10:00 〜 10:15
[PEM07-36] 2014 年 12 月の連発 CME に対する極冠域電離圏の応答: 2 台の全天イメージャによる 5 日間連続モニタリング
キーワード：極冠域, 極冠パッチ, 極冠オーロラ, コロナ質量放出
In December 2014, three coronal mass ejections (CMEs) occurred successively during 4 days
interval from December 18 to 21. These CMEs arrived at the Earth respectively at December 21, 22
and 23 and caused a small magnetic storm (Dst ~-50 nT). During this interval, two all-sky airglow
imagers were operative in Longyearbyen, Norway (78.1N, 15.5E) and Resolute Bay, Canada (74.7N, 265.1E)
and monitoring the polar cap ionosphere continuously for 5 days from December 20 to 24. The two
all-sky imagers observed continuous generation/propagation of polar cap patches from the dayside
towards the nightside across the polar cap region during a prolonged interval of southward IMF Bz.
Such a continuous transportation of high-density plasma is visualized for the first time. At the
time of the arrival of second CME, the IMF Bz was directed strongly northward. During this period,
the polar cap shrank significantly, which implies that the magnetosphere was almost closed during
such a strongly northward IMF condition. By using the 5 days continuous optical data in the polar
cap region, we will discuss various responses of polar cap ionosphere to CME-induced solar wind
disturbances.
interval from December 18 to 21. These CMEs arrived at the Earth respectively at December 21, 22
and 23 and caused a small magnetic storm (Dst ~-50 nT). During this interval, two all-sky airglow
imagers were operative in Longyearbyen, Norway (78.1N, 15.5E) and Resolute Bay, Canada (74.7N, 265.1E)
and monitoring the polar cap ionosphere continuously for 5 days from December 20 to 24. The two
all-sky imagers observed continuous generation/propagation of polar cap patches from the dayside
towards the nightside across the polar cap region during a prolonged interval of southward IMF Bz.
Such a continuous transportation of high-density plasma is visualized for the first time. At the
time of the arrival of second CME, the IMF Bz was directed strongly northward. During this period,
the polar cap shrank significantly, which implies that the magnetosphere was almost closed during
such a strongly northward IMF condition. By using the 5 days continuous optical data in the polar
cap region, we will discuss various responses of polar cap ionosphere to CME-induced solar wind
disturbances.