[P-EM14] [EE] Dynamics in magnetosphere and ionosphere

[PEM14-P15] Global mapping of ionospheric plasma velocity distributions using spherical elementary current systems based on SuperDARN data

*中野 慎也¹、堀 智昭²、関 華奈子²、西谷 望³ (1.情報・システム研究機構　統計数理研究所、2.東京大学大学院理学系研究科、3.名古屋大学宇宙地球環境研究所)

キーワード：ionospheric convection, SuperDARN, spherical elementary current systems

We have developed a method for estimating the global distribution of ionospheric plasma velocity from the SuperDARN data. The SuperDARN observations have a wide spatial coverage. However, it is difficult to obtain a global ionospheric convection map from the SuperDARN data because individual radars give only line-of-sight components of plasma drift velocity and the data are frequently missing. In our technique, the plasma velocity distribution is represented by a sum of divergence-free spherical elementary current systems, which provides a constraint ensuring the divergence free condition. In this paper, we will demonstrate a preliminary results obtained by our newly developed method.