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Features of the Earth’s Solar Climate Changes in the Present Epoch Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. M. Fedorov
Abstract Calculated insolations of the Earth are analyzed. The main trends in the modern solar climate change are identified: increased latitudinal contrast and smoothed seasonal differences. The correlation of the meridional insolation gradient with the average annual energy transfer in the ocean–atmosphere system is revealed. The features of changes in the annual and semiannual meridional insolation
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Modified 3D Model of a Facular KNOT Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. A. Solov’ev, E. A. Kirichek
Abstract The paper presents a modified version of a previously published 3D model of the solar facular knot (Solov’ev and Kirichek, 2019), which successfully describes the main structural features of the solar facular formations. As in the main model, we use the solution (Schatzman, 1965) in the potential approximation as the basis of the magnetic structure of the facular element. The magnetic profile
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Characteristics of Soft X-Ray Radiation of the Solar Active Region NOAA 1024 Registered by the PINGVIN-M Device in July 2009 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 M. I. Savchenko, P. V. Vatagin, P. B. Dmitriev, M. G. Ogurtsov, E. M. Kruglov, V. P. Lazutkov, D. V. Skorodumov, I. I. Shishov
Abstract The paper presents the results of processing of data on the soft X-ray solar radiation obtained by the PINGVIN-M instrument aboard the KORONAS-FOTON spacecraft in July 2009. The high sensitivity of the device, combined with effective compensation for the magnetospheric background over most of the orbit, made it possible to study in detail the evolution of X-ray radiation from the active region
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Polar and Low-Latitude Faculae in Activity Cycles 23–24 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. G. Tlatov, K. A. Tlatova
Abstract Polar and low-latitude faculae were identified in daily images based on white-light observations from the MDI (1996–2011) and SOHO (2010–2019) space observatories. The boundaries of the faculae were combined with magnetic field observations at the closest possible instant of observation. The time and latitude distributions, as well as other properties of polar and low-latitude faculae, were
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Properties of the Variability of the Solar Constant as an Index of Solar Activity Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 M. I. Ryabov, A. L. Sukharev, L. I. Sobitnyak
Abstract The properties of the solar constant variability are considered according to the results of satellite observations (http://lasp.colorado.edu/home/sorce/data/tsi-data/). The obtainment of satellite data with an accuracy of 0.01% that is devoid of atmospheric influence allows a detailed analysis of variations in this index of solar activity and space weather for solar-activity cycles 21–24.
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Manifestations in the Solar Corona of the Process of Magnetic-Field Generation Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. L. Merzlyakov, L. I. Starkova
Abstract The situation with the reliability of calculations of the magnetic field of the solar corona remains a topic of discussion. There is, in particular, the problem of significantly lower calculated values of the magnetic field than those recorded near the Earth. The authors propose an explanation in which the magnetic fields are underestimated due to the existence of magnetic sources at different
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Relationship of the Magnetic-Field Strength and the Brightness of the Sunspot Umbra and the Center of a Facular Knot Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 I. Zhivanovich, A. A. Solov’ev, V. I. Efremov, N. O. Miller
Abstract Two main features define a sunspot as an object: a strong magnetic field and a low umbra temperature. The same can be said about a facular knot, in the center of which there is a dark micropore, and the magnetic field is several hundred Gauss (which noticeably exceeds the level of equipartition of about 200–250 G), sometimes reaching 1000 or 1200 G. The temperature decrease in these activity
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Comparative Analysis of Terrestrial and Satellite Observations of Photospheric Magnetic Field in an Appendix to Simulation of Parameters of Coronal Holes and Solar Wind Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 I. A. Berezin, A. G. Tlatov
