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M. A. Zel’dovich Yu. I. Logachev G. M. Surova K. Kecskemety I. S. Veselovskii 《Astronomy Reports》2016,60(7):687-693
The energy spectra and relative abundances of 3He, 4He, C, O, and Fe ions with energies of ~0.04–2 MeV/nucleon are studied using data from the ULEIS instrument on board the ACE spacecraft obtained during quiescent periods in 2006–2012. During the unique, prolonged minimum between cycles 23 and 24, 35 quiescent periods were distnguished, during which solar-wind flows from near-equatorial coronal holes (CHs) were detected. It is shown that the C/O and Fe/O ratios for suprathermal ions correspond to the relative abundances of the corresponding thermal ions in the fast and slow (Maxwellian) solar wind (SWICS/ACE), while the 4He/O ratio exceeds the corresponding ratio in the solar wind by a factor of two. The intensities of the 3He, 4He, C, O, and Fe suprathermal ions in outflows from CHs grow with the speed of the solar wind. This indicates that, in periods ofminimumsolar activity, suprathermal ions from CHs represent a high-temperature “tail” of the solar wind. An additional flux of suprathermal helium ions may also be contributed by other external sources. 相似文献
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The relative abundances of suprathermal (with energies ～0.04–2 MeV/nucleon) 3He, 4He, C, O, and Fe ions and the energy spectra of 3He and Fe ions in near-Earth space during quiescent periods of solar activity are studied. Measurements obtained with the ULEIS instrument onboard the ACE spacecraft during the 23rd and 24th solar cycles are used. Substantial differences in the energy spectra of suprathermal ions in the 23rd and 24th solar cycles are observed for the selected quiescent periods. Appreciable differences in the energy dependences of the relative ion abundances are also found. One possible explanation for the results obtained is that the background ions were accelerated to suprathrmal energies under different conditions in the solar corona in these two cycles. 相似文献
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Bazilevskaya G. A. Daibog E. I. Logachev Yu. I. Vlasova N. A. Ginzburg E. A. Ishkov V. N. Lazutin L. L. Nguyen M. D. Surova G. M. Yakovchouk O. S. 《Geomagnetism and Aeronomy》2021,61(1):6-13
Geomagnetism and Aeronomy - Homogeneous series of solar cosmic-ray events for four solar-activity cycles against the background of decreased activity in cycles 23 and 24 are considered. The number... 相似文献
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E. I. Daibog K. Kecskeméty L. L. Lazutin Yu. I. Logachev G. M. Surova 《Astronomy Reports》2017,61(12):1073-1081
Variations in the flux of Jovian electrons near the Earth in two synodic cycles of the Earth–Jupiter system, in 1974–1975 and 2007–2008, are considered. In the 1974–1975 cycle, Jovian electrons were observed by IMP-8 during 13 successive solar rotations; electrons were observed by SOHO during 14 solar rotations during the 2007–2008 cycle. The fluxes of these electrons in each solar revolution experienced variations with a characteristic time scale of ~27 d , with the maximum flux near the middle of the rotation. The mean period of the variations does not coincide with the synodic period for the Sun–Earth system, equal to 27.3 d . The mean variation periods for the electron fluxes were 26.8 d in 1974–1975 and 26.1 d in 2007–2008. The detected variations are interpreted as reflecting variations in the structure of the solar wind speed and associated magnetic traps, the confinement time of the electrons in thesemagnetic traps, and the influence of the relative positions of the Earth and Jupiter in space. 相似文献
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Predicting the impact of global warming on soil water resources in marginal forests of the Middle Volga Region 总被引：2，自引：0，他引：2
The response of local forest ecosystems to changes in summer soil moisture content in the context of possible climate changes.
