Whistler observations of magnetospheric electric field in the night side plasma-sphere at low latitude

1982 ◽  
Vol 27 (4) ◽  
pp. 453-462 ◽  
Author(s):  
P. N. Khosa ◽  
M. M. Ahmad ◽  
Lal Mani
Keyword(s):  
Electric Field ◽  
Low Latitude ◽  
Plasma Sphere ◽  
Night Side

scholarly journals Identification of the mechanisms responsible for anomalies in the tropical lower thermosphere/ionosphere caused by the January 2009 sudden stratospheric warming

2019 ◽  
Vol 9 ◽  
pp. A39 ◽  
Author(s):  
Maxim V. Klimenko ◽  
Vladimir V. Klimenko ◽  
Fedor S. Bessarab ◽  
Timofei V. Sukhodolov ◽  
Pavel A. Vasilev ◽  
...  
Keyword(s):  
Electric Field ◽  
Phase Change ◽  
Lower Thermosphere ◽  
Upper Atmosphere ◽  
Electron Content ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Low Latitude ◽  
Plasma Drift ◽  
Solar Tide

We apply the Entire Atmosphere GLobal (EAGLE) model to investigate the upper atmosphere response to the January 2009 sudden stratospheric warming (SSW) event. The model successfully reproduces neutral temperature and total electron content (TEC) observations. Using both model and observational data, we identify a cooling in the tropical lower thermosphere caused by the SSW. This cooling affects the zonal electric field close to the equator, leading to an enhanced vertical plasma drift. We demonstrate that along with a SSW-related wind disturbance, which is the main source to form a dynamo electric field in the ionosphere, perturbations of the ionospheric conductivity also make a significant contribution to the formation of the electric field response to SSW. The post-sunset TEC enhancement and pre-sunrise electron content reduction are revealed as a response to the 2009 SSW. We show that at post-sunset hours the SSW affects low-latitude TEC via a disturbance of the meridional electric field. We also show that the phase change of the semidiurnal migrating solar tide (SW2) in the neutral wind caused by the 2009 SSW at the altitude of the dynamo electric field generation has a crucial importance for the SW2 phase change in the zonal electric field. Such changes lead to the appearance of anomalous diurnal variability of the equatorial electromagnetic plasma drift and subsequent low-latitudinal TEC disturbances in agreement with available observations. Plain Language Summary – Entire Atmosphere GLobal model (EAGLE) interactively calculates the troposphere, stratosphere, mesosphere, thermosphere, and plasmasphere–ionosphere system states and their response to various natural and anthropogenic forcing. In this paper, we study the upper atmosphere response to the major sudden stratospheric warming that occurred in January 2009. Our results agree well with the observed evolution of the neutral temperature in the upper atmosphere and with low-latitude ionospheric disturbances over America. For the first time, we identify an SSW-related cooling in the tropical lower thermosphere that, in turn, could provide additional information for understanding the mechanisms for the generation of electric field disturbances observed at low latitudes. We show that the SSW-related vertical electromagnetic drift due to electric field disturbances is a key mechanism for interpretation of an observed anomalous diurnal development of the equatorial ionization anomaly during the 2009 SSW event. We demonstrate that the link between thermospheric winds and the ionospheric dynamo electric field during the SSW is attained through the modulation of the semidiurnal migrating solar tide.

scholarly journals The Acceleration of Outer-Belt Electrons by Localized Electric Fields

2021 ◽  
Vol 61 (4) ◽  
pp. 477-482
Author(s):  
A. P. Kropotkin
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Relativistic Electrons ◽  
Strong Component ◽  
Short Term ◽  
Energetic Electrons ◽  
Geomagnetic Tail ◽  
Night Side ◽  
Bursty Bulk Flows

Abstract To explain the populations of the outer-belt energetic electrons, including relativistic electrons, that sporadically appear in the magnetosphere, a mechanism was proposed long ago for the acceleration of those electrons by short-term bursts of the electric field, which appear on the night side during substorm disturbances (Kropotkin, 1996). This mechanism can be substantially specified if the modern concepts of bursty bulk flows in the geomagnetic tail, the occurrence of dipolarization fronts, and the excitation of localized field-aligned-resonant poloidal Alfvén oscillations involving a strong component of the electric field in the dawn-dusk direction are taken into account.

