請用此 Handle URI 來引用此文件：
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/62983完整後設資料紀錄
| DC 欄位 | 值 | 語言 |
|---|---|---|
| dc.contributor.advisor | 趙丰(Benjamin Fong Chao),陳于高(Yue-Gau Chen) | |
| dc.contributor.author | Chi-Hua Chung | en |
| dc.contributor.author | 鍾綺樺 | zh_TW |
| dc.date.accessioned | 2021-06-16T16:17:30Z | - |
| dc.date.available | 2023-06-09 | |
| dc.date.copyright | 2020-06-09 | |
| dc.date.issued | 2020 | |
| dc.date.submitted | 2020-05-24 | |
| dc.identifier.citation | Alboussière, T. (2008). Course 1 Fundamentals of MHD. Dynamos: Lecture Notes of the Les Houches Summer School 2007 (Vol. 88, pp. 1-44). Amsterdam, Netherlands: Elsevier. Amit, H. (2014). Can downwelling at the top of the Earth’s core be detected in the geomagnetic secular variation? Physics of the Earth and Planetary Interiors, 229, 110-121. https://doi.org/10.1016/j.pepi.2014.01.012 Amit, H., Olson, P. L. (2004). Helical core flow from geomagnetic secular variation. Physics of the Earth and Planetary Interiors, 147(1), 1-25. https://doi.org/ 10.1016/j.pepi.2004.02.006 Amit, H., Pais, M. A. (2013). Differences between tangential geostrophy and columnar flow. Geophysical Journal International, 194(1), 145-157. https://doi.org/10.1093/gji/ggt077 Aubert, J. (2012). Flow throughout the Earth's core inverted from geomagnetic observations and numerical dynamo models. Geophysical Journal International, 192(2), 537-556. https://doi.org/10.1093/gji/ggs051 Aubert, J., Amit, H., Hulot, G., Olson, P. L. (2008). Thermochemical flows couple the Earth's inner core growth to mantle heterogeneity. Nature, 454(7205), 758-761. https://doi.org/10.1038/nature07109 Aubert, J., Finlay, C. C., Fournier, A. (2013). Bottom-up control of geomagnetic secular variation by the Earth's inner core. Nature, 502(7470), 219-223. https://doi.org/10.1038/nature12574 Aurnou, J., Andreadis, S., Zhu, L., Olson, P. (2003). Experiments on convection in Earth’s core tangent cylinder. Earth and Planetary Science Letters, 212(1-2), 119-134. https://doi.org/10.1016/S0012-821X(03)00237-1 Aurnou, J. M., Brito, D., Olson, P. L. (1996). Mechanics of inner core super-rotation. Geophysical Research Letters, 23(23), 3401-3404. https://doi.org/10.1029/96gl03258 Backus, G., Parker, R. Constable, C. (1996). Foundations of geomagnetism. New York, NY: Cambridge University Press. Backus, G., Mouël, J. L. L. (1986). The region on the core—mantle boundary where a geostrophic velocity field can be determined from frozen-flux magnetic data. Geophysical Journal International, 85(3), 617-628. Bardsley, O. P. (2018). Could hydrodynamic Rossby waves explain the westward drift? Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 474(2213). https://doi.org/10.1098/rspa.2018.0119 Bloxham, J. (1986). The expulsion of magnetic flux from the Earth's core. Geophysical Journal International, 87(2), 669-678. https://doi.org/10.1111/j.1365-246X.1986tb06643.x Bloxham, J., Gubbins, D. (1987). Thermal core–mantle interactions. Nature, 325(6104), 511. Braginsky, S. I., (1993). MAC-oscillations of the hidden ocean of the core. Journal of geomagnetism and geoelectricity, 45(11-12), 1517-1538. https://doi.org/10.5636/jgg.45.1517 Buffett, B. A. (1996). Gravitational oscillations in the length of day. Geophysical Research Letters, 23(17), 2279-2282. https://doi.org/10.1029/96gl02083 Buffett, B. A. (1997). Geodynamic estimates of the viscosity of the