Earth's ionosphere

Theory and phenomenology of cowling channels

Akimasa Yoshikawa, Ryoichi Fujii

研究成果: 著書/レポートタイプへの貢献

抄録

The Cowling channel is a generic name of a current system forming inside a high conductivity band in which a secondary polarization electric field modifies the current flow. The polarization field is excited when a divergent part of Hall current driven by the primary electric field is prevented from flowing out to the magnetosphere as the field-aligned current. The purpose of this chapter is to review the recent development of the Cowling channel model. Recent work provides an extension of the theoretical description of the classical Cowling channel with respect to the following aspects: (1) taking into account the 3D nature of the ionosphere by introducing two current layers at different altitudes, and (2) considering finite length of the Cowling channel by introducing a conductance boundary not only at the meridional borders of the Cowling channel, but also at its zonal boundaries. Using this improved model, we discuss current closure and the energy principle for evolution of the Cowling channel. Energy flow inside the Cowling channel and impact of the polarization effect on Joule dissipation in the more general M-I coupling scheme are also provided. We also clarify how shear Alfvén waves interact to the Cowling channel and their application to the global magnetosphere- ionosphere coupling simulations.

元の言語英語
ホスト出版物のタイトルElectric Currents in Geospace and Beyond
出版者wiley
ページ427-443
ページ数17
ISBN(電子版)9781119324522
ISBN(印刷物)9781119324492
DOI
出版物ステータス出版済み - 4 17 2018

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Ionosphere
electric field
Names
Magnetosphere
Earth (planet)
Polarization
energy flow
Electric fields
shears
Shear waves
energy
Earth ionosphere

All Science Journal Classification (ASJC) codes

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Medicine(all)

これを引用

Yoshikawa, A., & Fujii, R. (2018). Earth's ionosphere: Theory and phenomenology of cowling channels. : Electric Currents in Geospace and Beyond (pp. 427-443). wiley. https://doi.org/10.1002/9781119324522.ch25

Earth's ionosphere : Theory and phenomenology of cowling channels. / Yoshikawa, Akimasa; Fujii, Ryoichi.

Electric Currents in Geospace and Beyond. wiley, 2018. p. 427-443.

研究成果: 著書/レポートタイプへの貢献

Yoshikawa, A & Fujii, R 2018, Earth's ionosphere: Theory and phenomenology of cowling channels. : Electric Currents in Geospace and Beyond. wiley, pp. 427-443. https://doi.org/10.1002/9781119324522.ch25
Yoshikawa A, Fujii R. Earth's ionosphere: Theory and phenomenology of cowling channels. : Electric Currents in Geospace and Beyond. wiley. 2018. p. 427-443 https://doi.org/10.1002/9781119324522.ch25
Yoshikawa, Akimasa ; Fujii, Ryoichi. / Earth's ionosphere : Theory and phenomenology of cowling channels. Electric Currents in Geospace and Beyond. wiley, 2018. pp. 427-443
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