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781.
Using a three-dimensional nonlinear mathematical model, we study the processes of transfer and diffusion of contaminants in
the Sea of Azov in the presence of stationary currents. Changes in the sea level, surge phenomena, and the direction and velocity
of stationary currents caused by winds with different maximum velocities are analyzed. We estimate the region of applicability
of the linear approximation and the choice of the value of integration steps over space and time coordinates. It is shown
that the growth of the maximum wind velocity increases the contaminated domains and the time of complete dispersion of the
admixture. Solutions obtained in the linear approximation differ slightly from those obtained by using the nonlinear model
for wind velocities up to 5 m/sec.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 52–68, July–August, 2008. 相似文献
782.
The surge phenomena and currents in the Azov Sea caused by variable winds in the presence of stationary currents are studied
by using a three-dimensional nonlinear mathematical model. The specific features of the transformations of impurities in the
water area of the Azov Sea under the joint action of stationary and nonstationary winds are investigated. On the basis of
the results of numerical calculations, we make conclusions concerning the dependence of the period of dissipation of impurities
on the wind velocity and the location of the regions with impurities. It is shown that the variable wind significantly increases
the deviations of the sea level and the area of distribution of the impurity as compared with the action solely of the stationary
currents. 相似文献
783.
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
784.
O. I. Korablev L. V. Zasova A. A. Fedorova A. V. Rodin N. I. Ignatiev T. K. Breus M. N. Izakov B. S. Maiorov A. A. Krivolutsky E. V. Petrova A. Yu. Ivanov A. Yu. Trokhimovskii 《Izvestiya Atmospheric and Oceanic Physics》2009,45(4):503-516
We present here an overview of the results of Russian investigations of planetary atmospheres in 2003–2006 prepared by the Commission on Planetary Atmospheres of the National Geophysical Committee for the National Report on Meteorology and Atmospheric Sciences to the 24th General Assembly of the International Union of Geodesy and Geophysics (Perugia, June 2–13, 2007). 相似文献
785.
M33 luminous stars with MV ≲ -7 and U--B < o are selected in this paper. The spatial distribution of the stars shows a good agrement with the associations and HII regions. However HII regions are absent in the three youngest associations in M33 (t ≈ 5 ÷ 7 × 10yr). It is supposed that the true distance modulus of M33 derived from the brightest blue stars is 24.2. An age gradient across the arms is absent. The spiral arms outlined by the luminous stars differ form those in M31. They are diffuse and wide. The multiarm features of M33 support the stochastic self-propagating model. 相似文献
786.
Doklady Earth Sciences - It is shown that the observed latitudinal zonality of the Ural Fold Belt is determined mainly by the different levels of erosion of different areas. Thus, the deep levels... 相似文献