日本地球惑星科学連合2024年大会

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[E] 口頭発表

セッション記号 P (宇宙惑星科学) » P-EM 太陽地球系科学・宇宙電磁気学・宇宙環境

[P-EM10] Dynamics of Magnetosphere and Ionosphere

2024年5月27日(月) 09:00 〜 10:15 展示場特設会場 (2) (幕張メッセ国際展示場 6ホール)

コンビーナ:今城 峻(京都大学大学院理学研究科附属地磁気世界資料解析センター)、家田 章正(名古屋大学 宇宙地球環境研究所)、佐藤 由佳(日本工業大学)、藤本 晶子(九州工業大学)、座長:門倉 昭(国立極地研究所)、今城 峻(京都大学大学院理学研究科附属地磁気世界資料解析センター)

09:00 〜 09:15

[PEM10-01] Observations of solar wind-magnetosphere-ionosphere coupling and its impact on equatorial ionospheric electrodynamics

*Guan Le1、Guiping Liu1、Endawoke Yizengaw2 (1.NASA Goddard Space Flight Center、2.The Aerospace Corporation)

キーワード:solar wind-magnetosphere-ionosphere coupling, magnetic storms, field-aligned currents, equatorial electrojet, equatorial ionospheric electrodynamics , MI Coupling

The low-latitude ionosphere is effectively shielded from the high latitude convection electric field during geomagnetic quiet times because region-2 field-aligned currents associated with the partial ring current act to oppose the convection electric field associated with region-1 field-aligned currents. However, the low-latitude ionosphere can be directly coupled to the enhanced magnetospheric electric field through the short-love (~ 2 hours) prompt penetration of convection electric field, generated by solar wind-magnetosphere dynamo during periods of strong solar wind-magnetosphere interaction. The detailed mechanisms that lead to the generation of prompt penetration electric field (PPEF) during enhanced solar wind-magnetosphere-ionosphere coupling are complex and not fully understood. Evidence of PPEF has been observed under conditions of sudden changes in the interplanetary magnetic field and the solar wind. We study the evolution of field-aligned currents and the response of equatorial electrojet during the March and April 2023 geomagnetic storm. This allows us to understand the processes involving solar wind disturbances interacting with the magnetosphere and coupling into the polar ionosphere, and how the low-latitude ionosphere responded to the enhanced magnetosphere-ionosphere coupling. We observed strong evidence of PPEF during the storms, mainly due to sudden changes of the solar wind dynamic pressure. We will present the observations in the solar wind-magnetosphere- ionosphere system, in particular, field-aligned currents at high latitude ionosphere by Swarm and the equatorial electrojet by Swarm and ground-based magnetometers.