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1.
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
2.
We provide an expert quality assessment of the data for 1932–1993 and used these data to perform the numerical analysis of
the carbonate system of the aerobic zone in the Black Sea. The intraannual and long-term variations of the carbonate system
are studied in the abyssal part of the sea for 1960–1993. We propose explanations of the intraannual variations of the analyzed
system for various layers of the aerobic zone and reveal long-term variations of the pH values, total alkalinity, and the
ratios of the components of the carbonate system. We discover and explain the observed increase in the concentrations of TCO2 and CO2 and the partial pressure of carbon dioxide pCO2, as well as a decrease in pH values and the concentration of CO32− in waters of the aerobic zone of the Black Sea. 相似文献
3.
S. I. Pogosyan A. M. Durgaryan I. V. Konyukhov O. B. Chivkunova M. N. Merzlyak 《Oceanology》2009,49(6):866-871
A device for integrating cavity absorption measurements (ICAM) with an internal diameter of 80 mm suitable for field research
is described. The spectral features of the light absorption by some cyanobacteria, green algae, and diatoms in the integrating
sphere were studied and the dependences of the absorption on the cell concentration were determined in comparison with the
conventional measurements in a 1-cm cuvette. The sensitivity of the chlorophyll estimation with the ICAM reached 0.2–0.5 mg
m−3. The results of the ICAM application for the direct analysis of the natural phytoplankton and dissolved organic (“yellow“)
matter in the Black Sea and the Sea of Japan are described. 相似文献
4.
The paper discusses the results of numerical experiments on response of the Black Sea to the ‘real’ (mean monthly) atmospheric
forcing. A new version of the multi-layer quasi-isopycnic model is applied which does not use the rigid-lid approximation
and allows for a salt flux through the sea surface. Ways of obtaining quantitative agreement between the calculated data due
only to the external forcing, without invokingin situ temperature/salinity observations are suggested.
Translated by Vladimir A. Puchkin. 相似文献
5.
The data of meteorological and oceanographic observations on the northwest shelf of the Black Sea for 1973–2000 are used to
compute the characteristics of the entire area in the presence of hypoxia of waters under the pycnocline in the summer–autumn
period and the area of surface waters with a level of salinity lower than 17.5‰ in May. The time of onset of the spring warming
of air (stable transition through a temperature of 5°) is determined. A statistically significant positive trend of the air
temperature (0.8° per 100 yr) is revealed in Odessa. The process of warming was observed mainly for the winter (1.5° per 100
yr) and spring (0.8° per 100 yr) periods and became especially intense since the beginning of the 1990s. On the basis of the
data of correlation analyses, we establish a statistically significant relationship between the large-scale atmospheric processes
[the index of North Atlantic Oscillation (NAO) and the wind conditions], the area of surface waters whose salinity is lower
than 17.5‰, and the total area with hypoxia in the summer–autumn periods. For positive mean values of the NAO index (in January–March),
we most often observe early spring with elevated repetition of the south and west winds with subsequent development of hypoxia
in large areas of the northwest shelf. We propose an empirical regression model for the prediction of the total area of summer–autumn
hypoxia of waters with predictors: the onset of the spring warming of air and the area of propagation of waters whose salinity
is lower than 17.5‰ in May. The maximum error of prediction of the area with hypoxia does not exceed 5.5 ⋅ 103 km2, i.e., less than 2% of the total area of the northwest shelf in the Black Sea (to the north of 45°N). 相似文献
6.
In May 2007, the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences carried out an oceanographic
expedition in the northwest sector of the Black Sea. This expedition originates a series of surveys scheduled for this region.
It was realized within the framework of national and international projects, such as Climate, Ecoshelf, Stable Ecosystem, SESAM, ECOOP, and Oceanography. We present the data on the works carried out in this expedition and perform a brief analysis of the process of subduction
of waters on the northwest shelf. It is shown that, despite the abnormally warm preceding autumn–winter period, the wellpronounced
subduction of waters formed in the process of autumn–winter cooling was still observed over the drop of depth along the isopycnic
surfaces σt = 14.0 and σt = 14.5–14.6 in May 2007. New data on the intensity of vertical turbulent exchange over the continental slope in the northwest
part of the Black Sea are obtained. 相似文献
7.