Earth's inner core. Nature, 388(6642), 571. https://doi.org/10.1038/41534 Buffett, B. A. (2010). Chemical stratification at the top of Earth's core: Constraints from observations of nutations. Earth and Planetary Science Letters, 296(3-4), 367-372. https://doi.org/10.1016/j.epsl.2010.05.020 Buffett, B. A. (2014). Geomagnetic fluctuations reveal stable stratification at the top of the Earth’s core. Nature, 507(7493), 484. https://doi.org/10.1038/nature13122 Buffett, B. A. (2015). Core–Mantle Interactions. Treatise on Geophysics (Vol. 8, pp. 213-214). Amsterdam, Netherlands: Elsevier. Buffett, B. A., Knezek, N., Holme, R. (2016). Evidence for MAC waves at the top of Earth's core and implications for variations in length of day. Geophysical Journal International, 204(3), 1789-1800. https://doi.org/10.1093/gji/ggv552 Buffett, B. A., Seagle, C. T. (2010). Stratification of the top of the core due to chemical interactions with the mantle. Journal of Geophysical Research: Solid Earth, 115(B4). https://doi.org/10.1029/2009JB006751 Bullard, E. C., Freedman, C., Gellman, H., Nixon, J. (1950). The westward drift of the Earth's magnetic field. Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 243(859), 67-92. https://doi.org/10.1098/rsta.1950.0014 Busse, F. H. (1970). Thermal instabilities in rapidly rotating systems. Journal of Fluid Mechanics, 44(3), 441-460. https://doi.org/10.1017/S0022112070001921 Busse, F. H. (1975). A model of the geodynamo. Geophysical Journal International, 42(2), 437-459. https://doi.org/10.1111/j.1365-246X.1975.tb05871.x Busse, F. H. (1976). Generation of planetary magnetism by convection. Physics of the Earth and Planetary Interiors, 12(4), 350-358. https://doi.org/10.1016/0031-9201(76)90030-3 Busse, F. H. (2002). Convective flows in rapidly rotating spheres and their dynamo action. Physics of fluids, 14(4), 1301-1314. https://doi.org/10.1063/1.1455626 Cao, H., Yadav, R. K., Aurnou, J. M. (2018). Geomagnetic polar minima do not arise from steady meridional circulation. Proceedings of the National Academy of Sciences, 115(44), 11186-11191. https://doi.org/10.1073/pnas.1717454115 Chandrasekhar, S. (1961). Hydrodynamic and hydromagnetic stability. Oxford, United Kingdom: Oxford University Press. Chao, B. F. (2005). On inversion for mass distribution from global (time-variable) gravity field. Journal of Geodynamics, 39(3), 223-230. https://doi.org/10.1016/j.jog.2004.11.001 Chao, B. F. (2017a). Dynamics of axial torsional libration under the mantle‐inner core gravitational interaction. Journal of Geophysical Research: Solid Earth, 122(1), 560-571. https://doi.org/10.1002/2016JB013515 Chao, B. F. (2017b). Dynamics of the inner core wobble under mantle‐inner core gravitational interactions. Journal of Geophysical Research: Solid Earth, 122(9), 7437-7448. https://doi.org/10.1002/2017JB014405 Chao, B. F., Chung, W., Shih, Z., Hsieh, Y. (2014). Earth's rotation variations: a wavelet analysis. Terra Nova, 26(4), 260-264. https://doi.org/10.1111/ter.12094 Civet, F., Thébault, E., Verhoeven, O., Langlais, B., Saturnino, D. (2015). Electrical conductivity of the Earth's mantle from the first Swarm magnetic field measurements. Geophysical Research Letters, 42(9), 3338-3346. https://doi.org/10.1002/2015gl063397 Davidson, P. A. (2015). Turbulence: an introduction for scientists and engineers. Oxford, United Kingdom: Oxford University