Abstract Data from observations of the photospheric magnetic field at a number of ground stations (STOP, WSO, GONG) and by the SDO/HMI satellite for 2014–2019 are examined in terms of the accuracy of the model calculations of the speed of calm solar wind and the areas of coronal holes obtained on their basis. A high positive correlation was found (R > 0.5) between the simulation results and satellite
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Self-Organized Criticality of Solar Magnetism Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. I. Abramenko
Abstract Self-organization is a property of any nonlinear, dynamic, dissipative system that evolves under the influence of external forces and positive feedback. Self-organization leads to the creation of order from chaos, thus reducing the entropy of the system. As a result, numerous small elements and/or short-lived elements form structures with large spatiotemporal scales. One very important property
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Signs of Preflare Situation in Solar Ultraviolet and Microwave Emission Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 I. A. Bakunina, V. F. Melnikov, A. S. Morgachev
Abstract The spatial dynamics of microwave emission (data from the Nobeyama Radioheliograph) of active regions with a complex magnetic field configuration before powerful flares, as well as the fine structure of active sources of ultraviolet (UV) emission based on AIA/SDO data, are studied. It is shown that there is unsteady behavior of microwave sources, along with the ignition of a system of crossed
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Periods of Extremely High Rates of the Production of Cosmogenic 14 C and Temperature Variation According to Data on the 40 Ar Content in the Ice Layers for the Last 4000 Years Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. A. Dergachev, I. V. Kudryavtsev, Yu. A. Nagovitsyn
Abstract The possible application of temperature reconstructions based on measurement of the 40Ar concentration in ice layers of the Greenland ice sheet to study past solar activity with radiocarbon data is considered. The rate of 14С production and the heliosphere modulation potential from the 2nd millennium B.C. to the middle of the 18th century A.D. is reconstructed with allowance for the Earth’s
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Study of Long-Duration Flares and Associated Chromospheric and Coronal Ejections in Solar Cycles 23 and 24 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. N. Shakhovskaya, I. Yu. Grigor’eva
Abstract— A statistical study of long-duration (long-duration event, LDE) flares in the soft X-ray (SXR) range for solar cycles 23 and 24 is carried out. Graphs of the dependence of the strength of LDE flares and coronal mass ejections (CMEs) on the duration of these flares are constructed. As a result, we find that a significant proportion of LDE flares is not associated with large mass CMEs. This
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Heat Fluxes in Collisionless Magnetohydrodynamic Shock Waves Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. D. Kuznetsov, A. I. Osin
Abstract Properties of solutions for parallel magnetohydrodynamic (MHD) shock waves in collisionless plasma with heat fluxes obtained in the 8-moment MHD approximation are discussed. The domain of upstream shock-wave plasma parameters in which there are solutions that preserve physical meaning of the downstream plasma parameters is determined. New results have also been obtained for the heat fluxes
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Path Integral Method in the Mean-field Model for the Magnetic Vector Potential Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 E. V. Yushkov, C. R. Kamaletdinov, D. D. Sokoloff
Abstract The method of path integrals is used to average the magnetic-induction equation written for the vector potential over the velocity field. This approach avoids the assumption that the random field is two-scale, replacing it with the assumption of short time correlations. As a result of averaging, the classical equation of the mean field is obtained, at least for a homogeneous and isotropic
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24th Cycle of Solar Activity: Geoefficiency of Flares Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 E. A. Bruevich, G. V. Yakunina
Abstract Various aspects of the of geoefficiency of solar-activity phenomena, such as flares and coronal mass ejections (CMEs), are considered. The number of geoefficient events was about two times lower in the 24th cycle than in the 23rd cycle. Statistical data on major flares and the Dst index in different phases of the 24th cycle is compared. Large flares (X-ray class > M5) were analyzed based on
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Gamma Rays Generated in Nuclear Interactions of Protons Accelerated during Solar Flares Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 G. I. Vasil’ev, E. A. Bogomolov
