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1.
The method of two-dimensional isopycnic analysis is applied to study the distribution of inorganic phosphates and nitrates
in the Black Sea. The effect of winter-time ventilation in the central sea on the formation of chemical fields is examined,
as well as the outcropping of biogenic elements from the layer of high concentrations (σ
t∼14.5–16.0). It is demonstrated that the amount of nitrates entering the upper active layer of the sea as a result of winter-time
convective ventilation may attain values comparable with their overall annual input by river discharge, and that they control
the intensity of winter-spring phytoplankton blooming in the central sea. The spatial variability of the vertical phosphate
distribution is analysed. For the annual cycles with fairly cool winter conditions, an occurrence of three peaks on the phosphates
vertical profile in spring has been documented over a vast sea area where the rim current represents an external dynamic boundary.
Translated by Vladimir A. Puchkin. 相似文献
2.
Variability in water temperature, salinity and density was investigated based on field measurements near Anzali Port, in the
Southern Caspian Sea in 2008. Seasonal changes of seawater properties were mainly observed through the upper 100 m layer,
while below this layer seasonal variations of the parameters were minor. Vertical structure of the temperature in the southern
coastal waters of the Caspian Sea is characterized by a significant seasonal thermocline between 20–50 m depths with vertical
variation in temperature about 16°C in midsummer (August). Decrease of the thermocline occurs with the general cooling of
the air and sea surface water, and deepening of the mixed layer during late of autumn and winter. Seasonal averages of the
salinity were estimated in a range of 12.27–12.37 PSU. The structure of thermocline and pycnocline indicated agreement between
changes of temperature and density of seawater. Seasonal pycnocline was observed in position of the thermocline layer. 相似文献
3.
In this study, we develop a variable-grid global ocean general circulation model(OGCM) with a fine grid(1/6)°covering the area from 20°S–50°N and from 99°–150°E, and use the model to investigate the isopycnal surface circulation in the South China Sea(SCS). The simulated results show four layer structures in vertical: the surface and subsurface circulation of the SCS are characterized by the monsoon driven circulation, with basin-scaled cyclonic gyre in winter and anti-cyclonic gyre in summer. The intermediate layer circulation is opposite to the upper layer, showing anti-cyclonic gyre in winter but cyclonic gyre in summer. The circulation in the deep layer is much weaker in spring and summer, with the maximum velocity speed below 0.6 cm/s. In fall and winter, the SCS deep layer circulation shows strong east boundary current along the west coast of Philippine with the velocity speed at 1.5 m/s, which flows southward in fall and northward in winter. The results have also revealed a fourlayer vertical structure of water exchange through the Luzon Strait. The dynamics of the intermediate and deep circulation are attributed to the monsoon driving and the Luzon Strait transport forcing. 相似文献
4.
We propose an improvement of the algorithm of joint assimilation of the data on climatic temperature, salinity, and altimetric
sea level in a model of circulation. Unlike the previous works, the variances of the forecast errors of temperature and salinity
and the cross-covariance functions of of the forecast errors of salinity-level and temperature-level depend on the dynamics
of waters. It is shown that the structure of the fields of cross-covariance functions in the upper mixed layer is formed by
the vertical turbulent diffusion of the variances of forecast errors of temperature and salinity. At greater depths, these
statistical characteristics are mainly determined by the vertical advection. We compared the results of calculations with
and without taking into account the dynamics of the statistical characteristics. The analysis of the influence of the dynamics
of these characteristics makes it possible to reconstruct the mutually adapted climatic fields of temperature, salinity, and
horizontal and vertical current velocities in the Black Sea with the assimilation of data in the numerical model in each time
step.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 18–31, July–August, 2008. 相似文献
5.