For the Black-Sea region, we perform the dynamic reanalysis of the data on atmospheric circulation for the period 1958–2001
by using the HadRM3P model with a space resolution of 25 km. We estimate the mean climatic atmospheric fields of vorticity and divergence of the
wind velocity and study their space structure and seasonal variability. The climatic estimates of the annual course of vorticity
of the wind velocity over the sea are presented. The obtained large annual average values of vorticity of the velocity reveal
the predominant role played by the wind action in the generation not only of the seasonal variability but also of the mean
cyclonic circulation of waters in the Black Sea. 相似文献
8.
G. S. Karabashev 《Oceanology》2011,51(1):36-38
Based on the comparative analysis of the characteristics of the early summer maxima of the normalized radiance from the satellite
ocean color data, the seasonal trend of the concentration of the chlorophyll “a,” and the species composition of the phytoplankton
from determinations in water samples from the Black Sea, it is concluded that the summer chlorophyll maximum is due to the
coccolithophorid bloom occurring from late May to mid June in the Black Sea basin. 相似文献
9.
O. A. Yunev 《Oceanology》2011,51(4):616-625
Using the data of daily primary production, as well as intraannual and long-term changes in the concentration of chlorophyll
“a” and hydrochemical characteristics, the annual primary production of phytoplankton in the deep-water part of the Black
Sea is estimated for the three key periods in the contemporary evolution of the sea: preeutrophication, very intense eutrophication,
and the present-day period characterized by deeutrophication. It is shown that eutrophication in the second part of the 20th
Century led to an increase in the production level not only in the shelf of the Black Sea, but also its deep-water areas.
By the end of the 1980s and the early 1990s, the value of the annual primary production in this part of the sea increased
from 63 ± 18 g C m−2 yr−1 (in the 1960s) up to 135 ± 30 g C m−2 yr−1. On the contrary, after 1993, mainly because of reduced runoff of biogenic substances into the Black Sea from land based
sources, there was a decrease in the annual production of phytoplankton in the deep-water areas of the sea, which is currently
about 105 g C m−2 yr−1. 相似文献
10.
On the basis of the data of field measurements, we present the results of numerical analysis of the intensity of vertical
turbulent exchange in stratified layers of the Black Sea in the region of the shelf–continental-slope boundary depending on
the local stratification. The experiments were carried out within the framework of the GEF/BSERP and Black Sea-2004 international projects. The data were obtained by using a probing version of the Sigma-1 measuring complex. In processing the data of measurements, we apply a procedure of evaluation of the coefficient of vertical
turbulent diffusion depending on the external conditions based on the analysis of the spectra of the gradient of temperature
fluctuations. For the two studied regions of the shelf, the coefficients of turbulent exchange turn out to be much higher
(by about an order of magnitude) than for the open sea under similar conditions. This can be explained by the specific features
of the bottom topography affecting the dynamics of quasiinertial waves playing to role of the main causes of small-scale mixing
and vertical diffusion.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 14–24, November–December, 2008. 相似文献
11.
We demonstrate the possibility of determination of the spectral characteristics of absorption and backward scattering of light
in the Black Sea according to the data of a SeaWiFS satellite device. We use specially selected data of observations obtained under favorable atmospheric conditions. It is shown
that the results of calculations performed by using different methods are almost identical and weakly depend on the model
parameters of the spectral course of the coefficients of absorption of light by yellow substance and its scattering by suspended
particles. 相似文献
12.
We demonstrate the importance of investigation of the behavior of methane as a source of energy and an element of the Black-Sea
ecosystem affecting the global behavior of the climate. We describe the genesis of methane and the processes of its aerobic
and anaerobic oxidation. An especially important biogeochemical and ecological role is played by the anaerobic oxidation of
methane guaranteeing the formation of its effective sink inside the anaerobic zone and preventing its penetration into the
atmosphere as a greenhouse gas. On the basis of the analysis of the experimental data available from the literature, we also
discuss the principal regularities of the distribution of concentration of methane and its flows. It is shown that the formation
of methane hydrates at the bottom in the abyssal part of the Black Sea and the events of jet gas release on the periphery
of the basin can be regarded as the components of a single global process of gas release from the bottom of the Black Sea.
