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1.
To study the long-term variability of the thermohaline and dynamic characteristics of the Black Sea, we use three versions of climatic fields, namely, the fields reconstructed in the model according to the old (1903–1982) and new (1903–2003) hydrological climatic data arrays of temperature and salinity and according to the data of satellite altimetry. The analysis of the altimetry-based climatic fields confirms the distinctions (established earlier according to the old and new data arrays) in the seasonal variability of the integral characteristics of temperature and salinity and in the structures of hydrophysical fields in the sea. It is shown that, in the winter-spring season, the thermohaline fields reconstructed according to the new and altimetry data arrays are characterized by a small elevation of the halocline (pycnocline) and the upper boundary of the cold intermediate layer. In all seasons, the altimetry-based surface geostrophic currents contain numerous mesoscale eddies with different signs of rotation. Moreover, in all seasons, the Rim Current reconstructed according to the altimetry data is characterized by a narrower jet almost along the entire its length. This jet is especially intense near the coasts of West Anatolia. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 3–17, July–August, 2006.  相似文献   

2.
On the basis of the many-year-average seasonal data array of temperature and salinity presented on a scale of one-degree averaging, by using a special quantitative criterion, we reveal a climatic frontal zone and determine both its physical and hydrological characteristics (such as the length width, and thickness of the frontal layer and the temperature, salinity, and density gradients) and its geographic coordinates. The many-year average seasonal variability of these characteristics is analyzed. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

3.
On the basis of the data array of many-year average seasonal values of temperature and salinity represented for a one-degree scale of averaging, by using a quantitative criterion, we select the climatic discharge frontal zone of the Amazon, determine its physical and hydrological characteristics: length, width, thickness of the frontal layer, temperature, salinity, and density gradients, and specify its geographical coordinates. We also describe the many-year average interseasonal variability of these characteristics. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

4.
We construct a numerical model of the evolution of the structure of an oceanic thermocline in the presence of “salt-finger” convection. The model explains the formation of a piecewise homogeneous vertical structure of the temperature and salinity fields in the ocean. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

5.
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   

6.
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   

7.
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   

8.
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   

9.
A near-bottom pressure equation consistent with the original set of difference equations is derived in the framework of a numerical energetically-balanced model. The model is used to simulate numerically three-dimensional density and current velocity fields and in the Black Sea for a specific season. The climatic values of temperature, salinity, and tangential wind stress during summer are applied as the original conditions. Analysis of the hydrophysical fields at the final moment of integrating is performed. The difference between new data and data derived earlier is demonstrated.Translated by V. Puchkin.  相似文献   

10.
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   

11.
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   

12.
The results of research into the seasonal variability of hydrothermodynamic characteristics of the Black Sea are presented. These have been obtained using field data on the fields of temperature, salinity, and wind, and by mathematical modelling. The seasonal variability of the current and heat content fields and of the cold intermediate layer and other hydrophysical characteristics is discussed.Translated by Mikhail M. Trufanov.  相似文献   

13.
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   

14.
We describe a differential approach to the spectral composition of thin thermohaline inhomogeneities in the ocean depending on the mechanisms responsible for their generation and demonstrate the possibilities of this approach in getting realistic hydrophysical results. The statistical classification of fine-structure fluctuations according to their origin is performed on the basis of the joint analysis of the temperature, salinity, and density spectra computed in a section of the vertical profile where the variation of mean gradients of all three parameters is insignificant. On the basis of the constructed mean spectrum of wave elevations, we estimate the dissipative characteristics of the convection of salt fingers and small-scale internal waves. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
On the basis of the climatic array of hydrological annual and monthly average data on temperature and the data of satellite observations of the surface temperature of the ocean, we refine the annual average structure of the temperature fronts and study their seasonal variability in the east part of the Tropical Atlantic in the meridional sections made along 30, 20, and 10°W, 0°, and 10°E. It is shown that the maximum intensity and seasonal variations are typical of the North Subequatorial and South Tropical Fronts varying with predominant annual period. We revealed a delay of 2–3 months in the attainment of the maximum intensity of the South Tropical and South Subequatorial Fronts in the west-east direction. Various mechanisms specifying the seasonal variability of the surface and subsurface North and South Subequatorial Fronts are discussed. There exists good agreement between the specific features of the seasonal variability of characteristics of the fronts established according to the hydrological and satellite data. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 46–59, March–April, 2005.  相似文献   

16.
The aim of the present work is to reconstruct the space and time variability of the three-dimensional fields of currents, temperature, salinity, and density in the Sevastopol Bay under the influence of the actual external factors in 1999. For this purpose, we use a version of the numerical multilayer model on the σ-coordinates. A vast array of the data of observations accumulated as a result of regular monitoring of the Sevastopol Bay contains, in particular, the data on the sea-surface temperature measured with six-hour intervals (at the hydrometeorological station located near the center of the bay) and almost monthly vertical profiles of temperature and salinity obtained at seven hydrological stations. The comparison of the numerical results with the data of observations enables us to conclude that, in general, the model fairly correctly describes the space structure and rearrangements of the fields of temperature and salinity. Among the most important distinctions, we can mention the fact that the fresh river water penetrating into the bay is mixed with seawater faster than predicted by the model. We also discuss the causes of these distinctions. Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 23–39, September–October, 2008.  相似文献   

17.
We determine the zones of maximum horizontal gradients of thermohaline characteristics and climatic frontal zones in the Tropical Atlantic and their behavior as functions of time and spatial variables on the basis of the climatic array of data on temperature and salinity. It is shown that the zones, where the maximum horizontal temperature, salinity, and density gradients coincide, are located in the northern and southern tropical frontal zones. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
On the basis of the satellite and ship data of many-year observations, we parametrize the albedo of the ocean-atmosphere system both for the conditions of “fair weather” and for the maximum and climatic optical thicknesses of oceanic clouds. These results are used to develop a procedure of practically exact reconstruction of the monthly average fluxes of integral solar radiation and the radiation budget over the ice-free surface of the oceans according to the data of satellite measurements of albedo (Nimbus NOAA satellite, 1974–1983) for arbitrary conditions of transparency of the atmosphere and cloudiness. We determine the current and climatic monthly average values and the characteristics of interannual variability of all components of the radiation mode of the ocean-atmosphere system with a spatial resolution of 500×500 km. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

19.
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   

20.
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   

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