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941.
Specific features of variations in the bottom topography of the mid-ocean rift zones with intermediate spreading rates are considered in this work. The rift zones with a transition morphology are analyzed, and the main features of the transition topography are distinguished. Several successive stages of topographic variations, each of which is characterized by a specific relative position of the topographic features of the rift zone cross section, have been distinguished based on an analysis of the character of rift zone topographic variations in going from axial rises to rift valleys. The specific features of variations in the structural segmentation of rift zones with intermediate spreading rates, depending on the morphological changes, have been established. The thermal models of the structure of the rift zone magmatic formations have been considered, and the geodynamic relations of the magmatic systems with the specific features of the morphology and the structural segmentation of the mid-ocean axial zones with the intermediate spreading rates have been discussed. 相似文献
942.
D. V. Kulyamin E. M. Volodin V. P. Dymnikov 《Izvestiya Atmospheric and Oceanic Physics》2009,45(1):37-54
The problem of simulating quasi-biennial oscillations (QBOs) of zonal velocity in the equatorial stratosphere in atmospheric general circulation models is considered. In accordance with the results from Part I of this study on the basis of the models developed at the Institute of Numerical Mathematics of the Russian Academy of Sciences (INM RAS), the possibility of implementing (in these models) mechanisms of QBO excitation through both the interaction of planetary waves with the mean flow and breaking of short gravity waves is investigated. A new high-resolution 2° × 2.5° × 80 version of the INM RAS model is designed, a climate simulation with the two 2° × 2.5° × 39 and 2° × 2.5° × 80 versions of the INM RAS model is briefly described, results of spectral analysis of equatorial wave activity are presented, and the QBO formation processes in these models are considered in detail. For the new 2° × 2.5° × 80 model, realistic QBOs of zonal wind are obtained as the result of the action of both mechanisms. 相似文献
943.
A. V. Vivchar K. B. Moiseenko R. A. Shumskii A. I. Skorokhod 《Izvestiya Atmospheric and Oceanic Physics》2009,45(3):302-313
The task of identifying climatically significant regional anthropogenic emissions and estimating their contribution to the variability of nitrogen oxides observed at a monitoring station is considered on the basis of NO and NO2 surface concentrations measured at the Zotino background observation station (60°26′ N, 89°24′ E, Krasnoyarsk Territory). The approach used is based on an estimation of the conditional probability of polluted air arriving from individual regions by using the results of calculating backward Lagrangian trajectories in the lower troposphere. It is established that the contribution of air masses supplied from industrial regions in the south of the Krasnoyarsk Territory to episodes of high concentrations of nitrogen oxides (>0.7 ppb) is larger than the contribution from cities and towns located in the south of Western Siberia. The results indicate that anthropogenic sources of pollution substantially affect the balance of minor gases in the lower troposphere on a regional scale and that this factor must be taken into account when observational data from the Zotino background station are analyzed and interpreted. 相似文献
944.
We consider long barotropic waves in a system of two rectangular basins connected by a channel in the case where waves are
generated by the moving region of disturbances of atmospheric pressure passing above one of the basins. By using a numerical
model, we compute the characteristics of the wave process for various values of the parameters of this system. The results
of numerical calculations are compared with the corresponding characteristics obtained for the case of a closed basin. We
also analyze the distinctive features of long-wave processes induced in the presence of the channel.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
945.
We discuss the current state of the problem of experimental investigation of the bottom boundary layer of the Black Sea and
present the data on a new measuring complex (designed and constructed at the Marine Hydrophysical Institute and called the
OLT-D profilometer of the bottom layer) together with some results of its application. On the basis of the analysis of the
data on the distributions of geothermal fluxes and parameters of the bottom boundary layer in the deep-water part of the sea,
we deduce and justify the relations for the evaluation of the critical thickness of the bottom boundary layer as a function
of the intensities of geothermal fluxes. It is shown that the numerical results are in good agreement with the data of direct
measurements of the thickness of the bottom boundary layer.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
946.
N. P. Bulgakov S. N. Bulgakov V. N. Davydova A. Z. Martinez 《Physical Oceanography》1999,10(2):107-121
On the basis of the data ofin situ measurements of the velocities of currents and basic hydrophysical parameters (such as temperature and salinity) carried
out during Cruise 41 of the R/VAkademik Vernadsky, we analyze the structure of the North Brazil Current near the continental slope and in the equatorial abyssal part of the
ocean in winter, establish the regularities of changes in the current velocity with depth, and compare the structures of the
North Brazil and Guiana Currents.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
947.
Cessation of the Norwegian drift net fishery: changes observed in Norwegian and Russian populations of Atlantic salmon 总被引:1,自引:2,他引:1
948.
949.
The paper is concerned with the evaluation of the drift current parameters derived through the use of an analytical model.
In this model, effective when stratification is stable and indifferent, the vertical turbulence coefficient profile is prescribed
by the power function, and hydrodynamic quantities are prescribed using the external parameters of the problem (wind stress,
the Coriolis parameter, and the dimensionless stratification parameter). Model data are compared with the observations of
the upper mixed layer in the vicinity of the oceanic Station C, conducted during one year. It is shown that, under the spring-summer-time
warming conditions, the model at issue is capable of adequately simulating the upper ocean layer dynamics.
Translated by Vladimir A. Puchkin. 相似文献
950.
In application to the Crimean regional centre for satellite data reception, treatment, and dissemination, we have identified
the earth’s satellite-surveyed areas, with orbital heights (H) ranging from 650 to 750 km. This paper shows that for the Ukrainian territory and the Sea of Azov-Black Sea environment
to be monitored, the regional centre’s receiving station must be capable of receiving radar signals from a range of about
1500 km. For typical high-speed radio lines, this may be achieved through the use of a satellite data-receiving station, with
the antenna’s diameter being about 3 m.
Translated by Vladimir A. Puchkin. 相似文献