在2008年5月30日，一道梅雨鋒面系統經過台灣，為台灣北部帶來豪雨，31日，台灣西側生成一個對流系統，並慢慢地隨著鋒面的尾端朝東南方進入台灣內陸，沿途中不斷的增強，並在屏東北部山區造成強降雨，時雨量達40mm/hr，隨後便隨著鋒面移出台灣，且衰弱消失。此篇論文利用WRF模式來探討台灣地形對此對流系統之生成、增強以及其伴隨之降雨極值位置的影響。本研究利用不同地形高度的敏感度實驗來驗證台灣地形對對流系統發展的作用，包含CTRL run（full -terrain）、HTRN run（half -terrain）、及NTRN run（no-terrain）等三種不同地形高度的敏感度模擬實驗。
根據CTRL run（FR≒0.4）模擬結果發現，系統生成初期之對流系統的生成與台灣地形密切相關，由於台灣南方之西南風受到中央山脈阻擋之影響，使得氣流無法過山，因此產生往北繞山的風場，此氣流與北方之東北風在台灣中部沿海形成氣旋式渦旋，並在原地停留一至兩小時，隨後便形成對流系統。因此在地形敏感度實驗中，隨著台灣地形高度降低，由於西南風受到中央山脈的影響變小，使得向北繞山的氣流比CTRL run弱，因此對流系統生成位置偏向較內陸，甚至當地形去除後此對流系統便無法形成。另外根據模式模擬的結果也發現，由於對流系統在進入內陸後，繞山之氣流與台灣海峽上之北風仍不斷輻合，使對流系統在進入內陸後持續增強成大範圍之對流系統，此輻合不斷地提供有利於對流系統發展之不穩定的環境，對於對本個案之對流系統的增強及維持相當重要，之後由於鋒面離開台灣，全台風向皆轉為東北風，此對流系統才逐漸消散。在HTRN run （FR≒0.8）中，由於氣流大部分皆可過山，使得往北的繞山氣流變弱，同時鋒面受到地形的影響也減弱，造成對流系統移進內陸後，強度無法繼續維持。而在HTRN run中，屏東仍然有產生降雨極值，位置較CTRL run南邊，其形成原因主要來自鋒面本身的輻合，而非地形之阻擋與抬升作用，因此當地形去除後，雖然本個案所探討之對流系統無法生成，但在台東附近仍然有降雨產生，形成的主因也是由鋒面本身的輻合所造成，且因少了中央山脈的影響，鋒面移速較HTRN run更快，位置也較HTRN run東邊。

In May 30, 2008, a Mei-Yu Front system passed over Taiwan, bringing heavy rainfall to northern Taiwan. In May 31, a convective cell was generated at western Taiwan. This convective system associated with the front to move into Taiwan area. It caused heavy rainfall and the maximum rainfall rate reached 40mm/hr in the mountains area of northern Pingtung. Later, this system moved out of Taiwan accompanied with the front and dissipated, gradually. This study uses WRF model to investigate how the terrain of Taiwan influence on the generation and enhancement of the convective cell and the movement of the extreme rainfall location. In this study, several sensitivity experiments with different terrain heights of Taiwan are performed to verify the impact of terrain on the development of convective system. The sensitive tests contain three different terrain heights including CTRL run (full-terrain), HTRN run(half-terrain), and NTRN run(no-terrain).
The results of CTRL run(FR ≒ 0.4) show that the formation of this convective system is closely related to terrain effects. The airflow was blocked by the Taiwan Central Mountain Range, so that the wind direction was changed from southwestly to southly and converges with the frontal northeasterly and provide favorable condition for the formation of the convective system. When the terrain height is reduced, the generation location of convective system moves into inland. If the terrain is removed, the convective cell will be not generated.
After the convective system moved into the inland area, the southly airflow resulted from the blocking effects of Taiwan terrain continuously converge with the northly. This convergence provide a favorable condition for the enhancement and maintain of the the convective system. The rainfall maximum was located at the windward slope. However, in the HTRN experiment, the southly wind resulted from the terrain blocking effect became weak due to the terrain height is reduced to the half. The intensity of the convective system can not be maintained when it moved into the island area.

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