scholarly journals A quantitative assessment of empirical magnetic field models at geosynchronous orbit during magnetic storms

2008 ◽  
Vol 113 (A4) ◽  
pp. n/a-n/a ◽  
Author(s):  
Chia-Lin Huang ◽  
Harlan E. Spence ◽  
Howard J. Singer ◽  
Nikolai A. Tsyganenko
Keyword(s):  
Magnetic Field ◽  
Quantitative Assessment ◽  
Magnetic Storms ◽  
Geosynchronous Orbit

The Geosynchronous Substorm

1996 ◽  
Author(s):  
Charles F. Kennel
Keyword(s):  
Magnetic Field ◽  
Growth Phase ◽  
Large Scale ◽  
Current System ◽  
Dynamic Pressure ◽  
Geosynchronous Orbit ◽  
Sudden Increase ◽  
Tail Current ◽  
Tightly Coupled ◽  
The Cross

The reconnection model of substorms deals with the large-scale changes in the structure of the magnetosphere and tail as convection intensifies following a sudden increase in the dayside reconnection rate. The model has difficulty making statements relevant to the small scales that characterize auroral onset. However, there has been considerable progress in assembling high-resolution observations of the events in space that now appear to be tightly coupled to the dramatic auroral events that first defined the term substorm. We will call this clear and consistent ensemble the geosynchronous model of substorms, since most of it was first conceived from observations made on geostationary spacecraft. We will also include in this ensemble the recent observations made using the quasigeostationary spacecraft, AMPTE/CCE, and so, by the geosynchronous substorm, we really mean the substorm as it appears on the earth's nightside typically between 6 and, say, 10 RE downtail. The earth’s magnetic field at geosynchronous orbit is about 100 nT, some three times larger than in the tail lobes. Study of quiet field intervals singles out the dependence of the geosynchronous field on solar wind dynamic pressure, since the modulation due to changes in the direction of the interplanetary field is presumably negligible during quiet conditions. The periodic variations in the quiet field depend on local time, season, and orientation of the earth’s dipole axis relative to spacecraft location (McPherron and Barfield, 1980; Rufenach et al., 1992). Superposed on the quiet field are perturbations up to about 50 nT due to several magnetospheric current systems, including the magnetopause current, the ring current, and the cross-tail current; the most striking are due to changes in the cross-tail current system. Observations from geosynchronous orbit were the first to indicate that the nightside magnetic field becomes more “tail-like” during substorm growth phase, and more dipolar during the expansion phase. This simple observation is the foundation on which today’s elaborate geosynchronous substorm model rests. The geosynchronous field becomes progressively more “tail-like” as the cross-tail current system intensifies and/or moves earthward during the substorm growth phase (McPherron et al., 1975; Coleman and McPherron, 1976; McPherron, 1979; Kauffmann, 1987).

scholarly journals The relativistic electron response in the outer radiation belt during magnetic storms

2002 ◽  
Vol 20 (7) ◽  
pp. 957-965 ◽  
Author(s):  
R. H. A. Iles ◽  
A. N. Fazakerley ◽  
A. D. Johnstone ◽  
N. P. Meredith ◽  
P. Bühler
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Wind Speed ◽  
Interplanetary Magnetic Field ◽  
Relativistic Electron ◽  
Radiation Belt ◽  
Solar Wind Speed ◽  
Recovery Phase ◽  
Magnetic Storms ◽  
Outer Radiation Belt

Abstract. The relativistic electron response in the outer radiation belt during magnetic storms has been studied in relation to solar wind and geomagnetic parameters during the first six months of 1995, a period in which there were a number of recurrent fast solar wind streams. The relativistic electron population was measured by instruments on board the two microsatellites, STRV-1a and STRV-1b, which traversed the radiation belt four times per day from L ~ 1 out to L ~ 7 on highly elliptical, near-equatorial orbits. Variations in the E > 750 keV and E > 1 MeV electrons during the main phase and recovery phase of 17 magnetic storms have been compared with the solar wind speed, interplanetary magnetic field z-component, Bz , the solar wind dynamic pressure and Dst *. Three different types of electron responses are identified, with outcomes that strongly depend on the solar wind speed and interplanetary magnetic field orientation during the magnetic storm recovery phase. Observations also confirm that the L-shell, at which the peak enhancement in the electron count rate occurs has a dependence on Dst *.Key words. Magnetospheric physics (energetic particles, trapped; storms and substorms) – Space plasma physics (charged particle motion and accelerations)

Variations of electrical characteristics of near-surface atmosphere of the Earth during magnetic storm

2020 ◽  
Author(s):  
Svetlana Riabova ◽  
Alexander Spivak
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Magnetic Storms ◽  
Electrical Characteristics ◽  
Near Surface ◽  
Russian Academy Of Sciences ◽  
The Earth ◽  
Geosphere Dynamics ◽  
Academy Of Sciences ◽  
The Magnetic Field

<p>Temporal variations of the electric field in near-surface layer of the Earth are determined by many factors, among which strong disturbances of the magnetic field should be especially noted. Magnetic storms cause an increase in the ionospheric electric field, which leads to variations in the gradient of the electric field potential near the Earth's surface. We consider the effect of magnetic storms in variations in the electrical characteristics of the atmosphere at Geophysical observatory «Mikhnevo» of Sadovsky Institute of Geosphere Dynamics of Russian Academy of Sciences and at Center for geophysical monitoring of Moscow of Sadovsky Institute of Geosphere Dynamics of Russian Academy of Sciences. We used data from the continuous monitoring of three components of the magnetic field, vertical components of the atmospheric electric field and atmospheric current carried out in fair weather. Experimental data processing and analysis show that accompanying magnetic storms with geomagnetic K index more or equal 5 increased variations in the electric field and vertical atmospheric current are characterized by different morphological structures. It is currently difficult to interpret the data. Nevertheless, the research results can be of great help in the development and verification of theoretical and computational models for generating variations in the electric field as a result of strong geomagnetic disturbances.</p>

scholarly journals Interrelation between the content of magnesium in the blood of the strain stenocardia patients of different temperament and anxiety and tension degree of the Earth magnetic field

2014 ◽  
Vol 21 (2) ◽  
pp. 46-50
Author(s):  
G. A. Usenko ◽  
A. G. Usenko ◽  
D. V. Vasendin ◽  
N. A. Schakirova
Keyword(s):  
Magnetic Field ◽  
At Risk ◽  
Coronary Heart Disease ◽  
Heart Disease ◽  
Angina Pectoris ◽  
Magnesium Content ◽  
Magnetic Storms ◽  
The Earth ◽  
Earth Magnetic Field

During the magnetic storms magnesium content decreases and frequency of angina pectoris attacks increases minimally in the lowanxiety cholerics and maximally in the highanxiety melancholics and phlegmatics. The latter are the groups at risk of developing complications of coronary heart disease.

scholarly journals How Space Storms Affect the Satellite Superhighway

Eos ◽  
2018 ◽  
Vol 99 ◽  
Author(s):  
Emily Underwood
Keyword(s):  
Magnetic Field ◽  
Numerical Model ◽  
Space Weather ◽  
Geosynchronous Orbit

A powerful numerical model reveals how space weather disturbs magnetic field at geosynchronous orbit.

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