We present estimates of the components of methane budget in the Black Sea. The results of simulation of the dynamics of methane
bubbles and the processes of their gas exchange with the medium are analyzed. The data of hydroacoustic measurements are used
to evaluate the distribution of methane bubbles in sizes and the mass transfer of methane through the ocean–atmosphere interface.
Finally, we consider the methods of mathematical simulation of the distribution of methane in the ecosystem of the Black Sea.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 40–56, September–October, 2008. 相似文献
13.
V. A. Ivanov V. A. Naumova V. V. Fomin L. V. Cherkesov T. Ya. Shul’ga 《Physical Oceanography》2008,18(6):332-344
The prognostic fields of the surface winds and atmospheric pressure obtained according to the data of the Skiron prognostic system are used to study the surge phenomena in the Azov Sea by using a three-dimensional nonlinear model. The
accumulated numerical results are compared with the data of direct measurements of the sea level at the coastal stations.
The degree of sensitivity of the computed levels of surges to the value of the coefficient of surface friction is evaluated.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 53–65, November–December, 2008. 相似文献
14.
The South China Sea(SCS) and the Arabian Sea(AS) are both located roughly in the north tropical zone with a range of similar latitude(0°–24°N). Monsoon winds play similar roles in the upper oceanic circulations of the both seas. But the distinct patterns of chlorophyll a(Chl a) concentration are observed between the SCS and the AS.The Chl a concentration in the SCS is generally lower than that in the AS in summer(June–August); the summer Chl a concentration in the AS shows stronger interannual variation, compared with that in the SCS; Moderate resolution imaging spectroradiometer(MODIS)-derived data present higher atmospheric aerosol deposition and stronger wind speed in the AS. And it has also been found that good correlations exist between the index of the dust precipitation indicated by aerosol optical thickness(AOT) and the Chl a concentration, or between wind and Chl a concentration. These imply that the wind and the dust precipitation bring more nutrients into the AS from the sky, the sub-layer or coast regions, inducing higher Chl a concentration. The results indicate that the wind velocity and the dust precipitation can play important roles in the Chl a concentration for the AS and the SCS in summer. However aerosol impact is weak on the biological productivity in the west SCS and wind-induced upwelling is the main source. 相似文献
15.
S. G. Demyshev 《Physical Oceanography》2010,20(3):184-195
Within the framework of the Mellor–Yamada approach, we realize a numerical scheme for the calculation of the coefficients
of turbulent viscosity and diffusion in the z -system of coordinates for the three-dimensional model of operative prediction of currents in the Black Sea. Some discrete
analogs of the equations for turbulent kinetic energy and turbulence macroscale are studied. Their high sensitivity to the
choice of finite-difference approximations is demonstrated. On the basis of the comparison of the results of prognostic experiments
with the data of observations, we choose the best approximation of the term used to describe the generation pf turbulence
energy. 相似文献
16.
The effects of a week-long exposure to copper sulfate (0.05–5000 mg/l) and cadmium chloride (2 and 10 mg/l) upon the morpho-functional
characteristics of the Black Sea bivalve mollusks Anadara cf. inaequivalvis and Chamelea gallina were studied. The changes in the morpho-functional state of mollusks at the impact of these metals are distinguished. These
changes included a 60% decrease in the hemocytes’ concentration in the hemolymph and a 5- to 7-fold decline of the hemocyte
adenosine triphosphate (ATP) content, along with the appearance in the mollusks of “brown” cells and lipofuscin-like pigment.
The exposure to both metals caused similar changes. 相似文献
17.
