2003-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/692911摘要：本計畫為“颱風重點研究”整合計畫之－子計畫，計畫目標為針對形成於台灣臨近海域（主要是南海）的颱風（或熱帶氣旋），分析其氣候特性、路徑和環流特徵，並利用 MM5模擬颱風形成過程中，環流和系統之中尺度結構變化，探討影響颱風形成之重要物理機制。整體計畫為期兩年，本計畫為第一年。 統計結果顯示，在1950～2001年間，平均每年有4.1個熱帶氣旋於南海地區形成（西北太平洋約為27個）；其中有17.3％形成於梅雨季，此比率顯著高於西北太平洋地區之9.5％。在2002年梅雨季，有兩個熱帶氣旋在南海北部之滯留鋒面上形成；之後向偏東北向移動且很快即影響台灣地區。一個形成於五月且僅維持熱帶低壓強度（TD06），而另一個形成於六月且發展至熱帶風暴（TS）強度（諾古力颱風，Noguri）。本研究將模擬和分析此兩系統的形成過程，並以此兩系統為例，探討在斜壓環境中熱帶氣旋之形成過程。在進行分析時，除採用EC網格資料外，亦將採用QuikSCAT風場資料，以瞭解系統形成時之中尺度與環境風場變化特徵。 除個案之分析模擬外，本計畫亦將分析、比較不同季節於南海形成颱風之環境特徵，分析時將畫分梅雨期（五、六月），中期（<br> Abstract: This is a sub-project of the Typhoon Integrated Project. Purpose of this project is to study the climatological aspect, the track pattern and the surrounding circulation features for those typhoons (or tropical cyclones) formed near Taiwan, especially in South China Sea (SCS). In addition, the evolution of mesoscale structures of the system and the environmental circulation pattern will be simulated using MM5. The important mechanisms leading to tropical cyclone formation will be discussed. The whole project will take two years and this is the first year of the project. Statistics show that during 1950-2001, there were about 4.1 tropical cyclones formed in SCS each year (about 27 for the western North Pacific). Among these systems, 17.3% formed during the Mei-yu season. This percentage is much higher than the 9.5% for the western North Pacific basin (east of 120o E). In 2002, there were two tropical cyclones formed on stationary fronts located at the northern part of SCS. These two systems moved northeastward and affected Taiwan area shortly after they formed. One system formed in late May and only maintained as a tropical depression (TD06). The other formed in early June and reached tropical storm (Typhoon Noguri) intensity. In this study, the formation process of these two systems will be simulated and analyzed. The tropical cyclone formation in a baroclinic environment will be discussed based on the study of these two cases. In our analysis, we will also use the QuikSCAT data as well as the EC grid-point data to analyze the evolution of the mesoscale features of the system and the environmental circulation pattern during the formation process. Besides the case study, the environmental circulation pattern during tropical cyclone formation in SCS for different periods will also be analyzed and discussed. Three periods will be considered in the analysis, the Mei-yu period (May and June), the middle period (July-September) and the late period (October-December). In addition, we will continue our previous study to examine the change in the mesoscale structure of a tropical cyclone during the formation stage using the QuikSCAT data. The role of the trade wind surges, the颱風颱風形成數值模擬QuikSCATTyphoonTyphoon FormationNumerical SimulationQuikSCAT