Press. Davidson, P. A. (2016). Introduction to Magnetohydrodynamics (2nd ed.). New York, NY: Cambridge University Press. Ding, H., Chao, B. F. (2018). A 6-year westward rotary motion in the Earth: Detection and possible MICG coupling mechanism. Earth and Planetary Science Letters, 495, 50-55. https://doi.org/10.1016/j.epsl.2018.05.009 Dumberry, M. (2008). Course 7 Taylor's constraint and torsional oscillations. Lecture Notes of the Les Houches Summer School 2007 (Vol. 88, pp. 383-401). Amsterdam, Netherlands: Elsevier. Finlay, C. C. (2005). Hydromagnetic waves in Earth's core and their influence on geomagnetic secular variation (Doctoral dissertation). Retrieved from The National Space Institute at the Technical University of Denmark (https://ftp.spacecenter.dk/pub/cfinl/publications/). Leeds, United Kingdom: University of Leeds. Finlay, C. C. (2008). Course 8 Waves in the presence of magnetic fields, rotation and convection. Dynamos: Lecture Notes of the Les Houches Summer School 2007 (Vol. 88, pp. 403-450). Amsterdam, Netherlands: Elsevier. Finlay, C. C., Aubert, J., Gillet, N. (2016). Gyre-driven decay of the Earth’s magnetic dipole. Nature communications, 7, 10422. https://doi.org/10.1038/ncomms10422 Finlay, C. C., Dumberry, M., Chulliat, A., Pais, M. A. (2010). Short Timescale Core Dynamics: Theory and Observations. Space Science Reviews, 155(1-4), 177-218. https://doi.org/10.1007/s11214-010-9691-6 Finlay, C. C., Jackson, A. (2003). Equatorially dominated magnetic field change at the surface of Earth's core. Science, 300(5628), 2084-2086. https://doi.org/10.1126/science.1083324 Gauss, C. F. (1833). Intensitas vis magneticae terrestris ad mensuram absolutam revocata. Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London 3, 166–174. Gauss, C. F. (1839). Allgemeine Theorie des Erdmagnetismus, Resultate aus den Beobachtungen des Magnetischen Vereins im Jahre 1838. Scientific Memoirs Selected from the Transactions of Foreign Academies and Learned Societies and from Foreign Journals, 184-251. Gillet, N., Jault, D., Canet, E., Fournier, A. (2010). Fast torsional waves and strong magnetic field within the Earth's core. Nature, 465(7294), 74-77. https://doi.org/10.1038/nature09010 Gillet, N., Jault, D., Finlay, C. (2015). Planetary gyre, time‐dependent eddies, torsional waves, and equatorial jets at the Earth's core surface. Journal of Geophysical Research: Solid Earth, 120(6), 3991-4013. https://doi.org/10.1002/2014JB011786 Gillet, N., Pais, M., Jault, D. (2009). Ensemble inversion of time‐dependent core flow models. Geochemistry, Geophysics, Geosystems, 10(6). https://doi.org/10.1029/2008GC002290 Glane, S., Buffett, B. A. (2018). Enhanced Core-Mantle Coupling Due to Stratification at the Top of the Core. Frontiers in Earth Science, 6. https://doi.org/10.3389/feart.2018.00171 Glatzmaier, G. A., Olson, P. L. (2005). Probing the geodynamo. Scientific American, 292(4), 50-57. Gray, C. (1979). Magnetic multipole expansions using the scalar potential, American Journal of Physics, 47(5), 457-459. https://doi.org/ 10.1119/1.11816 Griffiths, D. J. (2013). Introduction to electrodynamics (4th ed.). Boston, MA: Pearson. Gubbins, D., Bloxham, J. (1987). Morphology of the geomagnetic field and implications for the geodynamo. Nature, 325(6104), 509. Gubbins, D., Davies, C. J. (2013). The stratified layer at the core–mantle boundary caused by barodiffusion of oxygen, sulphur and silicon. Physics