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1.
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.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 11–30, May–June, 2005. 相似文献
2.
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
3.
V. V. Knysh S. G. Demyshev G. K. Korotaev A. S. Sarkisyan 《Izvestiya Atmospheric and Oceanic Physics》2007,43(3):363-377
A method for combined assimilation of climatic hydrologic fields of temperature, salinity, and the climatic dynamic level of the Black Sea into a model of sea dynamics is proposed. The monthly mean fields of the dynamic sea level were obtained from the results of assimilation of satellite altimetry data into the model. The statistical characteristics of errors in the forecasts of the level, salinity, and temperature were assumed to be proportional to the statistical characteristics of the differences between monthly mean climatic fields of temperature, salinity, and sea level calculated by means of assimilating altimetry observations of the sea level and analogous climatic hydrologic fields. The climatic fields of currents are reconstructed and analyzed. The assimilation of the climatic altimetry level allows the reproduction (in current fields) of quasi-stationary synoptic anticyclonic eddies located along the periphery of the Black Sea Rim Current. 相似文献
4.
Impact of the winter cooling on the variability of the thermohaline characteristics of the active layer in the Black Sea 总被引:1,自引:0,他引:1
The influence of the winter atmospheric forcing on the interannual variability of the Black Sea’s active layer’s thermohaline
structure during 1982–2008 is investigated. The results are based on the combined analysis of the hydrological measurements
from a ship, satellite measurements of the sea’s surface temperature (SST), and the NCEP/NCAR reanalysis data for the surface
air temperature (SAT). A high correlation between the variability of the winter mean SST/SAT and the thermohaline characteristics
of the active layer during the following warm season was found. It is shown that the winter atmospheric forcing significantly
affects the variability of the temperature, salinity, and density down to the 150–200 m depth, and this has to be considered
in the analysis of the interannual and long-term variability of the Black Sea’s active layer. 相似文献
5.
The climatic features of the formation of precipitation and their correlation with the baric situation in the Atlantic-European
sector are studied on the basis of the data of the Sevastopol and Feodosiya coastal hydrometeorological stations. As the source
data, we use the data arrays of daily precipitation at these stations in 1900–2005 and the data of reanalysis of the fields
of atmospheric pressure in the Atlantic-European sector. The comparative statistical analysis of daily precipitation for the
wet and dry summer and winter seasons and the estimates of extremely high levels of precipitation for the specified periods
of repeatability are presented. The existence of the dependence of occurrence of wet and dry winter seasons in Sevastopol
and Feodosiya on the large-scale baric fields in the Atlantic-European sector is confirmed.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 43–51, July–August, 2008. 相似文献
6.
In order to reconstruct the large-scale temperature and salinity fields by the method of optimal interpolation of the archival
data, we compute the correlation functions and analyze the space and time variations of the statistical structure of the fields.
On the sea surface, the thermohaline fields are spatially inhomogeneous. Thus, the correlation functions are anisotropic in
the region of the northwest shelf and close to isotropic in the inner parts of the sea. The values of correlation length vary
from season to season. In the layer of pycnocline, the temperature and salinity fields are anisotropic. In the zonal direction,
the correlation length is 2–3 times greater than in the meridional direction. The indicated anisotropy becomes stronger in
the winter season and weaker in the summer season as a consequence of the seasonal variability of large-scale circulation.
We study the dependence of the error of reconstruction of the fields by the method of optimal interpolation on the form of
approximation of the correlation functions with regard for anisotropy.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 51–65, January–February, 2008. 相似文献
7.
By using the archival hydrological data for 1955–1998, we analyze the trends of deep-water thermohaline characteristics of
the Black Sea and their interannual and decadal variability. It was discovered that the level of salinity increased at depths
greater than 1000 m in the west part of the sea from the mid-1950-s till the early 1980s and the opposite trend was observed
for the next 15–20 yr. The average rate of increase in the deep-water salinity between 1960 and 1980 and its decrease after
1980 was equal to 0.05‰ per 20 yr. These facts demonstrate that the water exchange through Bosporus was intensified for the
first 25 yr of the analyzed period and weakened for the next 20 yr. The interannual variability with a typical period of 6.5
yr and a quasi-20-yr periodicity are detected against the background of the parabolic trend.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 18–30, July–August, 2006. 相似文献
8.
