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We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   
2.
In the present work, we generalize the results of our investigations in the field of simulation of hydrophysical and ecological processes in coastal regions of various seas and some closed basins. The developed and applied mathematical models and the results of numerical experiments are briefly analyzed.  相似文献   
3.
We discuss the results of a numerical experiment devoted to the investigation of the variability of the three-dimensional fields of temperature and current velocity brought about by the seasonal variability of external factors: solar radiation, atmospheric fields, discharge of the river Jordan, and water intake for economic necessities. We use a multilayer model in isopycnic coordinates with an upper mixed layer. We set atmospheric factors in the form of monthly average fields that are uniform over space and linearly interpolated in time. We compare the computed fields of heat flux and evaporation through the lake surface, level, temperature, and currents with data of observations. We note a qualitative agreement of temperature fields during the whole year and current velocities in winter when the lake is, in fact, barotropic. In summer when the lake is stratified, currents in the model turn out to be weaker than in observations.  相似文献   
4.
We describe a software package developed for the visualization of the results of hydrothermodynamic modeling and called the User Visualization Tool (UVT). The contemporary requirements to the software of this sort are discussed. The UVT software enables one to perform the efficient construction of the maps, vertical profiles, time series, and the sections of variability of the scalar and vector variables of state of the sea. By using the models of the Mediterranean and Adriatic Seas as an example, we demonstrate some possibilities of the package, perform its comparison with similar software packages, and estimate the trends of its subsequent development. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 59–68, September–October, 2007.  相似文献   
5.
Within the framework of the integral model in isopycnic coordinates including the upper mixed layer, we study the rearrangement of temperature and salinity fields in the Dead Sea. It is forced by the variability of atmospheric factors and mass fluxes through the lateral boundaries of the basin, which are connected with the freshwater run-off to the sea and the outflow from the sea to the shallow south bay, where evaporator installations for salt extraction are located. Such factors as solar radiation, wind velocity, air temperature, and relative humidity are prescribed. Evaporation is calculated with the use of a bulk formula, whereas precipitation intensity and discharge through the lateral boundaries are determined as functions of the sea level obtained from observations. This model reflects the specific character of the Dead Sea and takes into account the effect of water salinity on its evaporation, salt concretion, and mechanical evaporation. Comparison with the data of observations shows that the proposed model fairly precisely describes the observed specific features of the thermohaline water structure in the meromictic (1992–1996) and holomictic (1996–2000) periods.  相似文献   
6.
Within the framework of a one-dimensional model taking into account the presence of an upper mixed layer, we compute the seasonal variation of temperature and the concentration of dissolved oxygen in the central part of Lake Kinneret. The temperature conditions of the lake are determined by heat exchange with the atmosphere, and the oxygen conditions depend on gas exchange with the atmosphere and oxygen consumption in sediments as well as on internal sources and sinks. The latter are connected with oxygen supply in the course of photosynthesis and its consumption for the oxidation of labile organic substance in the water thickness. In the period of winter convection from December to February, when the upper mixed layer reaches the bottom, complete aeration of water takes place. The presence of thermal stratification of the lake in the remaining time results in oxygen deficiency under the thermocline.  相似文献   
7.
A method permitting the complete ensemble of characteristics to be reconstructed from a few selected characteristics is suggested. Finding sets of characteristics which ensure a minimum error of reconstruction, as well as the reconstruction procedure itself, requires the invoking of information on the convariance relationships between the characteristics. The method has been applied to determine the wavelengths, optimal for the reconstruction of spectra of sea surface radiance coefficients in the western tropical Atlantic.Translated by Vladimir A. Puchkin.  相似文献   
8.
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   
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