of the Earth and Planetary Interiors, 215, 21-28. https://doi.org/10.1016/j.pepi.2012.11.001 Halley, E. (1692). An account of the cause of the change of the variation of the magnetical needle. with an hypothesis of the structure of the internal parts of the earth: as it was proposed to the Royal Society in one of their late meetings. Philosophical Transactions of the Royal Society of London, 17(195), 563-578. Hannachi, A., Jolliffe, I. T., Stephenson, D. B. (2007). Empirical orthogonal functions and related techniques in atmospheric science: A review. International Journal of Climatology: A Journal of the Royal Meteorological Society, 27(9), 1119-1152. https://doi.org/10.1002/joc.1499 Hide, R. (1966). Free hydromagnetic oscillations of the Earth's core and the theory of the geomagnetic secular variation. Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 259(1107), 615-647. https://doi.org/10.1098/rsta.1966.0026 Holme, R. (2015). Large-scale flow in the core. Treatise on geophysics (Vol. 8, pp. 91-113). Amsterdam, Netherlands: Elsevier. Hori, K., Jones, C. A., Teed, R. J. (2015). Slow magnetic Rossby waves in the Earth's core. Geophysical Research Letters, 42(16), 6622-6629. https://doi.org/10.1002/2015gl064733 Jackson, A. (1997). Time-dependency of tangentially geostrophic core surface motions. Physics of the earth and planetary interiors, 103(3-4), 293-311. https://doi.org/10.1016/S0031-9201(97)00039-3 Jackson, A., Finlay, C. C. (2015). Geomagnetic secular variation and its applications to the core. Treatise on Geophysics (Vol. 5, pp. 137-184). Amsterdam, Netherlands: Elsevier. Jackson, A., Jonkers, A. R., Walker, M. R. (2000). Four centuries of geomagnetic secular variation from historical records. Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 358(1768), 957-990. https://doi.org/10.1098/rsta.2000.0569 Jault, D., Gire, C., Le Mouël, J. (1988). Westward drift, core motions and exchanges of angular momentum between core and mantle. Nature, 333(6171), 353. Jault, D., Finlay, C. C. (2015). Waves in the Core and Mechanical Core–Mantle Interactions. Treatise on geophysics (Vol. 8, pp. 255-244). Amsterdam, Netherlands: Elsevier. Jaupart, E., Buffett, B. (2017). Generation of MAC waves by convection in Earth's core. Geophysical Journal International, 209(2), 1326-1336. https://doi.org/10.1093/gji/ggx088 Jones, C. A. (2015). Thermal and Compositional Convection in the Outer Core. Treatise on geophysics (Vol. 8, pp. 131-185). Amsterdam, Netherlands: Elsevier. Lowes, F., Duka, B. (2011). Magnetic multipole moments (Gauss coefficients) and vector potential given by an arbitrary current distribution. Earth, planets and space, 63(12), 1-6. https://doi.org/ 10.5047/eps.2011.08.005 Meyer-Vernet, N. (2007). Basics of the solar wind. New York, NY: Cambridge University Press. Monnereau, M., Calvet, M., Margerin, L., Souriau, A. (2010). Lopsided growth of Earth's inner core. Science, 328(5981), 1014-1017. https://doi.org/10.1126/science.1186212 Nimmo, F. (2015). Energetics of the Core. Treatise on geophysics (Vol. 8, pp. 27-55). Amsterdam, Netherlands: Elsevier. Niu, F., Wen, L. (2001). Hemispherical variations in seismic velocity at the top of the Earth's inner core. Nature, 410(6832), 1081-1084. https://doi.org/10.1038/35074073 Olson, P. L. (2007). Thermal Wind. Encyclopedia of Geomagnetism and Paleomagnetism (pp. 945-947). New York, NY: Springer. Olson, P. L. (2015). Core