臺灣博碩士論文加值系統

長久以來，科學家主要是以超低頻及特低頻訊號來研究對流層和低層電離層的閃電現象，近年來則有利用特高頻與超高頻波段的氣象雷達做觀測。本論文係利用高頻波段之數位式電離層雷達(Digisonde)於 1996年5月到7月間台灣中壢地區中央大學上空(121°11''E, 24°.58''N)，配合特高頻（VHF)雷達、落雷檢測系統與氣象衛星(GMS)進行閃電對電離層影響之觀測實驗。結果發現閃電會造成電離層F2層臨界頻率(foF2)明顯下降，散塊E層(Es)有相當程度的增強，E層電子濃度下降。

It has been a long time that scientists study lightnings in the troposphere and stratosphere by using very low and extreme low frequency (VLF and ELF). Recently, very high and ultra high frequency (VHP and UHF) are also employed to observe lightnings. In this paper, a Digisonde Portable Sounder (DPS) and a VHF radar, in National Central University (121.11 E, 24.58), lightning detectors in Taiwan, and the metrology satellite, GMS, are used to investigate the lightning events during May to July, 1997. It is found that lightnings result in occurrence of the sporadic E-layer, increase of plasma frequency at the F2-peak, and decrease of plasma frequency at the E-peak.