臺灣博碩士論文加值系統

本研究利用2007~2018年的ASCAT (The first Advanced Scatterometer)衛星觀測資料、重建西北太平洋地區之颱風近地表風場結構，並分析颱風壯度(strength，定義為100~300公里之平均角動量)。結果顯示，颱風之環境濕度越高，越有利颱風壯度增加；而環境垂直風切較高，則不利壯度增加。將颱風壯度變化前10%定義為快速擴張(rapid expansion , RE)，合成分析結果顯示，RE個案明顯位於季風距平環境中，而颱風之西南方則有強烈的低層西南風帶來水氣，增高中層溼度。此外，RE個案南方有強烈的高層輻散區；而衛星觀測亦顯示，RE颱風南方有較多的降雨。角動量流之分析結果顯示，在850百帕高度、RE個案於颱風外核區外，有相較於其他個案更多的角動量入流。另一方面，快速增強(RI)颱風則明顯位於東風距平環境；颱風東北邊之中層溼度較低，可抑制颱風外核區域之降雨，使降雨集中在颱風中心。
分析結果同時顯示，颱風西南側中層溼度、南側高層輻散及西南側降雨和颱風壯度變化之相關性達0.4以上，顯示颱風西南部非軸對稱降雨對颱風結構變化具重大影響。中心西南部環境溼度較低的颱風個案，則需要較高的初始壯度才能到達RE。整體而言，颱風西南象限環境中層濕度，對於颱風是否出現RE的影響，大於其他區域環境濕度。

This study uses ASCAT (The first Advanced Scatterometer) data from 2007 to 2018 to rebuild tropical cyclone (TC) symmetry surface wind structure. The TC strength is defined as average angular momentum between 100 to 300 km, calculated from our dataset. Results show that TC strength is less related to TC intensity but highly related to TC size. The environmental humidity favors strength development, but vertical wind shear is not. The first 10% of strength change per day is defined as rapid expansion (RE). The reanalysis data composite shows that RE cases are in a monsoon environment with a strong low-level southwest wind, high mid-level humidity, and high-level divergence in the southwest of TC. CMORPH data also shows that RE cases have more precipitation in the southwest than others. As a result, RE cases have significant angular momentum inflow outside TC outer-core. In contrast, rapid intensification (RI) cases are in the easterly environment, with low humidity in the northeast and less precipitation in the outer core.
Mid-level humidity, high-level divergence, and precipitation in the southwest or south area all have over 0.4 correlation coefficients with TC strength. This result shows that asymmetry convection in the southwest can contribute to symmetry TC structure. Besides, cases with lower southwest humidity need higher strength to reach RE.

致謝 i
摘要 ii
Abstract iii
目錄 iv
表目錄 vi
圖目錄 vii
一、 前言 1
1.1 背景回顧 1
1.2 研究動機與目的 3
二、 使用資料說明與颱風風場重建方法 6
2.1使用資料說明 6
2.2 風場重建方法 8
2.2.a 環境風場計算 10
2.2.b 颱風軸對稱風場回歸計算 10
2.2.c 颱風暴風半徑(R15)計算 12
三、 颱風低層風場結構資料庫建置 13
3.1 投落送觀測資料重建之颱風結構 13
3.1.a 投落送資料處理與颱風結構重建細節 13
3.1.b Dropsonde-based颱風結構分析 14
3.2 ASCAT資料重建之颱風結構 15
3.2.a ASCAT資料個案篩選與颱風結構重建細節 15
3.2.b ASCAT-based颱風結構與暴風半徑資料分析 16
3.3 本研究所分析之颱風暴風半徑與其他機構者之比較 17
四、 颱風結構特性與其變化之分析 19
4.1 颱風壯度之特性分析 19
4.1.a颱風壯度定義 19
4.1.b 颱風壯度之特性分析 20
4.1.c 颱風結構快速變化之分類與特性 21
4.2 快速擴張(RE)與快速增強(RI)颱風之環境差異 23
4.2.a ERA5大氣環境參數 23
4.2.b CMORPH降雨 25
4.2.c 角動量通量 26
4.2.d 垂直風切與低層平均流 27
4.2.e 海平面溫度 28
4.3 不對稱環境參數對颱風快速擴張影響之探討 29
4.3.a 參數影響範圍設定 29
4.3.b 環境參數結果討論 30
4.3.c 不同象限中層濕度對RE之影響 31
五、 討論與總結 33
5.1 個案之初步分析 34
5.2 討論 36
5.3 結語 39
參考資料 40
表 45
圖 48

辛在勤, 2010: 天然災害災防問答集. 臺北市: 交通部中央氣象局.