A procedure for local hydrological forecasting is presented. Calculations based on prediction climate models GISS and HadCM3
for forest ecosystems on zonal ecotones between forest and steppe showed a progressive development in the XXI century of a
thermoarid trend with pronounced soil drying during the vegetation period, which should result in decay of broad-leaved and
mixed forests and their replacement by small-leaved-pine and oak-grove forest-steppe. 相似文献
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The ion composition of fluxes of charged particles in interplanetary space with energies ∼0.03–10 MeV/nucleon are studied
during quiet periods in the 23rd solar-activity cycle using data from the ACE spacecraft. Apart from the activity minimum,
the Fe/O ratio during such periods corresponds to either the relative abundances of ions in particle fluxes accelerated in
solar flares or the mean abundances of elements in the solar corona. At the cycle minimum, this ratio takes on values characteristic
for the solar wind. These results indicate that the background fluxes of low-energy particles in the phases of the growth,
maximum, and decay of the solar cycle include significant contributions from both coronal particles accelerated to suprathermal
energies and particles accelerated in small impulsive solar flares. The particle fluxes from such flares are distinguished
by an enhanced abundance of iron ions. 相似文献
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A structural-functional modeling of the mountainous physical-geographical country has been carried out, based on its conceptual representation as an oroclimatic system. The study revealed a statistically reliable mapping of phytobiota productivity onto the coordinates of a multidimensional ecological space, i.e. the mountain morphostructure, hydrothermics and zonal-regional structure of vegetation cover. 相似文献
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Bazilevskaya G. A. Logachev Yu. I. Daibog E. I. Vlasova N. A. Ginzburg E. A. Ishkov V. N. Lazutin L. L. Nguyen M. D. Surova G. M. Yakovchuk O. S. 《Geomagnetism and Aeronomy》2021,61(5):773-779
Geomagnetism and Aeronomy - Type-II radio emission often accompanies events in solar cosmic rays and is an indicator of the propagation of a shock wave in the solar corona. Conversely, the shock... 相似文献
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Data from the ULEIS instrument aboard the ACE spacecraft are used to study the energy spectra of 3He and 4He ions produced during periods of the quiet Sun in the 23rd solar cycle in the energy range ～0.08–2 MeV/nucleon. Differences in the spectra and 3He/4He relative abundances for three groups of quiet periods dominated by different sources of ions are demonstrated: weak impulsive solar flares, particles of the solar corona, and solar wind particles accelerated to energies of several MeV/nucleon. 相似文献
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A case study is made of the Mendeleev volcano (Kunashir Island, Southern Kuril Chain) to carry out a quantitative assessment of the influence of magmatic energy of an active volcano on the thermal regime of the soil and the ground-level air level as well as on the water balance and forest formation processes in the insular volcanic landscape. It is established that the influent channels of steam-hydrotherms cause an anomalous rise in soil temperature thereby having a substantial influence on the structure and functioning of forest ecosystems. Using a specially developed method, we calculated the geotherm-caused temperature anomalies in the soil. Calculations showed that the forest communities of the Mendeleev volcanic landscape evolved into existence and persist under the same heat and energy conditions as their zonal marginalmainland counterparts. The active volcano compensates for a deficiency in the climatic resource and ensures a stable functioning and a structural configuration of these “climatically unjustified” (extrazonal) island-arc ecosystems. We have empirically substantiated the proposition that geothermal energy of passive volcanoes serves as the factor for acceleration evolution of the insular phytobiota. This constitutes the phenomenon of biogeocenological organization of the volcanogenic landscape in the continent-to-ocean transition zone. It is shown that the magmatic geotherms of the Mendeleev volcano promoted the transgression of species and whole communities from southern areas to this boreal-forest region. We examine the rearrangement of the forest cover toward an increase in its floro- and phytocenotic diversity, the formation of relatively stable boreal-subboreal forest ecosystem with subtropical relicts as well as rudimentary buffer forest communities. It is demonstrated that a geothermal heating of the soil on the slopes and at the foot of the volcanoes of the Kuril Ridge is a large-scale (rather than an exceptional) phenomenon in the hydrothermal regime of forest ecosystems of island-arc ecoregions. 相似文献
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