福衛三號低層大氣溫度資料分析

An analysis of FORMOSAT-3/COSMIC-retrieved temperature data in the atmosphere

劉智中(Chih-Chung Liu)

指導教授 ： 朱延祥

國立中央大學/地球科學學院/太空科學研究所/碩士(2008年)

摘要

福爾摩沙衛星三號(COSMIC)利用電波掩星法反演出電離層電子濃度以及低層大氣溫度、氣壓、水汽壓等大氣參數。由於觀測範圍涵蓋全球且每日所得到資料量夠多等特性，因此福衛三號掩星觀測資料適合進行全球赤道地區電離層以及低層大氣波傳播特性分析。本文主要利用福衛三號2006年9月到2008年2月掩星觀測資料，分析赤道地區低層大氣溫度及電離層電子濃度變化。透過特殊的資料處理及篩選，分析出赤道地區對流層頂及平流層底附近存在赤道Kelvin波。波數1的赤道Kelvin波，波長為360經度，週期約為15天左右，相速約為2578km/day;而波數2的赤道Kelvin波，波長為180經度，週期約為10天左右，相速約為2088km/day。另外在低層大氣以及電離層資料的整合性研究中，發現在秋季時低層大氣及電離層皆明顯存在wavenumber-4的結構，推測此現象是由低層大氣固定性潮汐所造成;在其餘的季節wavenumber-4的結構依舊可發現存在於低層大氣中，但在電離層中則改以其它形式出現(wavenumber-2 or 3)。

關鍵字

凱文波 ； 電離層 ； 福衛三號溫度資料

並列摘要

In this paper, we analyze the variation of ionosphere electron density profiles and atmosphere temperature profiles. On the basis of 18 month data (September 2006 - February 2008), we find that the zonal wave number 1 Kelvin wave that is characterized by zonal wave length of 360°and wave periods of 15 days, posses horizontal phase velocity of 2578 km/day; and the zonal wave number 2 Kelvin wave with zonal wave length 180° and wave periodic of 10 days has phase velocity of 2088 km/day. In the study of lower and upper atmospheric coupling, we find that wavenumber-4 structure exists in autumn, and it’s very likely that lower atmosphere non-migrating tide in lower atmosphere affects ionospheric E and F regions. The wavenumber-4 structure in other seasons also occurs in the lower atmosphere, but changes to other type (wavenumber-2 or 3) in the upper ionosphere.

並列關鍵字

FORMOSAT-3 ； COSMIC ； Kelvin wave ； wave number 4

參考文獻

2.C. H. Lin, W.Wang, M.E. Hagan, C. C. Hsiao, T. J. Immel, M. L. Hsu, J. Y. Liu, L. J. Paxton, T. W. Fang, and C. H. Liu, Plausible effect of atmospheric tides on the equatorial ionosphere observed by the FORMOSAT-3/COSMIC: Three-dimensional electron density structures, Geophys. Res. Lett., Vol. 34,2007.

3.C. H. Lin, C.C. Hsiao, J. Y. Liu, and C. H. Liu, Longitudinal structure of the equatorial ionosphere: Time evolution of the four-peaked EIA structure, J. Geophys. Res., Vol. 112, 2007.

4.Fjeldbo, G., A. J. Kliore, and V. L. Eshleman, The netural atmosphere of Venus as studies with the Mariner V radio occultation experiment, Astron. J., 76,123-140,1971.

5.H. F. Tsai, Toshitaka TSUDA, George A. Hajj, Jens Wickert, Yuichi Aoyama, Equatorial Kelvin Waves Observed with GPS Occultation Measurements(CHAMP and SAC-C), Journal of the Meteorological Society of Japan, 2004.

6.Kenneth Davis, Ionospheric Radio, Peter Peregrinus Ltd, London, 1990.