V. V. Knysh G. K. Korotaev S. G. Demyshev V. N. Belokopytov 《Physical Oceanography》2005,15(3):142-160
We compare the thermohaline and dynamic characteristics of the Black Sea reconstructed by using two versions of climatic temperature
and salinity fields:old (1903–1982)and new (1903–2003). The fields are reconstructed with the help of continuous assimilation
of the climatic temperature and salinity in the model. It is shown that the climatic thermohaline fields constructed with
regard for the data of observations for the last 20 yr are characterized by an insignificant elevation of the halocline (pycnocline)in
the winter-spring period and the elevation of the upper boundary of the cold intermediate layer in the spring-summer period.
The intensity of surface geostrophic currents is greater than the same quantity computed on the basis of the old climatic
data for the whole year. The horizontal currents in the sea computed according to the new climatic data are more intense.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 11–30, May–June, 2005. 相似文献
6.
Yu. I. Sorokin 《Oceanology》2011,51(6):969-977
The rate of the hydrogen sulfide oxidation in the redox zone of the Black Sea and the rate of the hydrogen sulfide formation
due to bacterial sulfate reduction in the upper layer of the anaerobic waters were measured during the period of February–April
1991. The measurements were made using a sulfur radioisotope under conditions close to those in situ. It was established that
the hydrogen sulfide is oxidized in the layer where oxygen and hydrogen sulfide coexist, which is under the upper boundary
of the hydrogen sulfide layer. The maximum rate of the hydrogen sulfide oxidation was recorded within the limits of the density
values δτ of 16.20–16.30, while varying in the layer from 2 to 4.5 μM/day. The average rate of the hydrogen sulfide oxidation
was 1.5–3 times higher than that during the warm season. Sulfide formation was not observed at most of the stations in the
examined lower portion of the pycnocline layer (140 to 400 m depths). Noticeable sulfate reduction was detected only at one
station on the northwestern shelf. A probable reason for such noticeable changes in the sulfur dynamics in the water mass
of the Black Sea may be the intensified hydrodynamics in the upper layers of the water mass during the cold season. The data
suggesting that hydrogen sulfide oxidation proceeds under the hydrogen sulfide boundary indicate the absence of the so called
“suboxic zone” in this basin. 相似文献
7.
8.
Air-Sea Interaction, Coastal Circulation and Primary Production in the Eastern Arabian Sea: A Review
Air-sea interaction, coastal circulation and primary production exhibit an annual cycle in the eastern Arabian Sea (AS). During
June to September, strong southwesterly winds (4∼9 m s−1) promote sea surface cooling through surface heat loss and vertical mixing in the central AS and force the West India Coastal
Current equatorward. Positive wind stress curl induced by the Findlater jet facilitates Ekman pumping in the northern AS,
and equatorward-directed alongshore wind stress induces upwelling which lowers sea surface temperature by about 2.5°C (compared
to the offshore value) along the southwestern shelf of India and enhances phytoplankton concentration by more than 70% as
compared to that in the central AS. During winter monsoon, from November to March, dry and weak northeasterly winds (2–6 m
s−1) from the Indo-China continent enhance convective cooling of the upper ocean and deepen the mixed layer by more than 80 m,
thereby increasing the vertical flux of nutrients in the photic layer which promotes wintertime phytoplankton blooms in the
northern AS. The primary production rate integrated for photic layer and surface chlorophyll-a estimated from the Coastal
Zone Color Scanner, both averaged for the entire western India shelf, increases from winter to summer monsoon from 24 to 70
g C m−2month and from 9 to 24 mg m−2, respectively. Remotely-forced coastal Kelvin waves from the Bay of Bengal propagate into the coastal AS, which modulate
circulation pattern along the western India shelf; these Kelvin waves in turn radiate Rossby waves which reverse the circulation
in the Lakshadweep Sea semiannually. This review leads us to the conclusion that seasonal monsoon forcing and remotely forced
waves modulate the circulation and primary production in the eastern AS.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Seok Lee Heung-Jae Lie Cheol-Ho Cho Sok Kuh Kang William J. Teague Kyung-Il Chang Kyu-Min Song Kyung-Hee Oh 《Ocean Science Journal》2011,46(2):73-84
The vertical structure of the M2 tidal current in the Yellow Sea is analyzed from data acquired using an acoustic Doppler current profiler. The observed vertical
profiles of the M2 tidal current are decomposed into two rotating components of counter-clockwise and clockwise, and restructured using a simple
one-point model with a constant vertical eddy viscosity. The analyzed results show that the internal fictional effect dominates
the vertical structure of the tidal current in the bottom boundary layer. In the Yellow Sea, the effect of the bottom friction
reduces the current speed by about 20–40% and induces the bottom phase advance by about 15–50 minutes. In the shallower coastal
regions, the effects of bottom topography are more prominent on the vertical structure of tidal currents. The vertical profile
of the tidal current in summer, when the water column is strongly stratified, is disturbed near the pycnocline layer. The
stratification significantly influences the vertical shear and distinct seasonal variation of the tidal current. 相似文献
10.