G. K. Korotaev P. N. Lishaev V. V. Knysh 《Izvestiya Atmospheric and Oceanic Physics》2016,52(9):961-973
The methodology of joint processing of the satellite altimetry and occasional hydrological observations in the Black Sea for 1993–2012 is developed. The original technique for reconstruction of the 3D temperature and salinity fields in the deep-sea part is proposed and implemented. This technique makes it possible to identify the depths at which a contribution of adiabatic processes to the deformation of the temperature and salinity profiles of the sea is predominant. Daily-averaged 3D fields of the seawater temperature and salinity in a baroclinic layer on a regular grid are reconstructed. The evaluation of accuracy of the reconstructed temperature and salinity arrays is performed by comparing them with the data of hydrological exploration. Structures of the temperature and salinity fields are correlated naturally with topography of the altimetric level and clearly indicate the synoptic variability. Seasonal and interannual variabilities of the kinetic energy (averaged over horizons of the 63–400 m layer) of the geostrophic currents calculated using the dynamic method makes it possible to reveal a sharp increase in the kinetic energy of the currents in the winter season of 2002. A high correlation is found between the interannual variability of the ERA-Interim wind stress curl averaged over the surface of the deep sea part and the kinetic energy of the geostrophic currents in the 63–400 m layer. 相似文献
9.
We discuss the results of the numerical experiment aimed at the simulation of the behavior of currents and transformations
of the temperature and salt modes in the Sevastopol Bay in January–February 1997. In the numerical analysis, we use actual
data on the velocity and direction of the wind, sea surface temperature, and the discharge of River Chernaya. It is shown
that the circulation and structure of hydrological fields are mainly connected with the direction of the wind, its intensity,
and variability in the course of time. Since the analyzed water area is shallow, the currents inside the bay undergo rapid
transformations (less than for an hour after changes in the wind). At the same time, the transformations of the thermohaline
fields are slower. Due to the inflow of fresh waters of River Chernaya and salt waters from the open sea through the strait,
the structure of thermohaline fields formed in the bay is nonuniform (both in the vertical and horizontal directions). The
distribution of salinity plays the main role in the formation of the vertical stratification, which is natural for the winter
season. Due to the process of freshening of water, a quite high vertical salinity gradient is formed in the upper layer of
the sea. As a result, the process of cooling does not lead to the appearance of convection and inversions of temperature are
formed in the case where warmer waters are located in the bottom layers.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 60–76, March–April, 2005. 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.
G. K. Korotaev A. S. Sarkisyan V. V. Knysh P. N. Lishaev 《Izvestiya Atmospheric and Oceanic Physics》2016,52(4):418-430
A retrospective analysis has been done for the hydrophysical fields of the Black Sea for 1993–2012 with the assimilation of undisturbed monthly average profiles of temperature and salinity that were obtained by using an original procedure of joint processing of satellite altimetry and rare hydrological observations. The accuracy of the reconstructed fields of temperature and salinity of the Black Sea is evaluated by comparison with the data of sounding from the hydrological stations and the Argo floats. A comparative analysis is performed for the integral characteristics of the fields of temperature, salinity, and kinetic energy with the same characteristics of the reanalysis for 1992–2012 that assimilated the average annual profiles of temperature and salinity, surface temperature and altimetry level of the sea after being adjusted with respect to climate seasonal variability. The proposed procedure of the reanalysis execution allows a more precise reconstruction of the interannual variability of temperature and salinity stratification in the main pycnocline. The correlation between the annual and seasonal variability of the eddy of the wind friction tangential stress and the average kinetic energy at the levels is revealed. 相似文献
12.
The seasonal climatic circulation of the sea reconstructed on the basis of assimilation of new arrays of many-year average
hydrological data in a model is analyzed. Five layers are discovered in the structure of climatic currents in the sea in depth:
the surface Ekman layer (∼ 10 m), a layer with small vertical gradients of the kinetic energy (∼ 10–60 m), a layer with relatively
high vertical gradients of the kinetic energy (∼ 60–150 m), a layer with gradual decrease in the kinetic energy and intensification
(from 250–350 m) of the east cyclonic gyre and Batumi anticyclonic eddy (∼ 150–1000 m), and an abyssal layer characterized
by an almost barotropic velocity (∼ 1000–2000 m). The specific features of the seasonal evolution of currents at these depths
are investigated. It is shown that the key role in the formation of deep-water circulation of the sea is played by the south
east flow, east cyclonic gyre, and Batumi anticyclonic eddy.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 28–45, November–December, 2005. 相似文献
13.
14.
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
15.