E.V. Stanev J. Staneva J.L. Bullister J.W. Murray 《Deep Sea Research Part I: Oceanographic Research Papers》2004,51(12):2137-2169
Data from field observations and numerical model simulations are used to understand and quantify the pathways by which passive tracers penetrate into the Black Sea intermediate and deep layers. Chlorofluorocarbon (CFC) concentrations measured during the1988 R.V. Knorr cruise show strong decrease with increasing density in the Black Sea and illustrate the very slow rate of ventilation of deep water in this basin. We develop a 3D numerical model based on the Modular Ocean Model (MOM), and calibrate it in a way to produce consistent simulations of observed temperature, salinity and CFCs. One important feature is the implementation of a special parameterization for convection, which is an alternative of the convective adjustment in MOM and handles the penetration of the Bosporus plume into the halocline. The model forcing includes interannually variable wind, heat and water fluxes constructed from Comprehensive Ocean–Atmosphere Data Set and ECMWF atmospheric analysis data and river runoff data. The analysis of observations and simulated data are focused on correlations between thermohaline and tracer fields, dynamic control of ventilation, and the relative contributions of sources at the sea surface and outflow from the Bosporus Strait in the formation of intermediate and deep waters. A simple theory is developed which incorporates the outflow from the strait along with the vertical circulation (vertical turbulent mixing and Ekman upwelling) and reveals their mutual adjustment. The analyses of simulated and observed CFCs demonstrate that most of the CFC penetrating the deep layers has its source at the sea surface within the Black Sea rather than from the Marmara Sea via the Bosporus undercurrent. Under present-day conditions, the surface CFC signals have reached only the upper halocline. Intrusions below 600 m are not simulated. The major pathways of penetration of CFCs are associated with cold-water mass formation sites, Bosporus effluent, as well as with the diapycnal mixing in the area of Rim Current. Future CFC sampling strategies coherent with the unique conditions in the Black Sea are discussed. 相似文献
18.
S. A. Mosharov 《Oceanology》2010,50(6):884-892
The studies were performed from September 10 to 29 of 2007 in the Kara Sea in transects westward of the Yamal Peninsula, near
the St. Anna Trough, in the Ob River’s estuary, and on the adjacent shelf. The concentration of chlorophyll a in the euphotic layer changed from 0.02 to 4.37 mg/m3, amounting on the average to 0.76 mg/m3. The primary production in the water column varied from 10.9 to 148.0 mg C/m2 per day (the mean was 56.9 mg C/m2 per day). It was shown that frontal zones divided the Kara Sea into distinct areas with different productivities. The maximum
levels of the primary production were measured in the deep part of the Yamal transect (132.4 mg C/m2 per day) and the shallow Kara Sea shelf near the Ob River’s estuary (74.9 mg C/m2 per day). The characteristics of these regions were the low salinity of the surface water layer (19–25 psu) and the elevated
silicon content (12.8–28.1 μg-atom Si/l), which is explainable by the river water inflow. The frontal zones of the Yamal Current
in the Yamal and Ob transects displayed high values of the assimilation numbers, amounting to 2.32 and 1.49 mg C/mg of chlorophyll
per h, respectively (the maximal for the studied regions). 相似文献
19.
The spatial distribution of the primary production (PP) and the chlorophyll a concentration (Chl) were investigated during two research cruises in the Drake Passage area in October–November of 2007 and
2008. The algorithm evaluating the integral PP (PPint) for the water column in this area was developed based on the data on the surface chlorophyll (Chls) and the incident solar irradiance obtained in 2004–2008 in the Atlantic Sector of the Southern Ocean. The results obtained
both by the experimental and model approaches suggested that the Polar Front (PF) region of the Drake Passage was characterized
by low values of both the PPint (<100 mg C/m2 per day) and Chls (0.08–0.20 mg/m3) in October–November. Low values of the Chls and relatively high phaeophytine a concentrations indicated the winter succession state of the phytoplankton community in the Antarctic Ocean and the southern
Polar Frontal Zone (PFZ). The seasonal warming of the surface water layers and the developing pycnocline resulted in a phytoplankton
bloom and a Chls concentration of more than 1 mg/m3 in mid-November in this area and the Subantarctic waters. 相似文献
20.
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