李清勝, 陳佳莉, 2019：颱風強度及暴風圈預報技術開發(2/2). 交通部中央氣象局委託研究計畫, MOTC-CWB-108-M-01, 120 p.
周昆炫, 吳聖宇, and 林書正, 2018: 颱風壯度與大小對台灣風雨之影響. 大氣科學, 46, 222-246.
郭昱德, 2020: 低層平均流場對颱風初期發展之影響, 大氣科學研究所, 國立臺灣大學, 63p.
黃麗蓉, 2001: 信風爆發對熱帶氣旋形成之影響, 大氣科學研究所, 國立臺灣大學, 105p.
Brennan, M. J., C. C. Hennon, and R. D. Knabb, 2009: The Operational Use of QuikSCAT Ocean Surface Vector Winds at the National Hurricane Center. Wea. Forecasting, 24, 621-645.
Carr III, L. E., and R. L. Elsberry, 1995: Monsoonal interactions leading to sudden tropical cyclone track changes. Mon. Wea. Rev., 123, 265-290.
Challa, M., and R. L. Pfeffer, 1980: Effects of eddy fluxes of angular momentum on model hurricane development. J. Atmos. Sci., 37, 1603-1618.
Chan, K. T. F., and J. C. L. Chan, 2012: Size and Strength of Tropical Cyclones as Inferred from QuikSCAT Data. Mon. Wea. Rev., 140, 811-824.
——, and ——, 2013: Angular Momentum Transports and Synoptic Flow Patterns Associated with Tropical Cyclone Size Change. Mon. Wea. Rev., 141, 3985-4007.
Chavas, D. R., and K. A. Emanuel, 2010: A QuikSCAT climatology of tropical cyclone size. Geophys. Res. Lett., 37, L18816.
——, N. Lin, and K. A. Emanuel, 2015: A Model for the Complete Radial Structure of the Tropical Cyclone Wind Field. Part I: Comparison with Observed Structure*. J. Atmos. Sci., 72, 3647-3662.
Chen, B.-F., C.-S. Lee, and R. L. Elsberry, 2014: On tropical cyclone size and intensity changes associated with two types of long-lasting rainbands in monsoonal environments. Geophys. Res. Lett., 41, 2575-2581.
——, C. A. Davis, and Y.-H. Kuo, 2018: Effects of Low-Level Flow Orientation and Vertical Shear on the Structure and Intensity of Tropical Cyclones. Mon. Wea. Rev., 146, 2447-2467.
——, 2019a: An Idealized Numerical Study of Shear-Relative Low-Level Mean Flow on Tropical Cyclone Intensity and Size. J. Atmos. Sci., 76, 2309-2334.
——, B. Y. Chen, H. T. Lin, and R. L. Elsberry, 2019b: Estimating Tropical Cyclone Intensity by Satellite Imagery Utilizing Convolutional Neural Networks. Wea. Forecasting, 34, 447-465.
Chen, D. Y.-C., K. K. W. Cheung, and C.-S. Lee, 2012: A Study on the Synoptic-Dynamical Characteristics of Compact Tropical Cyclones in the Western North Pacific. Mon. Wea. Rev., 140, 4046-4065.
Cocks, S. B., and W. M. Gray, 2002: Variability of the Outer Wind Profiles of Western North Pacific Typhoons: Classifications and Techniques for Analysis and Forecasting. Mon. Wea. Rev., 130, 1989-2005.
Davis, C., C. Snyder, and A. C. Didlake Jr, 2008: A vortex-based perspective of eastern Pacific tropical cyclone formation. Mon. Wea. Rev., 136, 2461-2477.
Dunion, J. P., C. D. Thorncroft, and C. S. Velden, 2014: The Tropical Cyclone Diurnal Cycle of Mature Hurricanes. Mon. Wea. Rev., 142, 3900-3919.
Dvorak, V. F., 1975: Tropical cyclone intensity analysis and forecasting from satellite imagery. Mon. Wea. Rev., 103, 420-430.
Emanuel, K., C. DesAutels, C. Holloway, and R. Korty, 2004: Environmental Control of Tropical Cyclone Intensity. J. Atmos. Sci., 61, 843-858.
——, 1986: An Air-Sea Interaction Theory for Tropical Cyclones. Part I: Steady-State Maintenance. Journal of Atmospheric Sciences, 43, 585-605.
——, 1988: The Maximum Intensity of Hurricanes. Journal of Atmospheric Sciences, 45, 1143-1155.
