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
8.
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
9.
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
10.
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
11.
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
12.
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
13.
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
14.
15.
On the basis of the generalized data of multiannual observations (1985–1994), we analyze the seasonal variability of the vertical
and spatial distributions and composition (Csos, Nsos, Csos/cha, and C/N) of suspended organic substances (SOS) in the shelf zone and in the upper active layer of the abyssal part of the
Black Sea. The results of our analysis enable us to conclude that only a narrow coastal band of the shelf in the northwest
and west parts of the sea suffers to an extremely pronounced anthropogenic impact, which manifests itself in a significant
increase in the mass of suspended organic substances. The formation of new organic substances and, hence, the mass of suspended
organic substances in these regions attain the level of eutrophic waters in the late-spring and summer periods. In the open-sea
region, the anthropogenic impact is less pronounced and the spatial distribution of suspended organic substances is determined
by the general dynamics of waters and the intensity of phytoplankton production.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
16.
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
17.
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
18.
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
19.
By analyzing, as an example, the data of observations of the Black Sea from the space in autumn 1998, we conclude that, in
some cases, the atmospheric distortions manifest themselves in all measuring channels of SeaWiFS instruments and lead to significant errors in determining the concentration of chlorophyll according to the standard NASA algorithm. After additional rejection of the data with negative values of the spectral brightness of the sea surface at a
wavelength of 412 nm, the results of evaluation the concentration of chlorophyll are in good agreement with the available
data of direct measurements. We also present a detailed discussion of some specific features of operation of the NASA algorithm of atmospheric correction playing an important role in the interpretation of the data of observations of the Black
Sea.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 68–79, March–April, 2008. 相似文献
20.
We present a method for the determination of the trajectory of a sounding instrument and its drift velocity in the field of
currents nonuniform in depth and develop special software for IBM/PC compatible computers. The proposed method and software
are checked by using the well-known analytic solution of a similar problem given by Academician A. N. Krylov. We also consider
some special examples of application of the developed method to the processing of the data of an OLT profilometer.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献