Abstract The article considers 30 solar flare events during which the spectra of solar cosmic-ray (SCR) protons with energies above ~80 MeV were recorded in the course of the PAMELA experiment (July 2006–September 2014) and those with energies above ~0.4 GeV recorded during the AMS-02 experiments (June 2011–September 2014). The Konus-Wind data are analyzed for the same time period (2006–2014), during
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Radiocarbon Data from the Late 18th Century as a Reflection of Solar Activity Variation, Natural Climate Change, and Anthropogenic Activity Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. I. Larionova, V. A. Dergachev, I. V. Kudryavtsev, Yu. A. Nagovitsyn, M. G. Ogurtsov
Abstract— The data on the content of the 14C cosmogenic isotope in the natural archives make it possible to study the solar activity (SA) in the past centuries and millennia. However, the 14C content in the natural archives is influenced not only by the intensity of incoming galactic cosmic rays (GCRs), which are modulated by the interplanetary magnetic field and vary according to SA variations; changes
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Source of Electromagnetic Radiation in Corona and Impedance of the Stationary Magnetic Reconnection Area Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. M. Gubchenko
Abstract A source of high-frequency electromagnetic radiation is formed by energetic particles in the magnetic structures of plasma corona. Energetic particles are formed in the electric and magnetic fields of the dissipative structures of the magnetic reconnection caused by the low-frequency induction process in a hot, collisionless plasma expanding over the magnetization regions. The stationary process
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Evolution of Electric Current and Resistance in the Flare Loop in the Course of Loop Shrinkage Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. V. Zaitsev, A. V. Stepanov
Abstract Analysis of the phenomenon of the shrinkage of a coronal magnetic loop during the impulsive phase of a flare makes it possible to determine both the evolution of electric current in the loop and the loop resistance. We show that the flare process is accompanied by a substantial (two orders of magnitude) increase in the loop resistance along with a slight (~20%) decrease in the electric current
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Energetics of X-Class Flares at the Minima of 22, 23, and 24 Solar Cycles Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 G. G. Motorina, A. L. Lysenko, S. A. Anfinogentov, G. D. Fleishman
Abstract— Quite often powerful flares occur during a decrease of solar activity. In this work, we make an attempt to consider X-class flares at the minima of solar activity cycles as a separate group of events. Out of nine X-class flares we selected three such events that occurred at the minima of solar cycles 22–24: SOL1996-07-09T-09:09 (X2.6), SOL2006-12-13T-10:26 (X3.4), and SOL2017-09-06T-11:53
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Unitary Variation in the Seismic Regime of the Earth: Carnegie-Curve Matching Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 S. A. Pulinets, G. Ya. Khachikyan
Abstract According to data on earthquakes with a magnitude of М ≥ 4.5 recorded on the planet in 1973–2017, a UT variation in the number of earthquakes with an amplitude of ~10% was found and compared with the UT variation in the atmosphere gradient of electric-potential (Carnegie curve), the amplitude of which is ~20%. It is shown that the amplitude of UT variations in the number of deep-focus earthquakes
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Behavior of He ++ Ions at the Front of an Interplanetary Shock Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 O. V. Sapunova, N. L. Borodkova, G. N. Zastenker, Yu. I. Yermolaev
Abstract The variations in the parameters of twice ionized helium ions He++ of solar wind plasma during the passage of the front of the interplanetary shock are studied. Data taken from measurements by the Bright Monitor of Solar Wind (BMSW) installed onboard SPEKTR-R satellite were used to calculate the parameters of the He++ ions: the speed, temperature, and absolute and relative density (helium
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Ground-based Instrument for the Study of Cosmic Ray Variation in Nur-Sultan Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 E. A. Tulekov, V. S. Makhmutov, G. A. Bazilevskaya, Yu. I. Stozhkov, A. K. Morzabaev, M. V. Philippov, V. I. Erkhov, A. S. Dyusembekova
Abstract Cosmic rays are the main factor in atmospheric ionization; they affect the formation of clouds and determine the properties of the global electrical circuit. The mechanisms of atmospheric processes involving cosmic rays are very complex and are far from understanding. Their research requires experimental installations distributed around the world. In this context a cosmophysical complex consisting