11.
We propose an algorithm of adaptive statistics of prognostic errors aimed at the assimilation of the climatic temperature
and salinity fields in a model of dynamics of the sea. The algorithm is used for the numerical solution of the proposed differential
equations for the dispersions of prognostic errors of temperature and salinity. The sources in the equations of advective
diffusion of heat and salt depend on the four-dimensional dispersions of prognostic errors and one-dimensional (along the
vertical coordinate) dispersions of measurement errors. The dispersions of prognostic errors are corrected at the times of
assimilation of the data. We perform the reconstruction and analysis of the climatic fields of currents in the Black Sea.
It is shown that the structure of the fields of dispersions in the upper mixed layer is determined by the vertical diffusion.
Below this layer, the distribution of dispersions depends on the vertical advection. The algorithm of adaptive statistics
of prognostic errors allows us to reconstruct the improved mutually adapted hydrophysical parameters with regard for the dynamics
of the dispersions of errors.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 26–37, January–February, 2008. 相似文献
12.
We present the results of analysis of the advection mechanism of replenishment and refreshment of the cold intermediate layer in the Black Sea. The analysis is based on the investigation of the fields of temperature, salinity, density, currents, and the coefficient of vertical turbulent diffusion obtained in the course of prognostic calculations according to the three-dimensional complete model with seasonally variable external fields in boundary conditions. It is discovered that, parallel with winter convection, the cold intermediate layer in the central part of the sea is also replenished and refreshed as a result of the transportation of cold waters formed in the northwest part of the sea by currents.__________Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 17–30, November–December, 2004. 相似文献
13.
In the southwestern Okhotsk Sea off Hokkaido we observed chemical components related to the carbonate system for 1 year from
August 1997 to June 1998. Using the conservative components salinity and water temperature, we confirmed the existence of
two water masses flowing into the intermediate layer of the Okhotsk Sea, the East Sakhalin Current Water (ESCW) which becomes
denser by mixing of brine water, and the Forerunner of Soya Warm Current Water (FSWW) which becomes denser due to cooling
of the saline Kuroshio water. The ΔNTCx values were calculated by comparing the ESCW and the FSWW with the Pacific Deep Water (PDW). The ΔNTCx values obtained are 100–110 μmol/kg and 70–100 μmol/kg for the ESCW and the FSWW off Hokkaido, respectively, which are considerably
larger than that of the Kuroshio water. These large ΔNTCx values may be due to both low DIC concentration in the surface water and intense gas exchange under the cold and stormy winter
conditions for the ESCW and the cooling of the FSWW as it flows northward. Since the flow rates of dense waters concerned
with the ESCW and the FSWW have previously been estimated as 0.9 Sv and 0.2 Sv, respectively, the amount of atmospheric CO2 absorbed and transported to the intermediate layer turns out to be 3.9−4.1 × 1013 gC/yr. This flux is small on a global scale, but the flux divided by the surface layer of the Okhotsk Sea is 30 gC/m2/yr, which is 5 times greater than the mean absorption flux of anthropogenic CO2 in the world's oceans. It is thus considered that atmospheric CO2 is efficiently absorbed in the Okhotsk Sea.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
To describe the phenomenon of cold surges in the Black Sea in winter, we study the problem of atmospheric response to a local