dynamics: an introduction and overview. Treatise on Geophysics (Vol. 8, pp. 1-25). Amsterdam, Netherlands: Elsevier. Olson, P. L., Aurnou, J. M. (1999). A polar vortex in the Earth's core. Nature, 402(6758), 170. https://doi.org/10.1038/46017 Olsen, N., Mandea, M., Sabaka, T.J., Tøffner-Clausen, L. (2010). The CHAOS-3 geomagnetic field model and candidates for the 11th generation IGRF, Earth Planets Space, 62, 719–727. https://doi.org/10.5047/eps.2010.07.003 Pais, M. A., Jault, D. (2008). Quasi-geostrophic flows responsible for the secular variation of the Earth's magnetic field. Geophysical Journal International, 173(2), 421-443. https://doi.org/10.1111/j.1365-246X.2008.03741.x Parkinson, W. D. (1983). Introduction to geomagnetism. Edinburgh, United Kingdom: Scottish Academic Press. Peddie, N. W. (1982). International Geomagnetic Reference Field: the third generation. Journal of geomagnetism and geoelectricity, 34(6), 309-326. https://doi.org/10.5636/jgg.34.309 Preisendorfer, R. W., Mobley, C. D. (1988). Principal Component Analysis in Meteorology and Oceanography. Amsterdam, New York: Elsevier. Proudman, J. (1916). On the motion of solids in a liquid possessing vorticity. Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 92(642), 408-424. https://doi.org/10.1098/rspa.1916.0026 Roberts, P. H., Aurnou, J. M. (2012). On the theory of core-mantle coupling. Geophysical Astrophysical Fluid Dynamics, 106(2), 157-230. https://doi.org/10.1080/03091929.2011.589028 Roberts, P. H. (2015). Theory of the geodynamo. Treatise on geophysics (Vol. 8, pp. 67-105). Amsterdam, Netherlands: Elsevier. Rochester, M. G., Crossley, D, J., Chao, B. F. (2018). On the physics of the inner core wobble: corrections to 'Dynamics of the inner-core wobble under mantle-inner core gravitational interactions' by B. F. Chao. Journal of Geophysical Research: Solid Earth, 123(11), 9998-10. https://doi.org/10.1029/2018JB016506 Rossby, C. G. (1939). Relation between variations in the intensity of the zonal circulation of the atmosphere and the displacements of the semi-permanent centers of action. Journal of Marine Research, 2, 38-55. Shlens, J. (2014). A tutorial on principal component analysis. arXiv preprint arXiv: 1404.1100. Song, X., Richards, P. G. (1996). Seismological evidence for differential rotation of the Earth's inner core. Nature, 382(6588), 221. https://doi.org/10.1038/382221a0 Stacey, F. D., Davis, P. M. (2008). Physics of the Earth. New York, NY: Cambridge University Press. Taylor, G. I. (1917). Motion of solids in fluids when the flow is not irrotational. Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 93(648), 99-113. https://doi.org/10.1098/rspa.1917.0007 Teed, R. J., Jones, C. A., Tobias, S. M. (2014). The dynamics and excitation of torsional waves in geodynamo simulations. Geophysical Journal International, 196(2), 724-735. https://doi.org/10.1093/gji/ggt432 Teed, R. J., Jones, C. A., Tobias, S. M. (2019). Torsional waves driven by convection and jets in Earth’s liquid core. Geophysical Journal International, 216(1), 123-129. https://doi.org/10.1093/gji/ggy416 Thébault, E., Finlay, C. C., Beggan, C. D., Alken, P., Aubert, J., Barrois, O., Bertrand, F., Bondar, T., Boness, A., Brocco, L., Canet, E., Chambodut, A., Chulliat, A., Coïsson, P., Civet, F., Du, A., Fournier, A., Fratter, I., Gillet, N., Hamilton, B., Hamoudi, M., Hulot, G., Jager, T., Korte, M., Kuang, W., Lalanne, X., Langlais, B., Léger, J. M., Lesur, V., Lowes, F. J., Macmillan, S., Mandea, M., Manoj, C., Maus, S., Olsen, N., Petrov, V., Ridley, V., Rother, M., Sabaka, T .J., Saturnino, D., Schachtschneider, R., Sirol, O., Tangborn, A., Thomson, A., Tøffner-Clausen, L., Vigneron, P., Wardinski, I., Zvereva, T. (2015). International Geomagnetic Reference Field: the 12th generation. Earth, Planets and Space, 67(1). https://doi.org/10.1186/s40623-015-0228-9 Tilgner, A. (2015). Rotational Dynamics of the Core. Treatise on geophysics, (Vol. 8, pp. 183-212). Amsterdam, Netherlands: Elsevier. Xu, W. Y., Sun, W. (1998). Eigen mode analysis of Earth’s main magnetic field. Chinese Journal of Geophysics, 41(1), 1-9. Xu, W. Y. (2002). Revision of the high-degree Gauss coefficients in the IGRF 1945-1955 models by using natural orthogonal component analysis. Earth, Planets and Space, 54(7), 753-761. https://doi.org/10.1186/BF03351728 Yu, Y., Chao, B. F., García‐García, D., Luo, Z. (2018). Variations of the Argentine Gyre observed in the GRACE time‐variable gravity and ocean altimetry measurements. Journal of Geophysical Research: Oceans, 123(8), 5375-5387. https://doi.org/10.1029/2018JC014189 Yukutake, T. (1979). Review of the geomagnetic secular variations on the historical time scale. Physics of the Earth and Planetary Interiors, 20(2-4), 83-95. https://doi.org/10.1016/0031-9201(79)90030-X Yukutake, T., Shimizu, H. (2015). Drifting and standing fields in the geomagnetic field for the past 400 years. Physics of the Earth and Planetary Interiors, 248, 63-72. https://doi.org/10.1016/j.pepi.2015.08.003 Yukutake, T., Shimizu, H. (2016). On the latitude dependence of drift velocity of the geomagnetic main field and its secular variation. Physics of the Earth and Planetary Interiors, 257, 28-39. https://doi.org/10.1016/j.pepi.2016.05.002 Yukutake, T., Tachinaka, H. (1969). Separation of the earth's magnetic field into the drifting and the standing parts. Bulletin of the Earthquake Research Institute, 47, 65-97. Yukutake, T., Shimizu, H. (2018). On the geomagnetic secular variation in the Pacific region. Physics of the Earth and Planetary Interiors, 283, 122-130. https://doi.org/10.1016/j.pepi.2018.08.008 Zhang, K., Liao, X. (2017). Theory and Modeling of Rotating Fluids: Convection, Inertial Waves and Precession. New Youk, NY: Cambridge University Press. | |
| dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/62983 | - |
| dc.description.abstract | 我們利用 IGRF 模型提供的高斯係數，分析1900年至2020年的全球磁場長期變化。(i) 我們應用經驗正交函數法 (Empirical Orthogonal Functions, EOF) 在球諧函數階數至6的全球磁場上，並在地函為絕緣的假設下，向下恢復磁場至核幔邊界 (Core-mantle boundary, CMB)。前三個EOF模式呈現週期分別約為120、75及60年的時間變化及對應的空間特徵。這些振盪模式潛在支持接近外核CMB的穩定分層中，流體受磁力、浮力、科氏力造成的 MAC (Magnetic, Archimedes and Coriolis) 波動行為 (Buffett, et al., 2016)。(ii) 我們採用和 Yukutake 與 Shimizu (2015) 類似的方法，根據高斯係數的變化軌跡將全球磁場分解成穩定項和移動項，再利用複數EOF (Complex EOF, CEOF) 分析移動項磁場。結果顯示在研究時間區段內繞轉部分週期的西移現象。本研究呈現完整的分析，為將來低階的長期磁場變化提供更進一步的地球物理解釋基礎。 | zh_TW |
