1999-2004 年華衛一號（福衛一號）的資料顯示，日落後所產生的赤道區電離層密度不規體在當地時間的分佈圖會有季節上的差異。春、秋及冬季的高峰期落在21-22 時上，而夏季的高峰期則晚一個小時，落在22-23 時上。依據最近的研究結果，赤道區電離層密度不規體只與電離層電動力變化有關，與大氣因素如重力波的激動並沒有太大的關連。本論文將對日落後，經向電漿流返轉的時間與密度不規體的產生，尋找其關係，並提出經向電漿流返轉時間隨季節變化的原因及結果。 ; Data from ROCSAT-1 indicates that the peaks of local-time (LT) distribution of equatorial density irregularities have seasonal variations. The peak appears at 21-22 LT during March and September equinoxes, and December solstice, but lags one hour to 22-23 LT in June solstices. As the cause of density irregularity occurrences has been linked to the electrodynamics of the post-sunset ionospheric conditions without any role from the gravity seeding perturbations of atmospheric disturbances, we will present a causal relationship between the local time reversal of the post-sunset zonal flow and the peak of irregularity occurrences. ; 研究期間 9708 ~ 9807
