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1.
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
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.
A numerical model of baroclinic circulation based on the use of a double sigma coordinate system is presented and its application
to the simulation of flows and temperature and salinity fields in the Dnieper-Bug Estuary is described. The model reproduces
the salinity and temperature fields surveyed in 1998. The results of simulations reveal the existence of a global influence
of the relatively narrow and deep ship channel (through which Black-Sea waters can penetrate deep into the estuary) on the
transport processes.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 66–77, November–December, 2008. 相似文献
4.
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
5.
Ryabinin A. I. Mal'chenko Yu. A. Saltykova L. V. Bobrova S. A. Zhuk L. I. 《Physical Oceanography》2003,13(5):284-298
We present the data on the mean values of concentrations and the ranges of their variation for 27 microelements in the Black-Sea waters near the South Coast of the Crimea in 1991–2000, analyze the main types of variability exhibited by the concentrations of microelements in this period, and establish the relationship between the concentrations of some microelements and the variations of salinity of seawater. 相似文献
6.
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
7.
We analyze the seasonal variability of the climatic hydrophysical fields of the Black Sea reporduced in three numerical experiments
carried out according to the model of circulation. The numerical predictions are performed for a period of 12.5 yr on the
basis of the hydrological data accumulated in 1983–1995. The monthly average climatic fields of the current speed are reconstructed
according to the data on the climatic fields of temperature and salinity by the method of hydrodynamic adaptation (standard).
It is shown that, in prognostic calculations, the seasonal variability of temperature and salinity is qualitatively close
to the “standard” dependence. At the same time, the quantitative difference between the climatic behavior of the model and
the standard dependence may be significant. The annual cycle of the currents is characterized by the intensification of the
Main Black-Sea Current in winter. The structure of the hydrophysical fields of the sea in the model becomes much more realistic
if it is based on the actual hydrological data.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
8.
On the basis of processing of the oceanographic data accumulated for the water area of the North Atlantic in 1950–1999 (∼500,000
stations), we study seasonal and interannual variations of the principal characteristics of pycnocline within the range of
σt = 25.5–27.5 conventional density units. It is shown that the interannual oscillations of these characteristics in the entire
analyzed layer can be regarded as a superposition of fluctuations with periods from 2–3 to 10–12 yr. The typical ranges of
these fluctuations for the depths of occurrence of isopycnic surfaces and the corresponding temperature and salinity are equal
to 20–25 m, 1–1.5°C, and 0.25‰, respectively. The intensification of atmospheric circulation at middle latitudes is accompanied
by the simultaneous deepening of the pycnocline and its heating in the central part of the North Subtropical Anticyclonic
Gyre. At the same time, the process of weakening of the atmospheric circulation leads to the rise of the pycnocline and its
cooling. The complete cycle of interaction of the North-Atlantic Oscillation with the anomalies of isopycnic characteristics
(with regard for the period of their advection) is equal to ∼6–8 yr.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 29–48, March–April, 2007. 相似文献
9.
A. A. Sizov 《Physical Oceanography》2001,11(3):259-270
We study the interannual and seasonal variability of hydrometeorological fields in some regions of the Atlantic-European sector.
These low-frequency processes are analyzed depending on the index ΔP (an analog of the index of the North-Atlantic Oscillation). It is shown that the average value of the index ΔP over the winter natural synoptic season can be used for the determination of stable locations of the centre of the Azorean
maximum in 1971–1980 and 1981–1990, the typical state of cloudiness in the Atlantic-European sector, and the fields of precipitations
and atmospheric temperature in some regions of the Crimea. Typical anomalies of the fields of precipitations and atmospheric
temperature over the west and south coasts of the Crimea are described. The signs of the anomalies of precipitations in the
winter natural synoptic season are in good agreement with the signs of the corresponding anomalies of the field of cloudiness
in the Black-Sea region.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
10.
We study model climatic temperature and salinity fields and the fields of currents in the 350–1000-m layer. The following
specific features are revealed: Colder waters are observed in the regions with anticyclonic vorticity. At the same time, warmer
waters are detected in the regions with cyclonic vorticity. This temperature effect can be explained by the elevation of temperature
with depth below the main pycnocline. In the region of the Sevastopol anticyclone, at depths greater than 500 m, we observe
a zone of cyclonic rotation of waters. Near the Caucasian coast, in the region of Gelendzhik, we reveal a narrow jet current
existing at a depth of 350 m from March till July.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp.3–15, January–February, 2009. 相似文献
11.
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
12.
As applied to the transparency meter installed in the hydrometeorological complex aimed at monitoring the Black-Sea coastal
waters, we show the possibility of evaluation of various characteristics of state of the marine medium according to the data
of measurements of the beam attenuation coefficient in two spectral regions: short-and long-wave. For this purpose, we use
biooptical relations established on the basis of the experimental data accumulated for the Black Sea.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 37–45, March–April, 2008. 相似文献
13.