| dc.description.abstract | We examine the variations of the global geomagnetic field on long temporal scales using the IGRF model given in the Gauss coefficients for 1900 - 2020. (i) We apply the Empirical Orthogonal Function (EOF) analysis to the geomagnetic field truncated at spherical-harmonic degree 6, and downward continue it to the core-mantle boundary (CMB) under the assumption of an insulating mantle. The first three EOF modes show the periods around 120, 75 and 60 years. With corresponding spatial structures, these standing-oscillational modes potentially support the manifestation of the so-called MAC (magnetic, Archimedes and Coriolis) waves in the stably stratified layer near CMB (Buffett et al., 2016). (ii) We also model and decompose the geomagnetic field to standing and drifting components according to trajectories of the corresponding Gauss coefficients similarly as Yukutake and Shimizu (2015). We then use the Complex EOF (CEOF) analysis on the drifting field. The results indicate the presence of the westward drift phenomenon but only weakly, given the fact that the westward drift has only completed a fraction of a cycle during the studied timespan. This work represents the most updated complete analysis, and lends an insightful basis for further studies for geophysical interpretations, of the low-degree geomagnetic variations of long temporal scales. | en |
| dc.description.provenance | Made available in DSpace on 2021-06-16T16:17:30Z (GMT). No. of bitstreams: 1 ntu-109-R05224107-1.pdf: 8807741 bytes, checksum: 87cb060fe67d810371eec51856159fab (MD5) Previous issue date: 2020 | en |
| dc.description.tableofcontents | 誌謝 (i) 中文摘要 (iii) ABSTRACT (iv) CONTENTS (v) LIST OF FIGURES (vii) LIST OF TABLES (xi) Chapter 1 Introduction (1) Chapter 2 Review of Geomagnetic Variations (3) Chapter 3 Theory (15) 3.1 Fundamental Equations of MHD (15) 3.1.1 The pre-Maxwell Equations (16) 3.1.2 Induction Equation (18) 3.1.3 Frozen-Flux Theorem (19) 3.1.4 Lorentz Force and Alfvén Waves (21) 3.2 Representation of the Geomagnetic Field (23) 3.2.1 Potential Field (23) 3.2.2 Downward Continuation (25) 3.2.3 Toroidal-Poloidal Decomposition (26) 3.3 Fluid Motions in Outer Core (27) 3.3.1 Wave Models (28) 3.3.2 Flow Models (40) Chapter 4 Data Processing and Methodology (45) 4.1 The IGRF model (45) 4.1.1 The Mean Field (49) 4.1.2 The Secular Field (49) 4.2 The g-h Diagram – Pairs for Drifting Field (52) 4.3 Empirical Orthogonal Functions (EOF) (58) 4.4 Complex Empirical Orthogonal Functions (CEOF) (62) 4.5 Procedure Summary (63) Chapter 5 Results (65) 5.1 EOF modes (65) 5.2 CEOF modes (71) 5.3 Latitude-dependent of the WD group velocity (71) Chapter 6 Discussion and Conclusions (79) APPENDIX (85) A. Governing Equations of Fluid Motions (85) A.1 Boussinesq Approximation (85) A.2 Linearization of Governing Equations for Hydromagnetic Waves (86) B. Derivation of the Geomagnetic Field (88) REFERENCE (91) | |
| dc.language.iso | en | |
| dc.title | 全球磁場變化分析：應用經驗正交函數法 | zh_TW |
| dc.title | Analysis of Geomagnetic Variability by Empirical Orthogonal Functions | en |
| dc.type | Thesis | |
| dc.date.schoolyear | 108-2 | |
| dc.description.degree | 碩士 | |
| dc.contributor.oralexamcommittee | 譚諤(Eh Tan),洪淑蕙(Shu-Huei Hung) | |
| dc.subject.keyword | 地球磁場長期變化,經驗正交模式,MAC 波動,西移,地核運動機制, | zh_TW |
| dc.subject.keyword | Geomagnetic variations,Empirical orthogonal functions,MAC waves,Westward drift,Core dynamics, | en |
| dc.relation.page | 99 | |
| dc.identifier.doi | 10.6342/NTU202000867 | |
| dc.rights.note | 有償授權 | |
| dc.date.accepted | 2020-05-25 | |
| dc.contributor.author-college | 理學院 | zh_TW |
| dc.contributor.author-dept | 地質科學研究所 | zh_TW |
| 顯示於系所單位： | 地質科學系 | |
文件中的檔案：
| 檔案 | 大小 | 格式 | |
|---|---|---|---|
| ntu-109-1.pdf 目前未授權公開取用 | 8.6 MB | Adobe PDF |
系統中的文件，除了特別指名其著作權條款之外，均受到著作權保護，並且保留所有的權利。