heat source on the surface in two simple formulations. In the shallow-water model, the planetary boundary layer of the atmosphere
is homogeneous with variable upper bound. In the second model, the boundary layer has a constant thickness and its stratification
is homogeneous. In the one-dimensional problem, for a constant wind blowing perpendicularly to the sea coast, the atmospheric
response is determined by a single dimensionless parameter called the Froude number. Depending on its value, there are two
possible different modes of the response. The range Fr < 1 (subcritical mode) corresponds to gentle winds, strong stratifications,
thick boundary layers, and high velocities of inertial gravitational waves. The range Fr > 1 (supercritical mode) corresponds
to strong winds, weak stratifications, thin boundary layers, and low wave velocities. In the two-dimensional problem for a
round sea, there are four qualitatively different types of response depending on the combination of two dimensionless parameters:
the Froude number and the ratio of the radius of the sea to the radius of deformation.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 3–22, September–October, 2008. 相似文献
15.
V. M. Kushnir E. Hansen L. A. Petrenko V. K. Pavlov A. N. Morozov S. V. Stanichnyi S. V. Fedorov 《Physical Oceanography》2007,17(5):278-295
The numerical analysis of the stationary field of current velocity on the upper boundary of the bottom boundary layer in the
Barents Sea is performed on the basis of a simplified model taking into account the fields of wind velocity and density of
water for the principal periods of the seasonal cycle and the bottom topography. The analysis is based on the climatic BarKode database and the data on the wind velocity over the Barents Sea for the last 50 yr. The numerical results demonstrate that
the field of bottom currents is fairly nonuniform and the current velocities vary from several fractions of 1 cm/sec to 5
cm/sec in the zones with noticeable slopes of the bottom. The estimates of the thickness of the bottom boundary layer are
obtained for the constant coefficient of bottom friction C
f
= 0.04. In the major part of the water area of the Barents Sea, the thickness of the bottom boundary layer is close to 1
m. In the regions with significant slopes of the bottom, it increases to 2–2.5 m and, in the two zones of intensification
of the bottom currents, becomes as large as 5 m. The maximum estimate of the coefficient of turbulent viscosity is close to
5 cm2/sec. The mean value of the coefficient of vertical density diffusion K
S
is equal to 2.34 cm2/sec and its standard deviation is equal to 1.52 cm2/sec.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 31–49, September–October, 2007. 相似文献
16.
The long-wave outgoing radiation, effective cloudiness equal to the product of the total cloud amount by their optical density,
and the sea-surface temperature determined from the satellites are used to determine the annual course of the components of
external heat balance on the sea surface whose climatic anomalies, parallel with the meridional heat and water transfer in
the ocean-atmosphere system, specify the intraannual and interannual large-scale variations of weather in different regions
of the Earth. The development of these studies is connected with the progress of satellite hydrophysics because the data obtained
from the space become sufficiently exact, regular, and global. The increase in the existing data array on the external heat
balance of the oceans from ∼15–20 to 100 yr and more would promote the solution of the problem of oscillations of Earth's
climate. We present examples of coordinated numerical analysis of the heat balance of the upper (0–100 m ) layer of the Black
Sea performed on the basis of the shipborne and satellite data.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 59–75, November–December, 2007. 相似文献
17.
