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21.
We compare the shape and position of some plasma formations visible in the polar corona with the cyclic evolution of the global
magnetic field. The first type of object is polar crown prominences. A two-fold decrease of the height of polar crown prominences
was found during their poleward migration from the middle latitudes to the poles before a polar magnetic field reversal. The
effect could be assigned to a decrease of the magnetic field scale. The second type of object is the polar plumes, ray like
structures that follow magnetic field lines. Tangents to polar ray structures are usually crossed near some point, “a magnetic
focus,” below the surface. The distance q between the focus and the center of the solar disk changes from the maximum value about 0.65 R
⊙ at solar minimum activity to the minimum value about 0.45 R
⊙ at solar maximum. At first glance this behaviour seems to be contrary to the dynamics of spherical harmonics of the global
magnetic field throughout a cycle. We believe that the problem could be resolved if one takes into account not only scale
changes in the global magnetic field but also the phase difference in the cyclic variations of large-scale and small-scale
components of the global field. 相似文献
22.
V. I. Kuzin G. A. Platov E. N. Golubeva 《Izvestiya Atmospheric and Oceanic Physics》2010,46(6):770-783
A numerical simulation with a coupled sea-ice model of the Arctic and North Atlantic oceans is used to study the influence
that the interannual variations in the Siberian river discharge have on the distribution and propagation of freshwater in
this region. In numerical experiments we compared simulations with the use of observational data on the discharge of the most
significant Siberian rivers (Ob, Yenisei, and Lena) against the results of climatic seasonally average variations of their
discharges. This comparison showed that the interannual variations may have significant consequences despite their smallness
when compared with oceanic-scale water transport. These consequences include (1) the intensification of either cyclonic or
anticyclonic components of motion of the subsurface Arctic Ocean waters and, as a result, the redistribution of freshwater
fluxes from Arctic regions between the Fram Strait and the straits of the Canadian Archipelago. A change in the store of fresh
Arctic Ocean waters due to interannual variations in the Ob, Yenisei, and Lena discharges is approximately ±400 km3, whereas the volume of water redirected in this regard, which forms a link between some straits, reaches 15 thousand km3. On the other hand, (2) insignificant changes in the propagation direction of freshwaters are multiply enhanced in the process
of their motion in the North Atlantic as part of the subpolar gyre because of their smaller or larger involvement in the processes
of vertical mixing. As a result of this, anomalies of freshwater develop considerably far from the river mouths, like in the
region of the Azores islands, and are 5–6 times larger than the maximum values of the accumulated variability volumes of the
river discharge. 相似文献
23.
A series of H-filtergrams, covering about 42 min, was studied in order to obtain quantitative data on the oscillations of the visible chromosphere boundary and on the regularity in position of spicule groups along the limb. The results obtained reveal the existence of relatively slow vertical oscillations (a background) superimposed with those of 5 min period. A horizontal dimension of a spicule group 4000 km; a change of the chromosphere height within the latter occurs practically synchronously. A good correlation of height changes for groups of 25000 km apart is observed. 相似文献
24.
V. I. Kuzin G. A. Platov E. N. Golubeva V. V. Malakhova 《Izvestiya Atmospheric and Oceanic Physics》2012,48(1):102-119
Variations in hydrophysical parameters in the Arctic Ocean and the North Atlantic are studied on the basis of numerical simulation
with the use of an ocean circulation model (including ice formation and drift). The main circulation and ice-drift modes have
been ascertained depending on atmospheric cycles. The possibilities of the parameterization of intermediate and deep water
formation in numerical models of polar ocean dynamics are considered. The effect of the interannual variability of the discharge
of Siberian rivers on the distribution and propagation of fresh water in this region are estimated from numerical experiments.
The simulation results of the propagation of the dissolved methane from Siberian rivers are presented. 相似文献
25.
Yu. V. Platov 《Solar physics》1973,28(2):477-485
The dynamics of small surges has been studied using filter and spectral observations in the H line. The surge evolution allows the division into two stages which follows from the observational results. The first stage includes an abrupt H line broadening and the upward acceleration of the surge material. The second one is the inertial motion of the surge plasma along the magnetic force lines. Surges are probably produced by the plasma raking-up which is connected with the growth of the local magnetic field. 相似文献
26.
Specific optical phenomena observed in the upper atmosphere layers and connected with launches of powerful solid-propellant rockets are considered: the development of spherically symmetric gas-dust formations having the shape of an extending torus in the image plane and the formation of regions with intense blue-green (turquoise) glow observed under twilight conditions along a rocket’s flight path. The development of clouds can be represented by the model of a strong explosion occurring at the stage separation of solid-propellant rockets in the upper atmosphere. A turquoise glow arises as a result of resonance scattering of solar radiation on AlO molecules that are formed when metallic aluminum in the composition of fuel interacts with atmosphere components and combustion products. 相似文献
27.
Nikolayshvili S. Sh. Kozlov S. I. Platov Yu. V. Repin A. Yu. 《Geomagnetism and Aeronomy》2019,59(4):488-492
Geomagnetism and Aeronomy - A sequence of digital images of a gas–dust cloud of combustion products of solid fuel that formed during the separation of rocket stages is analyzed. The images... 相似文献