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Cyclic Variations, Magnetic Morphology, and Complexity of Active Regions in Solar Cycles 23 and 24 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. V. Zhukova, D. D. Sokoloff, V. I. Abramenko, A. I. Khlystova
Abstract In this paper, 2046 active regions of solar cycle 23 and 1507 active regions of solar cycle 24 observed during the period from May 1996 to December 2018 have been studied. The sunspot groups are distributed according to the recently proposed magneto-morphological classification. Regular active regions (obeing Hale’s polarity law, Joy’s law, and having a leading sunspot that prevails over the
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Luminescence of Lyman–Birge–Hopfield Bands of N 2 in the Earth’s Atmosphere during the Precipitation of High-Energy Electrons Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. S. Kirillov, V. B. Belakhovsky
Abstract The luminescence intensity profiles of Lyman–Birge–Hopfield bands of molecular nitrogen have been calculated for the precipitation into the Earth’s atmosphere of electrons with energies of 10 keV to 10 MeV. With an increase in the energy of electrons penetrating the atmosphere, there is an increase in the contribution of the quenching of the a1Πg N2 state in molecular collisions. This leads
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Influence of the Ionosphere on the Parameters of the GPS Navigation Signals during a Geomagnetic Substorm Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. I. Zakharov, A. A. Chernyshov, W. Miloch, Y. Jin
Abstract The influence of geomagnetic activity on slips of navigation signals of the global positioning system (GPS), as well as an increase in the amplitude of jumps in the total electron content at high latitudes, has been studied in detail. It is shown that the navigation signal of the L2 frequency is subject to more frequent malfunctions than the L1 frequencies, both in calm conditions and during
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Differences in the Dynamics of the Asymmetrical Part of the Magnetic Disturbance during the Periods of Magnetic Storms Induced by Different Interplanetary Sources Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 L. A. Dremukhina, Yu. I. Yermolaev, I. G. Lodkina
Abstract The differences in the dynamics of the asymmetrical part of the geomagnetic disturbance at middle and low latitudes during magnetic storms initiated by different interplanetary sources are analyzed. The analysis is performed with the SYM-H, ASY-H, and Dst indices from the OMNI database during the periods of 58 intense magnetic storms with –270 ≤ Dstmin ≤ –90 nT that were recorded in 1995–2017
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Implementation of Ionospheric Generators in the Numerical Model of the Global Electric Circuit Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 F. A. Kuterin, N. N. Slyunyaev
Abstract The consistent inclusion of global electric circuit sources of ionospheric and magnetospheric origin in distributed numerical models of the circuit is discussed. It is shown that the most natural approach to this inclusion is to introduce into the boundary conditions at the outer boundary of the model atmosphere the corresponding perturbation of the potential specified up to an unknown constant
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Reconstruction of the Parameters of the Lower Midlatitude Ionosphere in M- and X-Class Solar Flares Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 B. G. Gavrilov, V. M. Ermak, A. N. Lyakhov, Yu. V. Poklad, V. A. Rybakov, I. A. Ryakhovsky
Abstract The paper presents the results of the reconstruction of the effective height h' and the slope of the profile β of the electron concentration in the D layer of the ionosphere during X-ray flares of M- and X-classes at the midlatitudes. The reconstruction was carried out with data from measurements at the observatory of the Institute of Geospheres Dynamics of the Russian Academy of Sciences
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Paleointensity Bursts in the Geomagnetic Field History Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. Yu. Kurazhkovskii, N. A. Kurazhkovskaya, B. I. Klain
Abstract Regularities in the distribution of extreme (burst) increases in paleointensities from 3000 Ma to the present have been studied. Paleointensity bursts that exceed several times its average values Havg have been found to occur over the entire geomagnetic history. The data obtained from thermomagnetized rocks have made it possible to identify variations with characteristic times of 200 Ma in
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Possibility of Diagnostics of the Beginning of Solar Cycle 25 Based on Its Precursors at Mid-Heliolatitudes Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 A. A. Golovko
