臺灣博碩士論文加值系統

本論文進行以電離層數值模型進行電離層電漿結構以及電動效應之研究，集中探討電離層電漿洞之成因與大氣潮汐與電離層全電子含量(TEC)之非線性耦合。近期大量研究指出電離層的電漿結構與中氣層至下部熱氣層的大氣潮汐有著密切的關連性，並且在電離層赤道異常帶的下方發現了兩處山洞狀的電漿匱乏帶。本研究以美國海軍研究實驗室(NRL)所開發之三維電離層數值模型SAMI3討論在不同電場以及風場結構之下電離層電漿結構之形貌。所使用的風場包括水平風場經驗模式，以及美國國家大氣中心(NCAR)開發之高層大氣模型TIME-GCM所演算之大氣水平風場。模擬實驗成功的在模型中產生電離層電漿洞的結構，進一步了解到電漿洞的產生與中性風效應產生的輻合與輻散帶分佈有關，並且發現此風場分布的產生與南北風場的TW3分量有著密切的關聯。在潮汐結構方面，則可以獲知中性風效應對TEC的影響大於電場所造成的效應，而中性潮汐對於TEC中的潮汐變化，則會因為非線性交互作用而影響到其他TEC中的潮汐分量。此外，太陽活動會明顯增加電離層F的電動效應以及熱氣層的風場，使得耦合現象的在極大期與極小期有所不同。

This thesis studies the ionospheric plasma structure and electrodynamic using theoretical simulations. This study focus on the mechanism for the formation of ionospheric plasma caves and nonlinear coupling between atmosphere tides and ionospheric total electron content. Variations of the ionospheric electron density structures related to forcing from tides propagating upward from the lower atmosphere have been studied intensively recently. Some observational studies have shown the plasma cave structure exists under the equatorial ionization anomaly. In this study, the electron density structures of plasma caves are reproduced by means of the NRL SAMI3 model, which incorporates neutral winds from the empirical Horizontal Wind Model 2007 (HWM07) and the NCAR Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM). We discuss the relation between different electric/wind fields and ionospheric plasma structure. The simulation results show that the equatorial plasma cave structures are mainly developed by latitudinally convergent neutral winds. The tidal-decomposition analysis further suggests that the convergent neutral wind field and the intensity of the plasma cave are highly associated with the migrating terdiurnal tidal (TW3) component of the meridional neutral wind. In the simulations of the coupling between the atmospheric thermal tides and ionospheric TECs, the influence from neutral wind effects are more significant than from the electric field in ionosphere. We also find nonlinear interaction between atmosphere tides and ionospheric parameters. The level of solar activity also leads different coupling process by the enhanced F region dynamo and photoionization.

摘要 I
Extended Abstract II
誌謝 VII
目錄 VIII
圖目錄 X
第1章 緒論 1
1.1 研究動機 7
1.2 內容概述 8
第2章 地球中性大氣結構與電離層 9
2.1 大氣潮汐 9
2.2 電離層 11
2.2.1 電離層分層結構 11
2.2.2 電離層發電機效應 13
2.2.3 電離層赤道異常帶 13
第3章 模型描述 15
3.1 SAMI model 15
3.1.1 SAMI中的電動效應 16
3.1.2 SAMI中的數值方法 20
3.1.3 電離層電場計算 24
3.1.4 NRLMSISE-00 25
3.1.5 HWM93 26
3.1.6 HWM07 26
3.1.7 Scherliess-Fejer E×B model 28
3.2 TIME-GCM 中高層大氣數值模型 28
第4章 電漿洞模擬結果與討論 31
4.1 SAMI2模擬結果 31
4.1.1 電場擾動強度對電離層形貌的影響 37
4.1.2 電場擾動位置對電離層形貌的影響 41
4.1.3 電場擾動時間長度對電離層形貌的影響 44
4.2 SAMI3模擬結果 48
4.3 潮汐分析 62
4.3.1 潮汐分解方法 62
4.3.1 潮汐分析結果 66
4.4 TIME-GCM模擬結果 71
4.4.1 TIME-GCM電漿洞的年變化 73
第5章 大氣潮汐對電離層的影響 77
5.1 DW1 對電離層的影響 77
5.2 SW2 對電離層的影響 83
5.3 TW3對電離層的影響 93
5.4 太陽活動對潮汐以及電離層的影響 98
第6章 結論 105
參考文獻 108