We realize the algorithm of adaptive statistics of forecasting errors for the assimilation of the climatic fields of temperature
and salinity in the σ-coordinate model of the dynamics of the Black Sea. The principal relations of this algorithm and its
simplified version based on the Kalman filter are presented. The distinctive features of realization of the algorithm specified
by the model are discussed. We also present the results of comparison of the hydrophysical fields of the Black Sea reconstructed
according to the algorithm of adaptive statistics and a simplified scheme of assimilation of the climatic data. It is shown
that the dependence of sources in the transport equations (heat and salt diffusion) on the four-dimensional variances of forecasting
errors and threedimensional measurement errors enables one to reconstruct the mutually adapted climatic parameters of the
sea more exactly. 相似文献
16.
We present the results of analysis of the variability of hydrometeorological and hydrophysical fields near the west and southwest
coasts of Crimea on scales varying from 1–100 days to 1–11 yr according to the data of long-term routine (4–8 h) observations
performed at the coastal marine hydrometeorological stations. New methods of filtration and spectral analysis are used to
reveal the characteristic time scales of variability including the quasiperiodic and periodic components and study the physical
processes responsible for the indicated variability. Special attention is given to the analysis of correlation between the
periodic variability of the fields in the atmosphere and in the coastal zone on different time scales.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 22–36, January–February, 2006. 相似文献
17.
In the summer seasons of 2004–2007, the intensive runoff (cascading) of the Antarctic shelf water (ASW) down the shelf and
continental slope was revealed thanks to the recording of numerous thermohaline profiles across the shelf and continental
slope of the Commonwealth Sea and Prydz Bay. The quickly executed profiles (4–10 h) with submesoscale resolution (near the
shelf’s edge, the scale was even eddy-determinative, i.e., within 1.9–5.6 km), in combination with the fine-structure sounding
and fine vertical resolution of the near-bottom boundary layer, provided a qualitatively new level of understanding the natural
data. The detailed analysis of the temperature, salinity, and density patterns revealed the regularities and peculiarities
of the ASW shelf and slope cascading. The intensive ASW cascading near the shelf break and lower part of the slope can be
forced (appearing as discrete frontal meanders) or free (appearing as discrete plumes) and often has a wave-eddy character.
The field observational data confirmed the obtained representative estimates of the elements of the ASW slope cascading. The
basic area of the ASW formation is near the Amery Shelf Ice, from where the ASW spreads to the northwest, goes around the
Fram Bank, and flows down the continental slope. The evaluative contribution of the ASW slope cascading to the ventilation
of the deep and slope water of the Southern Ocean (near the shelf break 70 km long where the ASW cascading was observed) is
Q
K
= 0.04–0.24 Sv, which agrees well with the analogous estimates obtained in other regions of the Antarctic. 相似文献
18.
O. R. Andrianova 《Physical Oceanography》1997,8(2):117-122
The paper considers the correlation between the variability of river discharges in the northwestern Black Sea and water salinity
(from 1962 to 1994). As the most complete series, we have chosen salinity data collected at the port of Odessa. The dominant
oscillations in the intra-annual variability of river discharges (Danube, Dniester, Dnieper, Yuzhny Bug) and salinity attain
about 2–3 months and one year, respectively. In the inter-annual variability of river discharges and water salinity, cyclicities
equal to about 4–6 months and 9–12 years, respectively, have been identified. Through analysing the inter-annual variations,
an inversely proportional dependence has been found between the overall river discharges and salinity (between discharges
in April and salinities in May, the correlation coefficient has amounted to −0.61). For each river, we have obtained the following
dependences: for Odessa-Dniester, −0.72; and for Odessa-Danube, −0.65.
Translated by Vladimir A. Puchkin. 相似文献
19.
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.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 30–42, July–August, 2005. 相似文献
20.
Yu. V. Artamonov N. P. Bulgakov P. D. Lomakin E. A. Skripaleva 《Physical Oceanography》2006,16(5):299-311
We study the seasonal and interannual variations of the field of sea-surface temperature (SST) in the Southwest Atlantic on
the basis of the analysis of three data arrays, namely, the Levitus-Boyer-1994 hydrological array, the WOD-98 actual database,
and the data of satellite measurements of SST. We perform the comparative analysis of the amplitude-phase characteristics
of the annual course of the SST field and discuss the distinctive features of its seasonal and interannual variations. It
is shown that the results obtained by using different data arrays are in good agreement. The values of the coefficient of
linear correlation are equal to 0.7–0.9. It is discovered that the maximum seasonal variations of SST are observed in the
zone of confluence of the Falkland and Brasil Currents in the vicinities of the South Subtropical and Antarctic Polar fronts.
The minimum seasonal variations are recorded in the Antarctic region and in the Weddell Sea. The satellite data demonstrate
that the level of interannual variability is high in the zones of climatic fronts.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 62–76, September–October, 2006. 相似文献