Abstract The potential to diagnose the beginning of the solar cycle based on the detection of small-scale magnetic formations, the magnetic nodes of ephemeral active regions in the zone of mid-heliolatitudes from 40° to 60°, has been studied. Magnetic nodes were detected at the stage of their emergence by the multifractal segmentation method, which was previously used to fix new magnetic fluxes of
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Ground-Based and Satellite Observations of the SAR Arc in the MLT Evening Sector at the Beginning of the Magnetic Storm on March 17, 2015 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 I. B. Ievenko, S. G. Parnikov
Abstract— Stable auroral red (SAR) arcs are the result of the interaction of energetic ring current ions with the outer plasmasphere (plasmapause). The article analyzes the results of the observation of a SAR arc by an all-sky imager at Maimaga station (58° CGMLat, 202° CGMLon) with the simultaneous detection of the plasmapause and energetic ion fluxes by the Van Allen Probe B (VAP-B) satellite at
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Prolonged, Weak C1.2 Flares: A Source of Protons and Electrons Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 I. Yu. Grigor’eva, A. B. Struminskii, A. N. Shakhovskaya
Abstract Two proton events (>100 MeV; GOES, ACS SPI) associated with weak flares (C1.2, GOES class) in the soft X-ray range that occurred on November 26, 2011, and September 29, 2013, are analyzed. These events were accompanied by significant fluxes of relativistic electrons (>1 MeV; SOHO EPHIN) in the interplanetary space. The time profiles of these protons and electron fluxes were similar during
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Ion Pressure in Different Regions of the Dayside Auroral Precipitation Geomagn. Aeron. (IF 0.461) Pub Date : 2020-12-21 V. G. Vorobjev, O. I. Yagodkina, E. E. Antonova
Abstract The ion pressure in the regions of ionospheric projections of the plasma mantle, polar cusp, low-latitude boundary layer, and the region of structured precipitation of the auroral oval during magnetic calm is studied based on data from the DMSP F6 and F7 low-altitude spacecraft. It is shown that the level of ion pressure in all of these regions does not depend on either the polarity or the
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Calculation of the Ionization Rate in the Atmosphere in the Polar Region during Solar Proton Events Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 E. A. Ginzburg, A. A. Krivolutsky, A. A. Kukoleva, I. N. Myagkova
Abstract— The results of a comparative analysis of the fluxes and spectra of solar protons measured in September 2017 by satellites at different orbits (ELECTRO-L No. 2, GOES 13, and METEOR-3 No. 2) and the results of modeling of the ionization rate in the polar atmosphere based on data from these experiments are presented. It is found based on data from Russian and US satellites that the proton spectra
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Evaluating Solar Quiet Variation of the Horizontal Geomagnetic Field using Nonlinear Time Series Analysis Techniques Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 E. O. Falayi, A. S. Ajose, T. O. Roy-Layinde, A. T. Adewole, J. O. Adepitan
Abstract— In this present paper, the nonlinear time series techniques were used to analyse solar quiet variation in the horizontal component of the geomagnetic field (SqH) data collected from the INTERMAGNET during the year 2012. The complexity of the nonlinear dynamics based on estimated time delay (τ) and embedding dimension (m) are expressed by Lyapunov exponents (LE). The positive values of the
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Reflection of Large Tectonic Structures of the Eastern Part of the Arctic Ocean in the Lithospheric Magnetic Field Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 L. Yu. Abramova, L. M. Abramova, I. M. Varentsov, S. V. Filippov
Abstract The article considers maps of the field of lithospheric magnetic anomalies—images of the deep structures of the Arctic Ocean—constructed from observations by the CHAMP satellite. The lithospheric magnetic anomalies corresponding to the most significant tectonic structures were revealed: Lomonosov Ridge, Mendeleev Ridge, Alpha Rise, and the Amundsen, Podvodnikov and Makarov basins. The distribution
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Ionospheric Disturbances during Meteorological Storms Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 M. I. Karpov, I. V. Karpov, O. P. Borchevkina, G. A. Yakimova, N. A. Korenkova
Abstract Ionospheric disturbances during meteorological storms in the Kaliningrad region with a wind amplification of 8 points or higher on the Beaufort scale for the period 2010–2018 are analyzed. Ionospheric observations made under conditions of low geomagnetic activity are considered. Analysis shows that all of the selected events were accompanied by disturbances of the total electron content (TEC)