scholarly journals Evidence for the interplanetary electric field effect on the OI 630.0 nm airglow over low latitude

2005 ◽  
Vol 110 (A11) ◽  
Author(s):  
D. Chakrabarty ◽  
R. Sekar ◽  
R. Narayanan ◽  
C. V. Devasia ◽  
B. M. Pathan
Keyword(s):  
Electric Field ◽  
Field Effect ◽  
Electric Field Effect ◽  
Low Latitude

scholarly journals ANALISIS PENGARUH PENETRASI MEDAN LISTRIK LINTANG TINGGI KE LINTANG RENDAH TERHADAP IONOSFER SAAT BADAI GEOMAGNET (ANALYSIS OF THE ELECTRIC FIELD PENETRATION EFFECT FROM HIGH TO LOW LATITUDES ON THE IONOSPHERE DURING GEOMAGNETIC STORM)

2018 ◽  
Vol 14 (2) ◽  
pp. 97
Author(s):  
Anwar Santoso ◽  
Dadang Nurmali ◽  
Mira Juangsih ◽  
Iyus Edi Rusnadi ◽  
Sri Ekawati ◽  
...  
Keyword(s):  
Electric Field ◽  
Electric Current ◽  
High Latitude ◽  
Delay Time ◽  
Geomagnetic Storms ◽  
Equatorial Electrojet ◽  
Minimum Point ◽  
Low Latitude ◽  
Dst Index ◽  
Low Latitudes

The influence of geomagnetic storms on the ionosphere in the equatorial and low latitudes can be either rising or falling value of the value foF2 with the different response delay time. The difference in response is one of them allegedly influenced by the modification of Equatorial Electrojet (EEJ) generated by the penetration of high latitude electric field towards the low latitude electric field and the equator. Therefore, this paper analyzes the influence of the high latitude penetration of electric current to the low latitude electric current towards the ionosphere response to Indonesia's current geomagnetic storms using the data foF2 BPAA Sumedang (SMD; 6,910 S; 106,830E geographic coordinates or 16,550 S; 179,950 E magnetic coordinates) and data from the Biak geomagnetic field station (BIK; 1,080 S; 136,050 E geographic coordinates or  9,730 S; 207,390 E magnetic coordinates) in 2000-2001. The result showed that the injection of the electric field of the high latitudes to lower latitudes causing foF2 BPAA Sumedang to be disturbed. Onset of the foF2 disturbance in BPAA Sumedang started coincide with EEJ(HBIK-HDRW) and reached its minimum point with a time delay between 0 to 4 hours before and after Dst index reached the minimum point. For a delay time of 0 to 4 hours after the Dst index reached the minimum point, the results were in accordance with the research results from the prior research. However, for the time difference of between 0 to 4 hours before the Dst index reached the minimum point, the results differ from their results. AbstrakPengaruh badai geomagnet terhadap ionosfer di ekuator dan lintang rendah berupa naiknya nilai foF2 atau turunnya nilai foF2 dengan waktu tunda respon berbeda-beda. Perbedaan respon tersebut salah satunya diduga dipengaruhi oleh modifikasi Equatorial electrojet (EEJ) yang dihasilkan oleh penetrasi medan listrik lintang tinggi sampai daerah lintang rendah dan ekuator. Oleh karena itu, dalam makalah ini dilakukan analisis pengaruh penetrasi arus listrik lintang tinggi ke lintang rendah terhadap ionosfer saat badai geomagnet menggunakan data foF2 dari Balai Pengamatan Antariksa dan Atmosfer (BPAA) Sumedang (SMD; 6,910 LS; 106,830 BT koordinat geografis atau 16,550 LS; 179,950 BT koordinat magnet) dan data medan geomagnet dari stasiun Biak (BIK; 1,080 LS; 136,050 BT koordinat geografis atau 9,730 LS; 207,390 BT koordinat magnet) tahun 2000-2001. Hasilnya diperoleh bahwa penetrasi medan listrik dari lintang tinggi ke lintang lebih rendah Indonesia menyebabkan foF2 BPAA Sumedang terganggu. Onset gangguan foF2 BPAA Sumedang mulai terjadi bertepatan dengan EEJ(HBIK-HDRW) mencapai titik minimumnya dengan jeda waktu antara 0 sampai 4 jam sebelum dan sesudah indeks Dst mencapai minimum. Untuk beda waktu 0 sampai 4 jam sesudah indeks Dst mencapai minimum, hasilnya bersesuaian dengan hasil penelitian peneliti sebelumnya. Namun, untuk beda waktu 0 sampai 4 jam sebelum indeks Dst mencapai minimum, hasilnya merupakan temuan berbeda dari hasil mereka.

