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Water Resources - Based on 1965–2020 series we have shown relationships between the features of the water runoff of the spring flood in mouths of large rivers of North-Eastern Europe and the... 相似文献
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The emergence of photospheric magnetic fields and the dynamics of the associated pattern of vertical motions in a developing active region are studied based on SOHO/MDI data. Objects were selected for which complete time series of data were available, so as to make it possible to determine the onset time of the magnetic-field emergence at the surface and tracing the formation of the first pores. The active regions studied originated near the central meridian. The total area of sunspots in these regions exceeded 100 millionths of the hemisphere at the maximum of active region evolution. A generalized evolutionary scenario is constructed for the magnetic field and vertical motions in the emerging active region. An asymmetry in the Doppler velocities is noted at an early stage of the active-region development, which corresponds to a matter flow from the leading to the trailing end of the emerging Ω-shaped tube. A direct relationship is found between the matter-downflow velocity in the area of the pore development and the growth in the strength of the longitudinal magnetic field. 相似文献
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V. M. Grigoryev L. V. Ermakova I. I. Salakhutdinova A. I. Khlystova 《Geomagnetism and Aeronomy》2009,49(7):823-829
The dynamics of the magnetic field and velocity field during the birth and an early development stage of a major active region
is studied. SOHO MDI longitudinal-component magnetograms, Dopplergrams, and continuum images are used. The presence of an
enhanced material upflow in the photosphere during the passing of the top of the magnetic flux loop, forming the active region,
is revealed. The maximum upflow velosity is 2 km/s and the maximum size of the upflow area exceeds 20000 km. The lifetime
of the upflow is about two hours. The undulating form of the magnetic flux tubes crossing the photosphere is confirmed. A
structural-analysis technique is used to show that the trailing polarity field at the formation stage of the active region
is more highly structured than the leading polarity field. 相似文献
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Analysis of SOHO longitudinal magnetograms and Dopplergrams has revealed the appearance of a region of enhanced upflow of matter in the photosphere when the top of a loop-shaped magnetic flux tube forming a large active region passed through it. The maximum upflow velocity reached 2 km s?1, the maximum size exceeded 20 000 km, and the lifetime was about 2 h. 相似文献
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The results of study of six cores taken from different morphostructural zones in the Mendeleev Ridge area are discussed. Average contents of minerals of the illite group, chlorite, kaolinite, and smectite are about 60, 21, 12, and 5%, respectively. It was found that fluctuations of minerals along the section correlate with variations in sedimentation constraints in the Late Quaternary. Peaks of kaolinite usually coincide with increased contents of the sand fraction, probably, due to its delivery by icebergs. In contrast, illite shows good correlation with the pelite fraction, testifying to its transport mainly by ices and currents. Minerals of the chlorite and smectite groups in the studied cores are less informative. 相似文献
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E. A. Silow D. J. Stom N. A. Basharova A. A. Belyaev N. A. Buntina O. A. Burlakova T. A. Dzuban E. N. Ermakova N. A. Zausaeva A. I. Spivak T. G. Khramtzova G. V. Shahova N. G. Sheveleva N. A. Shestakova 《洁净——土壤、空气、水》1991,19(6):629-634
Fertilization experiments in mesocosms of 1 … 2,000 1 containing up to 0.32 mg/l P and 1.7 mg/l N in summer and in winter did not show any significant changes of the hydrochemical conditions and in the bacterio-plankton. CO2-assimilation (14-C method) is reduced by circa 10= by nutrient doses, whereas the chlorophyll concentration increases significantly due to addition of P and N at the same time in summer, a decrease taking place in winter. The different courses of development are connected with different reactions of individual species of phytoplankton. 相似文献
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Results of an analysis of the double layer kinetic characteristics in the case of kappa distributions are presented. The direct and classical double layers and double layers in a trap have been considered. It has been indicated that the restrictions imposed by the Bom-Block criteria are removed if trapped particle populations between the ionosphere and the electrostatic potential jump and between conjugate potential jumps are considered. The dependence of particle fluxes through the double layer in a trap, replacing the Langmuir criterion of a classical double layer, has been obtained. The applicability of the obtained results to the solution of the problem of particle acceleration in the auroral plasma has been discussed. The dependence of the current carried by precipitating magnetospheric electrons on the field-aligned potential jump and kappa distribution characteristics has been obtained. 相似文献
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The formation of filaments in solar bipolar active regions is investigated, giving particular attention to the relationship between this process and the pattern of supergranular convection. SOHO MDI and Kitt Peak magnetograms and Hα filtergrams are used. The large decaying active region NOAA 8525 is considered over the period May 4–7, 1999. The boundaries of supergranules are identified as concentrations of the line-of-sight photospheric field in magnetograms. Filaments in the central part of the active region are studied; as a whole, they are aligned with the supergranule boundaries. Variations in the magnetic field in this period were manifest primarily in the form of “cancellations” and spatial-redistribution processes consistent with the pattern of developing supergranules. These factors created the conditions necessary for the formation of a filament stretched across the entire active region; i.e., the straightening of the polarity-inversion line and reduction of the horizontal gradients of the magnetic field. One possible explanation of the results is that the magnetic-field component along the filament axis is associated with the vortical structure of horizontal flows in the supergranulation cells. 相似文献
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In this paper the magnetic flux distribution of bipolar active regions at the sunspot development stage is analyzed. It is shown that the ratio of the total sunspot area in an active region to the maximum one can be used as a characteristic of the development phase. Such a procedure allows combining the data attributed to different active regions for studying evolutionary changes. The expressions describing the evolution of magnetic flux distribution of bipolar active region were obtained and their interpretation with rise and descent of loop like magnetic flux tube leading to active region formation was justified. 相似文献