Japan Geoscience Union Meeting 2015

Presentation information

International Session (Oral)

Symbol P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM07] Space Weather, Space Climate, and VarSITI

Tue. May 26, 2015 9:00 AM - 10:45 AM 302 (3F)

Convener:*Ryuho Kataoka(National Institute of Polar Research), Yusuke Ebihara(Research Institute for Sustainable Humanosphere, Kyoto University), Yoshizumi Miyoshi(Solar-Terrestrial Environement Laboratory, Nagoya University), Toshifumi Shimizu(Institute of Space and Astronautical Science, JAXA), Ayumi Asai(Unit for Synergetic Studies of Space, Kyoto University), Hidekatsu Jin(National Institude of Information and Communications Technology), Tatsuhiko Sato(Japan Atomic Energy Agency), Kanya Kusano(Solar-Terrestrial Environment Laboratory, Nagoya University), Hiroko Miyahara(College of Art and Design, Musashino Art University), Takuji Nakamura(National Institute of Polar Research), Kazuo Shiokawa(Solar-Terrestrial Environment Laboratory, Nagoya University), Kiminori Itoh(Graduate School of Engineering, Yokohama National University), Chair:Kazuo Shiokawa(Solar-Terrestrial Environment Laboratory, Nagoya University)

10:00 AM - 10:15 AM

[PEM07-36] Responses of polar cap ionosphere to successive CMEs in Dec 2014: 5 days continuous monitoring with two all-sky imagers

*Keisuke HOSOKAWA1, Satoshi TAGUCHI2, Kazuo SHIOKAWA3, Yasunobu OGAWA4, Yuichi OTSUKA3 (1.University of Electro-Communications, 2.Graduate School of Science, Kyoto University, 3.Solar-Terrestrial Environment Laboratory, Nagoya University, 4.National Institute of Polar Research)

Keywords:Polar cap, Polar cap patches, Polar cap aurora, Coronal Mass Ejection (CME)

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