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Identification of Vortex Currents in the Ionosphere and Estimation of Their Parameters Based on Ground Magnetic Data Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 V. E. Chinkin, A. A. Soloviev, V. A. Pilipenko
Abstract A system to process data from a 2D network of magnetic stations is proposed for the identification of eddy currents in the ionosphere and the estimation of their parameters. The methodology is applied to an analysis of the structure of daytime traveling convection vortices (TCVs) based on data from Arctic. The problem is solved with optimization methods for various functions obtained via spatial
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Behavior of the Speed and Temperature of the Solar Wind during Interplanetary Disturbances Creating Forbush Decreases Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 A. A. Melkumyan, A. V. Belov, M. A. Abunina, A. A. Abunin, E. A. Eroshenko, V. A. Oleneva, V. G. Yanke
Abstract Forbush decreases of cosmic rays are caused by two types of solar sources: coronal holes and coronal mass ejections. In some cases, the identification of the solar source with the interplanetary disturbance causing the Forbush decrease is difficult and requires a thorough and detailed analysis of the solar-wind characteristics. In these cases, it is useful to compare the behavior of the proton
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Pre-earthquake Atmospheric and Ionospheric Anomalies before Taiwan Earthquakes (M 6.1 and M 6.4) on February (4th and 6th), 2018 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 C. Prasanna Simha, Venkatanathan Natarajan, Katlamudi Madhusudhana Rao
Abstract— Satellite measurements are becoming popular among the scientific community to identify earthquake precursors since its spatial coverage is more and round the clock measurements are possible. In this paper, we analyzed Total Electron Content (TEC), Outgoing Longwave Radiation (OLR), Sea Level Pressure (SLP), Surface Latent Heat flux (SLHF) and Sea Surface Temperature(SST) to identify any abnormal
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Monitoring of the Electron-Acceleration Region with Auroral Kilometric Radiation Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 D. V. Chugunin, A. A. Chernyshov, I. L. Moiseenko, M. E. Viktorov, M. M. Mogilevsky
Abstract A method is proposed for the study of the height–time characteristics of physical processes in the region of auroral electron acceleration. Auroral kilometer radiation, which is generated at the local electron gyrofrequency, can be used to obtain the height distribution of the properties of a radiation source in the auroral region, and long-term satellite measurements of the auroral kilometric
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Evolution of High-Latitude Geomagnetic Disturbances during the Magnetic Storm of July 22, 2009 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 L. I. Gromova, N. G. Kleimenova, S. V. Gromov, L. M. Malysheva
Abstract The behavior of geomagnetic disturbances during a moderate CIR storm, the most intense magnetic storm of 2009 in the solar activity minimum are considered. It is found that the substorm activity during the main phase of the storm was observed not in the nighttime but in the morning sector (0700–0900 MLT) of auroral geomagnetic latitudes (65°–67°) and was accompanied by extremely large (up
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Trends in Parameters of the F 2 Layer and the 24th Solar-Activity Cycle Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 A. D. Danilov, A. V. Konstantinova
Abstract— Trends in foF2 are analyzed according to the data of Juliusruh and Boulder ionospheric stations to 2018. It is shown that the use of the traditional solar-activity index, F10.7, leads to an unexplainable foF2 trend if the data for the 24th solar-activity cycle are included in the analysis. It is suggested that the F10.7 index does not correctly describe the solar ultraviolet-radiation variation
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Tropical Cyclones and Possible Winter Thunderstorms on Kamchatka Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 Yu. M. Mikhailov, S. E. Smirnov, G. A. Mikhailova, O. V. Kapustina
Abstract The influence of tropical cyclones on the thunderstorm activity on the Kamchatka peninsula for winter thunderstorms in the 2008–2018 period is studied. The temporal variations of the quasi-static electric field and meteorological values at the Paratunka Observatory of the Institute of Cosmophysical Research and Radio Wave Propagation (IKIR) of the Far Eastern Branch of the Russian Academy
