One of the CDAW 9C substorms is investigated in this paper using database reported by Hones et al. and supplemented with magnetogram inversion technique (MIT) 2 data. These latter have provided information about dynamics open tail magnetic flux, current systems ionosphere, size wedge. We identified growth, expansion, recovery phases substorm, characteristics expected from a generally accepted scenario. However, specific signatures were observed interval (0919‐0935) UT, i.e., between growth...

Abstract We supplement the results of 27 August 2001 substorm studied earlier in series papers. Described is plasma flow nightside ionosphere from near‐polar region polar cap to auroral oval during preonset phase and two expansion onsets, EO1 EO2, produced by reconnection closed tail (magnetic (MR1) open lobes (MR2), respectively. discuss location MR2 (is it near, middle, and/or distant tail?) EO2 trigger mechanism. The upward current wedge field‐aligned (FAC) downward FAC dusk sector that...

The distribution of field-aligned currents (FAC) during quiet and disturbed periods is calculated with the Magnetogram Inversion Technique (MIT). polar cap boundary determined as high-latitude region 1 FAC. Statistical results on location size obtained from MIT are compared those two independent methods: one based Viking auroral images other mapping using Tsyganenko 1987 magnetic field model. three methods yield essentially same results. northern shifted towards dawn or dusk, depending sign...

It is shown that the convection reversal boundary a fundamental parameter of magnetosphere-ionosphere coupling, which determines strong analogy between electrostatic potential ionosphere and equivalent current function in dipole geomagnetic field approximation uniform ionospheric conductance. We have developed new ground-based method for automatically diagnosing boundaries auroral oval using output data obtained with magnetogram inversion technique (MIT). Using maps field-aligned currents,...

The magnetogram inversion technique (MIT), developed at ISTP SB RAS more than forty years ago, has been used until recently only in the Northern Hemisphere. In recent years, MIT improved and extended to make instantaneous calculations of 2D distributions electric fields, horizontal field-aligned currents two polar ionospheres. were carried out based on one-minute ground-based geomagnetic measurements from worldwide network stations both hemispheres (SuperMAG). this paper, is approximation...

We report on strong induction effects notably contributing to the cross polar cap potential drop and energy balance during growth active phases of substorm 27 August 2001. The inductance magnetosphere is found be crucial for electrical features in course substorm. inductive response switching off solar wind-magnetosphere generator exceeds effect interplanetary magnetic field (IMF) variation. are most apparent expansion onset when rapid ionospheric conductivity accompanied by fast release...

It is shown that the convection reversal boundary a fundamental parameter of magnetosphere-ionosphere coupling, which determines strong analogy between electrostatic potential ionosphere and equivalent current function in dipole geomagnetic field approximation uniform ionospheric conductance. We have developed new ground-based method for automatically diagnosing boundaries auroral oval using output data obtained with magnetogram inversion technique (MIT). Using maps field-aligned currents,...

A study of intensities large-scale spatial distributions dayside and nightside field-aligned currents (FAC), obtained using the magnetogram inversion technique (MIT) from ground-based magnetometers, during period stationary magnetospheric convection (SMC) on September 24, 1998 is presented. Quantitative qualitative analysis showed that SMC there was a monotonic increase quasi-equilibrium between FACs region 1, while in intensity FAC began before SMC, substorm; end decrease observed.

The ground-based automatic method for determining auroral oval (AO) boundaries developed by the authors [Lunyushkin, Penskikh, 2019] has been modified and expanded to Southern Hemisphere. Input data of contains large-scale distributions equivalent current function field-aligned density calculated in polar ionospheres two hemispheres a uniform ionospheric conductance approximation based on magnetogram inversion technique geomagnetic database world network stations SuperMAG project. software...

We analyze significant increases in 630 nm atomic oxygen night emissions during very strong geomagnetic storms, using optical measurements, theoretical modeling, and magnetogram inversion technique (MIT) data. It is shown that magnetic storms when electron precipitation equatorial boundary at the sector expands up to ~40°, interaction of energetic flux with thermospheric components may cause extreme emission intensity. Model calculations red line intensity show good agreement observational...

We continue to study the physical processes occurring during August 17, 2001 magnetospheric storm by analyzing dynamics of intensity field-aligned currents (FACs) in Iijima—Potemra Region 1 polar ionospheres two hemispheres, using modernized magnetogram inversion technique. The results obtained on types FAC asymmetry (dawn-dusk and interhemispheric), as well previously regularities behavior Hall cap boundaries depending large azimuthal component interplanetary magnetic field (IMF), observed...

The ground-based automatic method for determining auroral oval (AO) boundaries developed by the authors [Lunyushkin, Penskikh, 2019] has been modified and expanded to Southern Hemisphere. Input data of contains large-scale distributions equivalent current function field-aligned density calculated in polar ionospheres two hemispheres a uniform ionospheric conductance approximation based on magnetogram inversion technique geomagnetic database world network stations SuperMAG project. software...

Based on the output data of magnetogram inversion technique, we analyze dynamics Pedersen ionospheric currents and field-aligned (FACs) in night mesoscale cells three main large-scale Iijima Potemra Regions (R1, R2 R0) during expansion phase summer winter substorms. FACs play a key role ionosphere-magnetosphere interaction. The continuity equation for electric current density contains two types possible feedback within circuit parts that connect each cell. conductivity is dominant to Type 1,...

The magnetogram inversion technique (MIT), developed at ISTP SB RAS more than forty years ago, has been used until recently only in the Northern Hemisphere. In recent years, MIT improved and extended to make instantaneous calculations of 2D distributions electric fields, horizontal field-aligned currents two polar ionospheres. were carried out based on one-minute ground-based geomagnetic measurements from worldwide network stations both hemispheres (SuperMAG). this paper, is approximation...