Figa-Saldaña, J., J. J. Wilson, E. Attema, R. Gelsthorpe, M. R. Drinkwater, and A. Stoffelen, 2002: The advanced scatterometer (ASCAT) on the meteorological operational (MetOp) platform: A follow on for European wind scatterometers. Can. J. Remote Sens., 28, 404-412.
Frank, W. M., 1982: Large-scale characteristics of tropical cyclones. Mon. Wea. Rev., 110, 572-586.
——, and E. A. Ritchie, 2001: Effects of Vertical Wind Shear on the Intensity and Structure of Numerically Simulated Hurricanes. Mon. Wea. Rev., 129, 2249-2269.
Franklin, J. L., M. L. Black, and K. Valde, 2003: GPS Dropwindsonde Wind Profiles in Hurricanes and Their Operational Implications. Wea. Forecasting, 18, 32-44.
Fu, B., M. S. Peng, T. Li, and D. E. Stevens, 2012: Developing versus Nondeveloping Disturbances for Tropical Cyclone Formation. Part II: Western North Pacific. Mon. Wea. Rev., 140, 1067-1080.
Herndon, D., and C. Velden, 2008: CIMSS TC intensity satellite consensus (SATCON). 62nd Interdepartmental Hurricane Conference, Charleston, SC.
Hill, K. A., and G. M. Lackmann, 2009: Influence of Environmental Humidity on Tropical Cyclone Size. Mon. Wea. Rev., 137, 3294-3315.
Hersbach, H., and Coauthors, 2020: The ERA5 global reanalysis. Q. J. R. Meteorolog. Soc., 146, 1999-2049.
Holland, G. J., 1983: Angular momentum transports in tropical cyclones. Q. J. R. Meteorolog. Soc., 109, 187-209.
——, 1995: Scale interaction in the western Pacific monsoon. Meteorol. Atmos. Phys., 56, 57-79.
——, 1997: The Maximum Potential Intensity of Tropical Cyclones. J. Atmos. Sci., 54, 2519-2541.
——, and R. T. Merrill, 1984: On the dynamics of tropical cyclone structural changes. Q. J. R. Meteorolog. Soc., 110, 723-745.
Hsieh, Y.-H., C.-S. Lee, and C.-H. Sui, 2017: A study on the influences of low-frequency vorticity on tropical cyclone formation in the western North Pacific. Mon. Wea. Rev., 145, 4151-4169.
Knaff, J. A., and M. DeMaria, 2006: A multi-platform satellite tropical cyclone wind analysis system. AMS 14th Conference on Satellite Meteorology and Oceanography.
——, C. J. Slocum, K. D. Musgrave, C. R. Sampson, and B. R. Strahl, 2016: Using Routinely Available Information to Estimate Tropical Cyclone Wind Structure. Mon. Wea. Rev., 144, 1233-1247.
Kruk, M. C., K. R. Knapp, and D. H. Levinson, 2010: A Technique for Combining Global Tropical Cyclone Best Track Data. J. Atmos. Oceanic Technol., 27, 680-692.
Lee, C.-S., K. K. Cheung, W.-T. Fang, and R. L. Elsberry, 2010: Initial maintenance of tropical cyclone size in the western North Pacific. Mon. Wea. Rev., 138, 3207-3223.
——, 1989a: Observational analysis of tropical cyclogenesis in the western North Pacific. Part II: Budget analysis. J. Atmos. Sci., 46, 2599-2616.
——, 1989b: Observational Analysis of Tropical Cyclogenesis in the Western North Pacific. Part I: Structural Evolution of Cloud Clusters. J. Atmos. Sci., 46, 2580-2598.
Leppert, K. D., and D. J. Cecil, 2016: Tropical Cyclone Diurnal Cycle as Observed by TRMM. Mon. Wea. Rev., 144, 2793-2808.
Lin, Y., M. Zhao, and M. Zhang, 2015: Tropical cyclone rainfall area controlled by relative sea surface temperature. Nat Commun, 6, 6591.
Maclay, K. S., M. DeMaria, and T. H. Vonder Haar, 2008: Tropical Cyclone Inner-Core Kinetic Energy Evolution. Mon. Wea. Rev., 136, 4882-4898.
Martinez, J., C. C. Nam, and M. M. Bell, 2020: On the Contributions of Incipient Vortex Circulation and Environmental Moisture to Tropical Cyclone Expansion. Journal of Geophysical Research: Atmospheres, 125.
McBride, J. L., and R. Zehr, 1981: Observational Analysis of Tropical Cyclone Formation. Part II: Comparison of Non-Developing versus Developing Systems. J. Atmos. Sci., 38, 1132-1151.
