日本地球惑星科学連合2018年大会

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[EE] 口頭発表

セッション記号 M (領域外・複数領域) » M-GI 地球科学一般・情報地球科学

[M-GI22] Data assimilation: A fundamental approach in geosciences

2018年5月20日(日) 09:00 〜 10:30 302 (幕張メッセ国際会議場 3F)

コンビーナ:中野 慎也(情報・システム研究機構 統計数理研究所)、藤井 陽介(気象庁気象研究所)、宮崎 真一(京都大学理学研究科、共同)、三好 建正(理化学研究所計算科学研究機構)、座長:藤井 陽介

09:00 〜 09:15

[MGI22-01] Assimilation of EUV and ENA measurements for modeling of the inner magnetosphere

*中野 慎也1Brandt Pontus2Fok Mei-Ching3 (1.情報・システム研究機構 統計数理研究所、2.The Johns Hopkins University Applied Physics Laboratory、3.NASA Goddard Space Flight Center)

キーワード:データ同化、リングカレント、プラズマ圏、アンサンブルカルマンフィルタ、内部磁気圏

The observations in the magnetosphere are usually sparse in space. It is thus basically difficult to obtain a global picture of the magnetosphere. However, remote imaging observation from the IMAGE satellite provided the information on the global structures of the plasmasphere and the ring current, both of which play important roles in various physical processes in the inner magnetosphere. The extreme ultraviolet (EUV) measurement from IMAGE provided the information on the global structure of the plasmasphere where cold plasma is densely concentrated. The measurement of energetic neutral atoms (ENA) provided the information on the global structure and energy spectrum of the ring current which consists of high energy ions of tens of keV. In our previous studies, we conducted the EUV data assimilation and the ENA data assimilation for the modeling of the plasmasphere and the ring current, respectively. We are developing a data assimilation framework for reproducing temporal evolution of the plasmasphere and the ring current by exploiting the EUV and ENA imaging data from the IMAGE satellite. The result of some preliminary experiments showed the spatial distributions of the plasmasphere and the ring current can be estimated by assimilating the EUV and ENA data into an inner magnetosphere model. The electric potential distribution which controls the distributions of the plasmasphere and the ring current was successfully obtained. It was also demonstrated that the ENA and EUV data would provide the complementary information on the inner magnetosphere because the plasmasphere and the ring current are located in different regions.