本文研究並統計低緯度電離層赤道異常區之中尺度電離層移行擾動(Medium–Scale Traveling Ionospheric Disturbances, MSTIDs)，以及赤道電漿泡(Equatorial Plasma Bubbles, EPBs)。吾人利用中央氣象局餘100個GPS接收站的電離層全電子含量(Total electron content, TEC)資料進行分析，為了要區別以及分類MSTIDs和EPBs，吾人應用三維快速傅立葉轉換和支援向量機演算法來進行自動判別。判別後之統計結果與福爾摩沙衛星三號(Constellation Observing System for Meteorology, Ionosphere, and Climate, COSMIC)演星資料以及高解析度全球大氣耦合模式(Whole Atmosphere Community Climate Model, WACCM)比較討論其季節性特徵以及發生機制，可以得到以下結論:第一，往南向傳的MSTIDs於冬季以及春季時，幾乎於所有的白天到午夜都可以觀測到，且其主要以正南向以及東南向為主；相較而言，於夏季，南向的MSTIDs，在夜晚九點到半夜五點好發，其主要從日本地區傳遞過來且以西南向為主。第二，北向傳的MSTIDs，較多於春季以及夏季的中午至半夜被觀測到，且在春季有著第二波的發生高峰，其可能的發生機制為大氣重力波。第三，赤道電漿泡於四季的發生機率依序為，春季大於秋季，再來是夏季，最後是冬季。

This study investigates the medium–scale traveling ionospheric disturbances (MSTIDs) statistically at the low–latitude equatorial ionization anomaly (EIA) region in the northern hemisphere. I apply both three–dimensional fast Fourier transform (3D–FFT) and support vector machine (SVM) to identify MSTID from other waves or irregularity features, such as equatorial plasma bubble (EPB) from TEC observations by a network of ground-based GNSS receivers around Taiwan. Statistical results together with additional observations from radio occultation of FORMOSAT-3/COSMIC data and neutral atmosphere perturbations from the high–resolution Whole Atmosphere Community Climate Model (WACCM) indicate the following characteristics. First, the southward (equatorward) MSTIDs are observed almost every day from 08:00 to 21:00 LT during Spring and Winter. At midnight, southward MSTIDs are more discernible in Summer and they are majorly propagating from Japan at mid-latitude region. Second, northward (poleward) MSTIDs are more frequently detected among 12:00 to 21:00 LT in Spring and Summer with secondary occurrence peak during day of year 100 to 140, which is likely connected to the atmospheric gravity waves (AGWs).

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