scholarly journals Zonal/meridional wind and disturbance dynamo electric field control of the low-latitude ionosphere based on the SUNDIAL/ATLAS 1 Campaign

1996 ◽  
Vol 101 (A12) ◽  
pp. 26729-26740 ◽  
Author(s):  
M. A. Abdu ◽  
J. H. A. Sobral ◽  
P. Richards ◽  
Marta M. de Gonzalez ◽  
Y. N. Huang ◽  
...  
Keyword(s):  
Electric Field ◽  
Meridional Wind ◽  
Low Latitude ◽  
Field Control ◽  
Low Latitude Ionosphere

A review of the October 21, 1989 red aurora seen in Japan and from the AKEBONO (EXOS-D) satellite

1992 ◽  
Vol 70 (7) ◽  
pp. 488-499 ◽  
Author(s):  
T. Oguti
Keyword(s):  
Electric Field ◽  
Magnetic Storm ◽  
Auroral Oval ◽  
Low Latitude ◽  
Terrestrial Environment ◽  
Acceleration Mechanism ◽  
Auroral Substorm ◽  
Field Fluctuations ◽  
The Difference ◽  
Auroral Expansion

Observations of the October 21, 1989 red aurora from the ground and AKEBONO satellite are reviewed mainly on the topics presented at the workshop on the aurora, held in Solar Terrestrial Environment Laboratory on January 17–18, 1991. Electric-field fluctuations associated with the auroral oval during the observation, together with auroral green-rayed structures embedded in the red veil strongly suggest that some electron acceleration mechanism was operative in the particle precipitation. Therefore this was not a typical stable auroral red (SAR) arc. This red aurora was most likely located at a low-latitude portion of an expansion aurora during an auroral substorm. The geomagnetic conditions at the time of the aurora were quite similar to those during the occurrence of a SAR arc. It occurred during a susbtorm that broke out at the maximum Dst (disturbance with storm time) phase of a magnetic storm, with an auroral expansion initiated from low latitude on a well-expanded auroral oval. The difference in conditions between a typical SAR arc and this red aurora with green-ray structures is to be studied further.

scholarly journals Modification of conductivity due to acceleration of the ionospheric medium

2008 ◽  
Vol 26 (8) ◽  
pp. 2111-2130 ◽  
Author(s):  
V. V. Denisenko ◽  
H. K. Biernat ◽  
A. V. Mezentsev ◽  
V. A. Shaidurov ◽  
S. S. Zamay
Keyword(s):  
Magnetic Field ◽  
Field Line ◽  
Electric Current ◽  
Magnetic Field Line ◽  
Conducting Layer ◽  
Low Latitude ◽  
Ionosphere Model ◽  
Zero Current ◽  
Night Side ◽  
Low Latitude Ionosphere