V. A. Dulov V. N. Kudryavtsev V. I. Shrira V. E. Smolov A. N. Bol’shakov 《Physical Oceanography》2007,17(1):29-40
We describe the procedure of field experiments aimed at measuring the vertical profiles of the vectors of a drift current
with the help of quasi-Lagrangian drifters. We present the data on the vertical shears of the current at depths of 0.5–5 m
obtained under the conditions of neutral stratification in the upper 5-m layer of the sea in the presence of weak and moderate
winds. The correspondence of the obtained data to the concept according to which the subsurface layer of the sea is regarded
as a near-wall turbulent layer with Ekman current located below is analyzed. A conclusion is made that the results of measurements
correspond, on the average, to the classical concepts demonstrating both the region of logarithmic sublayer and its transition
into the Ekman spiral.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 32–44, January–February, 2007. 相似文献
18.
V. A. Blinkov 《Physical Oceanography》1999,10(2):183-192
We describe the characteristics of a towed complex used for measurements in the upper layer of the ocean under the conditions
of periodic deepening and lifting (scanning) of a carrier with sensors connected with the ship by a weight-carrying cable
of constant lengt. For a maximum scanning range of 0–200 m and a towing speed of up to 12 knots, the measurements were performed
every 1.5–2.0 km. The minimum vertical scale of recorded temperature and conductivity inhomogeneities is 0.05–0.08 m. We present
the results of measurements carried out by the towed complex in a section of the frontal zone in the north-east part of the
Tropical Atlantic.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
19.
Characteristics of variations of water properties and density structure around the Kuroshio in the East China Sea 总被引：5，自引：0，他引：5
Quarterly data of CTD at the PN line in the East China Sea during 1988–94 were analyzed to examine the variations of water
properties and density structure in relation to the Kuroshio. The Kuroshio flows over the continental slope at the PN line.
Water properties in the surface layer less than 100 db change greatly and show a clear seasonal cycle, while those in the
subsurface layer are much less variable. The small isobaric variations in the subsurface layer are almost due to the vertical
movement of isopycnals, on which the water properties vary little. The subsurface variations of salinity, temperature and
isopycnal depth are classified into four groups occurring in the four regions, divided vertically by the middle of the main
pycnocline and horizontally by the offshore edge of the Kuroshio, named Groups 1 (upper Kuroshio), 2 (upper offshore region),
3 (lower Kuroshio), and 4 (lower offshore region). The difference in averaged isopycnal depth between Groups 1 and 2 (3 and
4) is highly correlated with the vertical shear of the Kuroshio velocity in the upper (lower) pycnocline. The isopycnal depth
of Groups 1 and 3 has little annual cycle (with large intraseasonal variations in Group 3), while that of Groups 2 and 4 shows
a clear seasonal variation with the minimum in fall. As a result, the Kuroshio velocity is smallest in fall almost every year,
although the amplitude of seasonal variation and the season of maximum velocity are different from year to year. Interannual
variations of isopycnal depth are characterized by a large amplitude of Group 2 and an opposite phase between Groups 3 and
4, so that the variations of difference in isopycnal depth between Groups 1 and 2 and Groups 3 and 4, i.e., the upper and
lower shear of the Kuroshio velocity, are comparably significant. 相似文献
20.
A. S. Samodurov V. Z. Dykman V. A. Barabash O. I. Efremov A. G. Zubov O. I. Pavlenko A. M. Chukharev 《Physical Oceanography》2005,15(5):311-322
We describe a new measuring complex aimed at the investigation of small-scale processes in the upper active layer of the sea.
The necessity of creation of a complex of this sort is justified and a circle of problems that can be solved with the help
of this complex is described. The scales of resolution of horizontal and vertical inhomogeneities in measuring in the mode
of vertical probing are theoretically estimated. The basic technical characteristics of the complex are presented. We also
present the results of laboratory and field tests, which confirm the agreement between the calculated and actual technical
possibilities of the complex. The structural features of various versions of the “Sigma-1” measuring complex (the “Sigma-1P”
point-to-point-operation version and the “Sigma-1Z” probing version) are described.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 60–71, September–October, 2005. 相似文献