[P-EM36_28PO1] 大気圏・電離圏

[PEM36-P17] パラツンカ上空における630nm大気光イメージャとHFレーダーを用いたMSTIDの統計解析

*箕浦 武¹、鈴木 臣¹、塩川 和夫¹、大塚 雄一¹、西谷 望¹、細川 敬祐² (1.名古屋大学太陽地球環境研究所、2.電気通信大学大学院情報理工学研究科)

キーワード：大気光イメージャー, 北海道SuperDARNレーダー, 中規模伝搬性電離圏擾乱

Medium-scale traveling ionospheric disturbances (MSTIDs), which typically have a horizontal scale of 100-500 km and a period of ~1 h, are frequently observed in the F region ionosphere at middle latitudes. To date, quite a few observations of MSTIDs have been carried out especially in the middle latitudes; they predominantly had a northwest-southeast, (northeast-southwest) frontal structure and propagated southwestward (northeastward) in the northern (southern) hemisphere, however their generation and propagation mechanisms are not clear yet. Suzuki et al. [2009] investigated two dimensional characteristics of a nighttime MSTID using the SuperDARN Hokkaido HF radar at Rikubetsu, (43.5 N, 143.6 E), Japan, and an OI 630-nm airglow imager located at Paratunka (53.0 N, 158.2 E), Russia, within the radar field of view (FOV). The Doppler velocities of MSTID echoes observed by the SuperDARN radar showed systematic polarity changes which were consistent with airglow intensity variations. The electric field estimated from the airglow and SuperDARN observations, however, seems to be improbable and the E-F coupling processes would be important to explain the inconsistency. We investigated statistical characteristics of nighttime MSTIDs. Based on the coordinated airglow and SuperDARN measurements from 2011 to 2013, we investigated the relation between the MSTID amplitudes in the 630-nm airglow intensity and the Doppler velocities of the FAI echoes associated with the MSTID pattern. This study may give an observational insight into the E-F coupling quantitatively.
In this presentation, we will report the statistics of the relation of the FAI echoes and airglow signatures of the observed MSTIDs (5 events), which showed spatially conjugation in the radar FOV.