Abstract. A quantitative division of the ionosphere into dynamo and motor regions is performed on the base of empirical models of space distributions of ionospheric parameters. Pedersen and Hall conductivities are modified to represent an impact of acceleration of the medium because of Ampére's force. It is shown that the currents in the F2 layer are greatly reduced for processes of a few hours duration. This reduction is in particular important for the night-side low-latitude ionosphere. The International Reference Ionosphere model is used to analyze the effect quantitatively. This model gives a second high conducting layer in the night-side low-latitude ionosphere that reduces the electric field and equatorial electrojets, but intensifies night-side currents during the short-term events. These currents occupy regions which are much wider than those of equatorial electrojets. It is demonstrated that the parameter σd=σP+σHΣH/ΣP that involves the integral Pedersen and Hall conductances ΣP, ΣH ought to be used instead of the local Cowling conductivity σC in calculations of the electric current density in the equatorial ionosphere. We may note that Gurevich et al. (1976) derived a parameter similar to σd for more general conditions as those which we discuss in this paper; a more detailed description of this point is given in Sect. 6. Both, σd and σC, appear when a magnetic field line is near a nonconducting domain which means zero current through the boundary of this domain. The main difference between σd and σC is that σd definition includes the possibility for the electric current to flow along a magnetic field line in order to close all currents which go to this line from neighboring ones. The local Cowling conductivity σC corresponds to the current closure at each point of a magnetic field line. It is adequate only for a magnetic field line with constant local conductivity at the whole line when field-aligned currents do not exist because of symmetry, but σC=σd in this case. So, there is no reason to use the local Cowling conductivity while the Cowling conductance ΣC=ΣP+ΣH2/ΣP is a useful and well defined parameter.

scholarly journals Magnetospheric response to the interaction with the sporadic solar wind diamagnetic structure

2021 ◽  
Vol 7 (3) ◽  
pp. 11-28
Author(s):  
Vladimir Parkhomov ◽  
Viktor Eselevich ◽  
Maxim Eselevich ◽  
Alexei Dmitriev ◽  
Alla Suvorova ◽  
...  
Keyword(s):  
Solar Wind ◽  
Electric Field ◽  
Classical Model ◽  
Ion Concentration ◽  
The Sun ◽  
Large Size ◽  
The Earth ◽  
Night Side ◽  
Mass Ejection ◽  
Deep Modulation

We report the results of a study on the movement of the solar wind diamagnetic structure (DS), which is a sequence of smaller-scale microDS being part of the May 18, 2013 coronal mass ejection, from a source on the Sun to Earth’s surface. DS determined from the high negative correlation coefficient (r=–0.9) between the IMF modulus (B) and the SW density (N) on the ACE and Wind satellites at the L1 point, on the THB and THC satellites (r=–0.9) in near-Earth orbit, and on the THA satellite inside the magnetosphere is carried by the solar wind from the Sun to Earth’s orbit, while maintaining its fine internal structure. Having a large size in the radial direction (≈763 Rᴇ, where Rᴇ is the Earth radius), DS flows around the magnetosphere. At the same time, microDS of size ≤13 Rᴇ passes through the bow shock and magnetopause as a magnetized plasmoid in which the ion concentration increases from 10 cm⁻³ to 90 cm⁻³, and the velocity decreases as it moves toward the magnetotail. When a microDS passes through the magnetopause, a pulsed electric field of ~400 mV/m is generated with subsequent oscillations with a period of T~200 s and an amplitude of ~50 mV/m. The electric field accelerates charged particles of the radiation belt and produces modulated fluxes of protons in an energy range 95–575 keV on the day side and electrons in 40–475 keV and protons in 95–575 keV on the night side. In the duskside magnetosphere (19–23 MLT), the substorm activation is observed in geomagnetic pulsations and auroras, but without a magnetic negative bay. In the post-midnight sector (01–05 MLT), a sawtooth substorm occurs without the growth phase and breakup with deep modulation of the ionospheric current and auroral absorption. The duration of all phenomena in the magnetosphere and on Earth is determined by the period of interaction between DS and the magnetosphere (~4 hrs). To interpret the regularities of the magnetospheric response to the interaction with DS, we consider alternative models of the impulsive passage of DS from SW to the magnetosphere and the classical model of reconnection of IMF and the geomagnetic field.

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