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1.
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   

2.
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   

3.
On the basis of the data of optical investigations performed in the Black Sea, we develop a method for the evaluation of the spectral values of underwater quantum irradiance within the band of photosynthetically active radiation according to the depth of visibility of a Secchi disk and the intensity of illumination of the sea in luxes. The method is based on the use of the correlations between the following optical parameters: of the vertical daylight attenuation factor α with the depth of visibility of a Secchi disk and of the spectral values of α(λ) within the band of photosynthetically active radiation with α(λmin) for sea waters. This method is applicable in the winter-spring period when the seasonal thermocline is absent, the upper layers of the sea are mixed, and the vertical distribution of α is uniform. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

4.
A formula for the relationship between the spectrum-integrated flux of outgoing long-wave radiation,F cn, and the albedo,A cn, of an ice-free sea surface-atmosphere system has been derived using historical (1974–1983) NIMBUS (NOAA) satellite observations. Also determined is the sensitivity of the system's radiation budget to albedo variations, fluctuations of the sea surface temperature, cloud amount and optical density, depending on the time of the year and latitude.Translated by V. Puchkin. UDK 372.21.17.17+372.21.17.19.  相似文献   

5.
On the oceanographic platform of the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences, we performedin situ investigations of surface waves based on the analysis of the fluctuations of radar signals at a wavelength of 1.2 cm. We analyzed both the traditional modulation transfer function used to describe variations of the scattering cross section for the scales of surface waves and the correlation of mean variations of the level of radar signals with the group structure of waving. This is of interest for applications in medium-resolution radar systems (−200–500m) recording the group structure of waving in the process of its smoothing. The experimental estimations of the amplitude of variations of radar signals caused by the group structure of waving are in good agreement with numerical results obtained with the help of a two-scale model of scattering of radar signals by the sea surface. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

6.
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   

7.
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   

8.
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   

9.
We show that the parameters of primary radar images obtained from theSich-1 satellite depend on the mode of survey and that the time dependence of the coefficient of correction of amplification in the channel of formation of radar signals is nonlinear. We propose to process radar images of the sea surface by using the so-called Bragg normalization of signals, which enables one to get a physically correct dependence of specific effective scattering surface on the elevation angle. We also consider a procedure of determination of the dependence of specific effective scattering surface of the sea on the wind velocity on the basis of the data accumulated by the side-looking radar of theSich-1 satellite. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

10.
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   

11.
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   

12.
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   

13.
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   

14.
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   

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.
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   

17.
The evolution of an ensemble of intense vortices in the β-plane is numerically simulated. In the process of evolution, vortices interact either directly or by means of the Rossby waves emitted by them. We show that the mean displacements of vortices of the ensemble along the meridian and, as a result, their energy losses are lower than for the isolated vortices evolving in the β-plane. This means that they are more stable than the isolated vortices. In addition, for vortices in the ensemble, the theoretical dependence of the energy of a vortex on its displacement from the initial latitude obtained for the motion of an intense isolated vortex in the β-plane is in good agreement with the experimental data. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
In the Boussinesq approximation, we study baroclinic topographic waves trapped by the flat meridional slope. The existence of these waves is explained by stratification, inclined bottom, and Earth's rotation. We deduce the evolutionary equation for the square of the envelope of a narrow-band wave packet of trapped waves. In the second order of smallness relative to the wave amplitude, we find the mean fields of velocity and density induced by the packet. It is shown that, in the limiting case of weakly nonlinear plane waves, the induced current is zonal. In the Northern hemisphere, depending on the slope of the bottom γ1, the sign of the phase velocity σ/k (k is the zonal wave number) is either always positive (for γ11cr) or always negative (for γ11cr). If we neglect the vertical component of the Coriolis acceleration, then γ1cr=0. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

19.
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   

20.
We study possible mechanisms of mixing in the northwest part of the Tropical Atlantic (C-SALT) and show that homogeneous layers in the staircase structure can be observed across the entire frontal zone of the North Equatorial Countercurrent. In the central region of the frontal zone, one may observe horizontal motions of the upper parts of quasihomogeneous layers with respect to their lower parts and an essential role in the exchange processes is played by turbulence. The peripheral regions of the frontal zone are characterized by the presence of horizontal advection and isopycnic mixing. Far from the frontal interface, the principal contribution to the exchange processes is made by double diffusion. We demonstrate that, for the analysis of the vertical buoyancy fluxes caused by salt fingers, one can use both the Stern relation and the “law of 4/3”. Translated by Peter V. Malyshev and Dmitry V. Malyshev.  相似文献   

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