利用IPEI資料研究磁暴效應對電離層磁赤道電場的影響

吳宇鵬(Yu-Peng Wu)

指導教授 ： 黃健民

國立中央大學/地球科學學院/太空科學研究所/碩士(2006年)

摘要

當磁暴發生時，磁赤道電離層電場會與安靜期有明顯的不同。電場發生擾動的機制可分為直接滲透效應以及擾動風發電機效應兩種，前者發生在磁暴一開始的時候，且發生的時間比較短，後者則在磁暴發生後幾個小時才會影響到赤道地區，但持續的時間比較長。除了影響的時間不同外，直接滲透效應會造成磁赤道地區電離層電漿在當地時間白天時會比安靜期多了向上漂移的速度，晚上則呈現向下漂移；擾動風發電機效應在東西方向和鉛直方向皆會造成相當程度的變化。
透過福爾摩沙衛一號飛行時涵蓋整個磁赤道地區的特性，以及其酬載的電離層電漿電動效應儀所搜集的離子漂移速度，我們可以得到磁赤道地區安靜期的電場分佈，進而分析磁暴一開始時的直接滲透效應所產生的電漿漂移的變化，以及隨後擾動風發電機效應在當地所造成的影響。

關鍵字

磁赤道 ； 電離層 ； 磁暴

並列摘要

During storm time, ionospheric electric field in the magnetic equatorial region will have dramatic changes. The mechanism can be categorized into (1) direct penetration (2) disturbance dynamo. The former is triggered at the beginning of the storm and has shorter time duration while the latter starts affecting the equatorial region a few hours later and stays for longer period. Besides the timing, direct penetration will cause a much greater upward drifting speed during the day in equatorial region; at night the drift direction reverses. Disturbance dynamo can cause exchanges of drifts in both zonal and vertical directions.
Taking advantages of the flying path (through the entire magnetic equator) and IPEI payload of FORMOSAT-1, we can gather information of equatorial electric field by ion drift and further analysis the influence to the ionosphere due to the two mechanisms.

並列關鍵字

penetration ； wind dynamo ； storm ； IPEI

參考文獻

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