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Estimation of the Ionospheric Effects of Geomagnetic Disturbances Based on Data from Wakkanai Station Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 A. D. Legen’ka, V. V. Khegai
Abstract Ionosonde measurements of the critical frequency of the ionospheric F2 layer (foF2) at Wakkanai station (Japan) are analyzed with the method of superposed epochs. The station is situated in a region of high seismicity. Winter periods with low sunspot and geomagnetic activity and high seismic activity are considered. The goals of this work were the quantitative characterization and comparison
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Equatorial Plasma Bubbles: Occurrence Probability versus Local Time Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 L. N. Sidorova
Abstract The character of the variability of the LT distributions of the equatorial plasma bubble occurrence probability with an increase of the recording altitude is under consideration. The conditions of the high and maximal solar activity, when the generation of the plasma bubbles is the most active, are examined. For this purpose the detailed comparative analysis of the LT distributions of the
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Effective Solar Activity Index for the Median of the Critical Frequency of the F 2 Layer Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 M. G. Deminov, G. F. Deminova
Abstract—By comparing the moving 12-month averaged values of the F107 solar radiation flux at a wavelength of 10.7 cm and ionospheric solar activity index T, we established the effective solar activity index TF, which is defined as a second-degree polynomial from F107 with coefficients independent of time; it is intended for use in problems of forecasting the median of the critical frequency of the
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Ionospheric Effects of Solar Flares in September 2017 and an Evaluation of Their Influence on Errors in Navigation Measurements Geomagn. Aeron. (IF 0.461) Pub Date : 2020-10-22 I. I. Shagimuratov, I. E. Zakharenkova, N. Yu. Tepenitsina, G. A. Yakimova, I. I. Efishov
Abstract The manifestation of the most powerful flares of class X9.3 and X8.2 recorded on September 6 and 10, 2017, respectively, in the total electronic content (TEC) of the ionosphere, are analyzed. GPS observations at midlatitude stations located in the conditions of an illuminated ionosphere were used as the initial data. The ionospheric response was determined from phase measurements of the TEC
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Long-Term Variations in the Parameters of the Middle and Upper Atmosphere and Ionosphere (Review) Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 A. D. Danilov; A. V. Konstantinova
Abstract—The article reviews the main publications from the last eight years on long-term trends in the parameters of the middle atmosphere, thermosphere, and ionosphere. It is shown that the negative temperature trends in the middle atmosphere have been reliably established based on observations by various methods. An analysis of satellite orbits in the thermosphere showed negative density trends
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Analytical Model of a Seismogenic Electric Field According to Data of Measurements in the Surface Layer of the Midlatitude Atmosphere and Calculation of Its Magnitude at the Ionospheric Level Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 V. V. Khegai
AbstractPerturbations of the vertical component of an electric field of seismogenic origin near the Earth’s surface prior to some earthquakes are modeled analytically based on data from measurements in the surface layer of the atmosphere at midlatitudes, and the field’s magnitude at the ionospheric level is calculated with allowance for the inclination of geomagnetic lines of force. An analytical approximation
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Role of the Outer Ionosphere in the Winter/Summer Asymmetry of Auroral Electron Precipitations Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 M. G. Deminov
AbstractThis paper analyzes the role of the outer ionosphere in the occurrence of a large difference in the frequency of accelerated electron fluxes in the auroral region in the premidnight sector for winter and summer conditions, which are associated with discrete auroras. Simulation indicates that the critical value JEIC of the longitudinal current of the Alfvén wave for the development of electrostatic
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Variation of Plasma Pressure at the Auroral Oval Latitudes before, during, and after the Isolated Geomagnetic Substorm on December 22, 2008 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 M. Rojas Gamarra; J. Gonzalez; M. V. Stepanova; E. E. Antonova