Seasonal and interannual variations in physicochemical properties were investigated in the neritic area of Sagami Bay, Kanagawa,
Japan, from December 2000 to December 2005. Physicochemical properties (i.e. temperature, salinity, density, dissolved oxygen
and dissolved inorganic nutrient concentration) revealed clear seasonal variations, which were similar to each other during
all 5 years. Temperature, salinity and dissolved inorganic nutrients showed rapid, drastic variations within a few days and/or
weeks. These variations are related to sea levels, principally due to the shifting effects of the Kuroshio Current axis: they
were strongly affected by the Kuroshio Water and other waters, when sea level difference was greater than ca. 35 cm and lower
than ca. 15 cm, respectively. Temperature difference (DF
T
) increased with sea level difference, and the difference of salinity and dissolved inorganic nutrients (NH4
+-N, NO3
−+NO2
−-N, NH4
++NO3
−+NO2
−-N, PO4
3−-P and SiO2-Si) increased and decreased with DF
T
, respectively. All these correlations are significant. Total dissolved inorganic nitrogen (N), phosphate (P) and silicate
(Si) revealed seasonal variations in the ranges of 0.57–16.08, 0.0070–0.91 and 0.22–46.38 μM, respectively. From the regression equations between these elements allowed the following relation to be obtained; Si:N:P
= 14.8:13.4:1. Dissolved inorganic nutrients were characterized by Si and/or P deficiency, especially in the upper layer (0–20
m depth) during summer. Single and/or combined elements are discussed on the basis of potential and stoichiometric nutrient
limitations, which could restrict phytoplankton (diatom) growth as a limiting factor. 相似文献
14.
We study the space and time variations of the concentration of chlorophyll in the Black-Sea coastal zone (near Katsiveli)
in summer 2001–2002. Typical vertical profiles of the pigments are presented. The relations between the concentration of chlorophyll
and the optical parameters of seawater (including the Secchi depth, sea reflectance, effective wavelength of the upwelling
radiation, and the vertical attenuation coefficient of light) are analyzed. The equations for the biological parameters of
seawater and its optical characteristics are presented.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 36–51, May–June, 2006. 相似文献
15.
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
16.
17.
Stephanie K. Moore Nathan J. Mantua Jan A. Newton Mitsuhiro Kawase Mark J. Warner Jonathan P. Kellogg 《Estuarine, Coastal and Shelf Science》2008,80(4):545-554
Temporal and spatial patterns of variability in Puget Sound's oceanographic properties are determined using continuous vertical profile data from two long-term monitoring programs; monthly observations at 16 stations from 1993 to 2002, and biannual observations at 40 stations from 1998 to 2003. Climatological monthly means of temperature, salinity, and density reveal strong seasonal patterns. Water temperatures are generally warmest (coolest) in September (February), with stations in shallow finger inlets away from mixing zones displaying the largest temperature ranges. Salinities and densities are strongly influenced by freshwater inflows from major rivers during winter and spring from precipitation and snowmelt, respectively, and variations are greatest in the surface waters and at stations closest to river mouths. Vertical density gradients are primarily determined by salinity variations in the surface layer, with stations closest to river mouths most frequently displaying the largest buoyancy frequencies at depths of approximately 4–6 m. Strong tidal stirring and reflux over sills at the entrance to Puget Sound generally removes vertical stratification. Mean summer and winter values of oceanographic properties reveal patterns of spatial connectivity in Puget Sound's three main basins; Whidbey Basin, Hood Canal, and Main Basin. Surface waters that are warmed in the summer are vertically mixed over the sill at Admiralty Inlet and advected at depth into Whidbey Basin and Hood Canal. Cooler and fresher surface waters cap these warmer waters during winter, producing temperature inversions. 相似文献
18.
The paper considers the thermohaline structure of Black Sea abyssal and near-bottom waters on the basis of exact measurements
recorded in recent years under the HYDROBLACK and COMSBLACK international projects. The surface water mass (along with the
cold mixed layer), the intermediate, abyssal, and near-bottom masses are identified. The upper boundary of deep waters is
defined as a depth level where the density ratio decreases down to 0.1 This depth roughly corresponds to the 900–1100 m depth
levels. Furthermore, the paper provides potential temperature and salinily values in the near-bottom layer, with an error
of, respectively, 0.002°C and 0.002‰, at most.
Translated by Vladimir A. Puchkin. 相似文献
19.
We study the regularities of annual variations in the concentration of oxygen and the degree of saturation of waters in the
Sevastopol Bay with oxygen in 1998–2009. The three-dimensional specific features of seasonal variations in the distribution
of oxygen in waters of the Sevastopol Bay are revealed. Two periods can be separated in the annual course of the content of
oxygen in the surface layers of waters in all parts of the bay: the period of supersaturation in March–September and the period
of undersaturation in October–February. In the bottom layer of waters in all parts of the bay, we observe the undersaturation
of waters with oxygen for the whole year. 相似文献
20.
L. D. Pukhtyar 《Physical Oceanography》2005,15(4):220-231
On the basis of the data from the databank of the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences
and the data of regional marine hydrometeorological stations, we present the characteristics of the seasonal variability of
temperature and salinity frontal zones and background gradients in waters of the Karkinitskii Bay. We determine the locations
of the frontal zones, the values of their gradients, horizontal scales, repetition, connection with weather conditions, inflow,
and direction of propagation of salt and freshened waters in the bay in different seasons of the year.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 30–42, July–August, 2005. 相似文献