Merrill, R. T., 1984: A Comparison of Large and Small Tropical Cyclones. Mon. Wea. Rev., 112, 1408-1418.
Miller, B. I., 1958: On the maximum intensity of hurricanes. J. Meteor., 15, 184-195.
Morris, M., and C. S. Ruf, 2017: Determining Tropical Cyclone Surface Wind Speed Structure and Intensity with the CYGNSS Satellite Constellation. J. Appl. Meteor. Climatol., 56, 1847-1865.
Olander, T. L., and C. S. Velden, 2007: The advanced Dvorak technique: Continued development of an objective scheme to estimate tropical cyclone intensity using geostationary infrared satellite imagery. Wea. Forecasting, 22, 287-298.
Powell, M. D., E. W. Uhlhorn, and J. D. Kepert, 2009: Estimating Maximum Surface Winds from Hurricane Reconnaissance Measurements. Wea. Forecasting, 24, 868-883.
Ricciardulli, L., and F. J. Wentz, 2016: Remote Sensing Systems ASCAT C-2015 Daily Ocean Vector Winds on 0.25 deg grid, Version 02.1, Santa Rosa, CA: Remote Sensing Systems. Available at www.remss.com/missions/ascat.
Ritchie, E. A., and G. J. Holland, 1999: Large-scale patterns associated with tropical cyclogenesis in the western Pacific. Mon. Wea. Rev., 127, 2027-2043.
Sampson, C. R., E. M. Fukada, J. A. Knaff, B. R. Strahl, M. J. Brennan, and T. Marchok, 2017: Tropical cyclone gale wind radii estimates for the western North Pacific. Wea. Forecasting, 32, 1029-1040.
Schenkel, B. A., N. Lin, D. Chavas, M. Oppenheimer, and A. Brammer, 2017: Evaluating Outer Tropical Cyclone Size in Reanalysis Datasets Using QuikSCAT Data. J. Clim., 30, 8745-8762.
Smith, R. K., and M. T. Montgomery, 2016: The efficiency of diabatic heating and tropical cyclone intensification. Q. J. R. Meteorolog. Soc., 142, 2081-2086.
Song, J., and P. J. Klotzbach, 2016: Wind structure discrepancies between two best track datasets for western north Pacific tropical cyclones. Mon. Wea. Rev., 144, 4533-4551.
Tao, D., and F. Zhang, 2014: Effect of environmental shear, sea-surface temperature, and ambient moisture on the formation and predictability of tropical cyclones: An ensemble-mean perspective. J. Adv. Model. Earth Syst., 6, 384-404.
Touma, D., S. Stevenson, S. J. Camargo, D. E. Horton, and N. S. Diffenbaugh, 2019: Variations in the Intensity and Spatial Extent of Tropical Cyclone Precipitation. Geophys. Res. Lett., 46, 13992-14002.
Tsuji, H., and K. Nakajima, 2019: Relationship Between the Change in Size of Tropical Cyclones and Spatial Patterns of Precipitation. Journal of Geophysical Research: Atmospheres, 124, 9948-9962.
Vickery, P. J., D. Wadhera, M. D. Powell, and Y. Chen, 2009: A Hurricane Boundary Layer and Wind Field Model for Use in Engineering Applications. J. Appl. Meteor. Climatol., 48, 381-405.
Weatherford, C. L., and W. M. Gray, 1988a: Typhoon structure as revealed by aircraft reconnaissance. Part I: Data analysis and climatology. Mon. Wea. Rev., 116, 1032-1043.
——, and ——, 1988b: Typhoon Structure as Revealed by Aircraft Reconnaissance. Part II: Structural Variability. Mon. Wea. Rev., 116, 1044-1056.
Wentz, F. J.,C. Gentemann, K.A. Hilburn, 2015a: Remote Sensing Systems TRMM TMI, 3-Day Environmental Suite on 0.25 deg grid, Version 7.1, Remote Sensing Systems, Santa Rosa, CA. Available online at www.remss.com/missions/tmi.
——, T. Meissner, J. Scott, K.A. Hilburn, 2015b: Remote Sensing Systems GPM GMI 3-Day Environmental Suite on 0.25 deg grid, Version 8.2, Remote Sensing Systems, Santa Rosa, CA. Available online at www.remss.com/missions/gmi.
Wong, M. L. M., and J. C. L. Chan, 2004: Tropical Cyclone Intensity in Vertical Wind Shear. J. Atmos. Sci., 61, 1859-1876.
Wu, C.-C., and Coauthors, 2005: Dropwindsonde observations for typhoon surveillance near the Taiwan Region (DOTSTAR). Bull. Am. Meteorol. Soc., 86, 787-790.