台灣位處西太平洋電離層之北赤道異常區，此一地區電離層電子濃度之大為世界之最，而變化亦至為複雜。本計畫結合地面電離層雷達鏈、全球定位系統接收機網、泛太平洋地磁觀測鏈，和電離層IRI2001模擬，探討台灣經度電離層赤道異常區之電漿三維結構與變化以及其物理動力機制。分析長期高時間及高空間解析度觀測資料，可獲知隨太陽活動之電離層電子濃度飽和現象、赤道異常峰之形成、和不規則體之生滅。研究太陽擾動及磁暴之電離層電子濃度響應，可探討電離層擾亂、電離層暴和高緯電場直接穿透現象以及中性風和成份的大氣間接效應。結合上述各項研究，可一窺磁暴與太陽風，對電離層赤道異常區電漿結構和運動隨日、季、緯度、以及太陽活動之變化。 The location of Taiwan is right under the ionospheric equatorial ionization anomaly (EIA) region in the West Pacific area. It has been well known that the most pronounced ionospheric electron density is in the EAI region, where the associated structures and dynamics are also very complex. This project combines ground-based measurements of an ionosonde chain, receiver networks of the global positioning system (GPS), and the Circum-Pan pacific Magnetometer Network observing the ionosphere along the Taiwan longitude (120oE). These observations and the International Reference Ionospher (IRI2001) simulations are used to investigate structures and dynamics of ionospheric plasma densities, irregularities, as well as the associated physical mechanisms. The long-term high temporal and spatial resolution databases enable us to examine formations of the equatorial anomaly crest, and appearances of the ionospheric irregularities, under various diurnal, seasonal, latitudinal, and solar activity variations. 研究期間：9608 ~ 9707