AbstractThe change in plasma pressure at the latitudes of the auroral oval before, during, and after the isolated geomagnetic substorm on December 22, 2008, were studied using data from the F13, 15, 16, and 17 DMSP satellites. One feature of the studied event was a long period of values of AL index that were close to zero. During this time, there was a more than double increase in the dynamic pressure
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Characteristics of the Growth Increment of Drift-Dissipative Instability at the Fronts of Equatorial Plasma Bubbles Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 N. M. Kashchenko; M. A. Nikitin
AbstractData from ground-based and satellite measurements, as well as the results of numerical modeling of the spatial structure of equatorial ionospheric bubbles, show that the longitude gradients of the logarithm of the electron concentration at the vertical boundaries of the bubbles can reach 10–3 m–1. At such electron concentration gradients, the development of drift-dissipative instability is
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Ionospheric Disturbances due to the Influence of Localized Thermospheric Sources Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 I. V. Karpov; P. A. Vasiliev
AbstractThe paper presents the results of numerical modeling of the ionospheric disturbances from spatially localized, midlatitude, thermospheric sources that simulate the dissipation effect of acoustic–gravity waves generated by phenomena on the Earth’s surface and in the lower atmosphere. The results of numerical calculations have shown that the range of ionospheric effects significantly exceeds
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Formation and Evolutionary Changes of Coronal Holes in the Growth Phase of Cycle 23 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 I. A. Bilenko; K. S. Tavastsherna
AbstractThe regularities in the formation of coronal holes in the growth phase of cycle 23 are studied. The period from January 1, 1997, to March 1, 2000 (Carrington rotations 1918–2059), is considered in detail. The evolution of the global magnetic field of the Sun from a zonal to a sectorial structure of the field distribution is analyzed. The zonal structure is shown to be quasi-stable. The sum
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Characteristics of the Energy Transfer by Alfvén Waves in the Solar Atmosphere Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 Yu. T. Tsap; A. V. Stepanov; Yu. G. Kopylova; O. V. Khaneichuk
AbstractThe propagation of linear Alfvén waves with periods of 10–200 s from the photosphere to the solar chromosphere under the conditions of an isothermal atmosphere taking into account the amplitude-phase relationships are considered. It was found that the amplitude of the wave velocity perturbation increases and the magnetic field perturbation decreases with increasing height, while the phase difference
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Comparison of the Intensity of the Nighttime Scattered Atmospheric Radiation in the Lyman-Alpha Line from OGO-4 Satellite Measurements and Calculations Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 A. V. Pavlov; N. M. Pavlova
AbstractA theoretical model has been developed for the calculation of the intensity and flux of nighttime Lyman-alpha solar radiation at altitudes of the atmosphere that takes into account the multiple scatterings of this radiation by atmospheric atomic hydrogen. At heights of more than two Earth radii, the number density of atomic hydrogen is calculated by an empirical model based on the agreement
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Color of the Corona Continuum of July 11, 1991 Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 I. S. Kim; N. L. Krusanova; V. V. Popov; A. R. Osokin; I. V. Mironova
AbstractThe color of the coronal continuum was determined from observations in order to search for manifestations of coronal expansion. A brief review of studies determining the color of the coronal continuum finds that the previously obtained results are inconsistent. The color index for the coronal continuum is defined. The necessity of the use of a relative color index is substantiated. RCI estimates
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Characteristics of the Pitch-Angle Anisotropy of Energetic Protons in the Daytime Magnetosphere due to Particle Drift in the Nondipole Magnetic Field Geomagn. Aeron. (IF 0.461) Pub Date : 2020-08-18 A. A. Lyubchich; A. G. Demekhov; A. G. Yahnin
Abstract—This paper analyzes the effect of azimuthal proton drift from the nighttime sector of the Earth’s magnetosphere on the characteristics of the pitch-angle anisotropy of proton fluxes in the daytime sector. The drift in the magnetic field caused by curvature of the field lines and the magnetic field gradient, in the absence of external forces, has been considered. The external geomagnetic field
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