共查询到20条相似文献，搜索用时 203 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.
É. N. Mikhailova V. A. Ivanov A. I. Kubryakov N. B. Shapiro 《Physical Oceanography》2000,10(4):305-311
We use mathematical simulation to study the response of the sea in the region of the Zmeiny Island to the action of winds
of various directions. We describe the processes of reconstruction of circulation and thermohaline structure of waters and,
in particular, the location and dimensions of the zones of upwelling and downwelling caused by water surges depending on the
direction of the wind.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
3.
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
4.
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
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.
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
7.
S. I. Kondratev V. V. Dolotov Yu. G. Moiseev Yu. T. Shchetinin 《Physical Oceanography》2000,10(3):257-272
We performed a search for local coastal submarine springs of fresh water in the region from Cape Feolent to Cape Sarych (down
to an isobath of 40m). Stable submarine springs of brackish water with the minimum salinity of 5.5‰ and the minimum total
output of 30,000 m3/day were discovered only near the west wall of Cape Aiya. It is shown that brackish waters discharging from these springs
spread over the sea surface in the form of a thin layer (up to 1 m in thickness) characterized by lower salinity, higher transparency,
and an elevated content of silicic acid. We make a conjecture that the appearance of 2–3-m-thick layers of water with higher
transparency and lower salinity at depths of 5–8 m is explained by the discharge of unknown bottom springs of underground
fresh water.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
8.
N. P. Bulgakov S. N. Bulgakov V. N. Davydova A. Z. Martinez 《Physical Oceanography》2000,10(3):233-243
On the basis of the data of thein situ measurements of current velocities and other basic hydrophysical parameters (temperature and salinity) performed in the course
of Cruise 41 of the R/VAkademik Vernadsky, we analyze the variability and stability of the North Brazil Current in winter. We also study the possibility of the influence
of the baroclinic component of the horizontal drop of hydrostatic pressure on the vertical profile of the current velocity
and estimate the intensity of the transport of waters.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
9.
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
10.
V. I. Man’kovsky 《Physical Oceanography》2001,11(5):491-494
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 相似文献
11.
N. P. Bulgakov V. V. Ukrainsky Yu. I. Popov P. D. Lomakin Yu. V. Artamonov 《Physical Oceanography》2001,11(5):447-457
On the basis of the data of the complex oceanographic experiment carried out in the course of the second Ukrainian Antarctic
expedition in March 1998, we study the structure and kinematics of waters in the region of the archipelago of Argentine Islands.
The regularities of thermohaline stratification of waters are discovered. We determine the most important environmental parameters
premoting the variability of hydrophysical fields on time scales varying from several days up to a week, analyse the data
of actual observations over the currents, and estimate the relative contribtions of diurnal and semidiurnal tidal waves to
the total dispersion of hydrophysical parameters of the environment. The residual currents are filtered out. We propose a
hypothesis about the mechanism of their formation. Various types of tidal currents are revealed and the directions of propagation
of diurnal and semidiurnal tidal waves are determined.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
12.
We describe the hydrological structure of waters of the Persian Gulf and its seasonal variability according to the data of
CTD surveys carried out in February–June 1992 in the course of the cruises of the NOAA R/VMt. Mitchell aimed at the analysis of the consequences of the ecological catastrophe caused by the spread of oil spots formed as a result
of war operations in the Persian Gulf in 1991.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
13.
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
14.
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
15.
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
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.
We the discuss the results of modelling wind currents in the system of Sevastopol bays. Numerical calculations are carried
out according to the model of Felzenbaum. It is shown that the decisive role in the formation of distinctive features of circulation
of waters and the essentially three-dimenstional character of currents in this part of the sea is played by the bottom topography
and the direction of winds. These distinctive features are demonstrated for the cases where the motion is induced by the northeast
and northwest winds. In the Sevastopol bays, we discovered the existence of jet longshore currents, vortex character of integral
circulation, and intense processes of upwelling and downwelling.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
18.
With the help of a combined model of wind and waves, we study the influence of films of surfactants on the spectrum of short
wind waves and the parameters of the lowest layer of the atmosphere. It is shown that the films of surfactants decrease the
roughness of the sea surface as a result of suppression of short wind waves, which decreases the coefficient of resistance
of the sea surface and the coefficient of turbulent heat exchange. The maximum influence of films on the exchange coefficients
is attained forU∼10 m/s. In this case, the relative decrements of the coefficients of resistance and turbulent heat exchange are equal to
15 and 9%, respectively.
Translated by Peter V. Malyshev and Dmitry V. Malyshev UDC 551.46 相似文献
19.
We analyze the influence of a rift in an ice field on the propagation of flexural gravitational waves in a basin of finite
constant depth. The ice cover is simulated by two floating semiinfinite elastic plates of different thickness. We studied
the dependence of the amplitude coefficients of reflection and transmission of waves incident on the rift on the frequency
of running waves, the thickness of ice on both sides of the rift, and the type of contact boundary conditions at the rift.
Translated by Peter V. Malyshev and Dmitry, V. Malyshev 相似文献
20.
In the coastal zone, as a result of mixing of waters, it is difficult to identify turbulent phenomena with a spatial scale
of 0.1–1 km accompanied by strong vertical flows according to the data of measuring temperature. On the basis of the data
of direct measurements, it is shown that turbulent structures are well pronounced in the field of breaking of wind waves.
We deduce empirical estimates of the response of the intensity of wave breaking to the magnitude of divergence of the current
and develop a theoretical model of the influence of inhomogeneities of currents on wave breaking capable of describing the
experimental data.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献