日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

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-EM11] Dynamics of Magnetosphere and Ionosphere

2019年5月29日(水) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:中溝 葵(情報通信研究機構 電磁波研究所)、尾崎 光紀(金沢大学理工研究域電子情報学系)、藤本 晶子(九州工業大学)、堀 智昭(名古屋大学宇宙地球環境研究所)

[PEM11-P22] Ionospheric F-region Drift Measurements Derived from DPS-4D at Zhongshan Station, Antarctic

*Xiangcai Chen1 (1.Polar Research Institute of China)

キーワード:Digisonde DPS 4, Doppler frequency shift, remote sensing, polar ionosphere, plasma drift

By means of high-frequency radio sounding, the ionospheric plasma drift can be measured by the Doppler frequency shift of signal. In this paper we analyze the ionospheric F-region plasma motion performed by Digisonde Portable Sounder (DPS-4D) at cusp latitude over Zhongshan Station in Antarctic. By restricting the echo arrival angle, and selecting the reflection height range at 175 – 475 km, we present the variation of the F-region plasma drift measurements by setting limits on the Doppler frequency shift. Base on the 7.5 min interval Digisonde drift data from November 2011 to February 2012, we considered the variations of the plasma drift in F-region under the different geomagnetic activity (Kp) and magnetic local time, as well as it correlation with interplanetary magnetic field (IMF). The results indicate that properly restricting the Doppler frequency shift of the echo has a strong effect that contributes to the accurate and robust measurements of the ionospheric plasma drift. The mean value of horizontal drift mostly leveled off to about 600 m/s at altitude around of 230 km, while the field-aligned component of drift showed mean values of -25 m/s near pre-noon and +40 m/s during the night. These strong diurnal variations have dependence on the sign and strength of the IMF By and Bz components. It implies that the contraction and expansion of the polar cap with Kp and the convection in the proximity of the throat with different IMF conditions have a profound influence on the observed drift velocities.