Anderson, D. N. (1973), A theoretical study of the ionospheric F region equatorial anomaly—I. Theory, Planet. Space Sci., 21, 409–419, doi:10.1016/0032-0633(73)90040-8.
Appleton, E. V. (1946), Two anomalies in the ionosphere, Nature, 157, 691, doi:10.1038/157691a0
Balan, N., and G. J. Bailey (1995), Equatorial plasma fountain and its effects: Possibility of an additional layer, J. Geophys. Res., 100, 21,421–21,432, doi:10.1029/95JA01555.
Chang, L. C., C.-H. Lin, J.-Y. Liu, N. Balan, J. Yue, and J.-T. Lin (2013), Seasonal and local time variation of ionospheric migrating tides in 2007–2011 FORMOSAT-3/COSMIC and TIE-GCM total electron content, J. Geophys. Res. Space Physics, 118, 2545–2564, doi:10.1002/jgra.50268.
Chen, C. H., C. H. Lin, L. C. Chang, J. D. Huba, J. T. Lin, A. Saito, and J. Y. Liu (2013), Thermospheric tidal effects on the ionospheric midlatitude summer nighttime anomaly using SAMI3 and TIEGCM, J. Geophys. Res. Space Physics, 118, doi:10.1002/jgra.50340.
Drob, D. P., et al. (2008), An empirical model of the Earth’s horizontal wind fields: HWM07, J. Geophys. Res., 113, A12304, doi:10.1029/2008JA013668.
Duncan, R. A. (1960), The equatorial F region of the ionosphere, J. Atmos. Terr. Phys., 18, 89–100.
Forbes, J. M., and D. Wu (2006), Solar tides as revealed by measurements of mesosphere temperature by the MLS experiment on UARS, J. Atmos. Sci., 63(7), 1776–1797.
Hanson, W. B., and R. J. Moffett (1966), Ionization transport effects in the equatorial F region, J. Geophys. Res., 71, 5559–5572, doi:10.1029/JZ071i023p05559.
Hedin, A. E., et al. (1996), Empirical wind model for the upper, middle and lower atmosphere, J. Atmos. Terr. Phys., 58, 1421 – 1447, doi:10.1016/0021-9169(95)00122-0.
Huba, J. D., G. Joyce, and J. A. Fedder (2000), Sami2 is Another Model of the Ionosphere (SAMI2): A new low-latitude ionosphere model, J. Geophys. Res., 105, 23,035–23,053, doi:10.1029/2000JA000035.
Huba, J. D., G. Joyce, J. Krall, C. L. Siefring, and P. A. Bernhardt (2010), Self‐consistent modeling of equatorial dawn density depletions with SAMI3, Geophys. Res. Lett., 37, L03104, doi:10.1029/2009GL041492.
Kelly, M. C., 2009: The Earth's Ionosphere, Academic Press, 2nd Edition, Boston
Lee, I. T., J. Y. Liu, C. H. Lin, K.-I. Oyama, C. Y. Chen, and C. H. Chen (2012), Ionospheric plasma caves under the equatorial ionization anomaly, J. Geophys. Res., 117, A11309, doi:10.1029/2012JA017868.
Liu, J. Y., C. Y. Lin, C. H. Lin, H. F. Tsai, S. C. Solomon, Y. Y. Sun, I. T. Lee, W. S. Schreiner, and Y. H. Kuo (2010), Artificial plasma cave in the low‐latitude ionosphere results from the radio occultation inversion of the FORMOSAT‐3/COSMIC, J. Geophys. Res., 115, A07319, doi:10.1029/2009JA015079.
Lu, G., J. D. Huba, and C. Valladares (2013), Modeling ionospheric super-fountain effect based on the coupled TIMEGCM-SAMI3, J. Geophys. Res. Space Physics, 118, 2527–2535, doi:10.1002/jgra.50256
Namba, S., and K.-I. Maeda (1939), Radio Wave Propagation, 86 pp., Corona, Tokyo.
Pancheva, D., Y. Miyoshi, P. Mukhtarov, H. Jin, H. Shinagawa, and H. Fujiwara (2012), Global response of the ionosphere to atmospheric tides forced from below: Comparison between COSMIC measurements and simulations by atmosphere-ionosphere coupled model GAIA, J. Geophys. Res., 117, A07319, doi:10.1029/2011JA017452.
Rishbeth, H. (2000), The equatorial F-layer: Progress and puzzles, Ann. Geophys., 18, 730–739, doi:10.1007/s00585-000-0730-6.
Roble, R. G., and E. C. Ridley (1994), A thermosphere-ionosphere-mesosphere-electrodynamics general circulation model (time-GCM): Equinox solar cycle minimum simulations (30–500 km), Geophys. Res. Lett., 21, 417–420, doi:10.1029/93GL03391.
Roble, R. G. (1995), Energetics of the mesosphere and thermosphere, in The Upper Mesosphere and Lower Thermosphere: A review of Experiment and Theory, AGU Geophys. Monogr. Ser., 87, Washington D.C, pp. 1–21.
Scherliess, L., and B. G. Fejer (1999), Radar and satellite global equatorial F region vertical drift model, J. Geophys, Res., 104, 6829-6842, doi:10.1029/1999JA900025.
Shim, J. S., L. Scherliess, R. W. Schunk, and D. C. Thompson (2010), Neutral wind and plasma drift effects on low and middle latitude total electron content, J. Geophys. Res., 115, A04307, doi:10.1029/2009JA014488.
Wu, D. L., P. B. Hays, and W. R. Skinner (1995), A least squares method for spectral analysis of space-time series, J. Atmos. Sci., 52, 3501–3511.