台中都會區為台灣第三大都會區，近年來隨著都市計劃的更新，人口以及都市化的程度有越來越高的趨勢，伴隨而來的空氣污染問題也逐漸受到重視。另外，根據碳監控行動組織(Carbon Monitoring for Action, CARMA)最新資訊顯示，台中擁有全世界二氧化碳排碳量位居第一的台中燃煤火力發電廠，以及排名世界第五的麥寮發電廠，因此更容易有高污染事件日之發生。其中台中縣大里地區因常發生熱島現象，空氣品質也較其他地區為差，特別是在秋季最為明顯，因此希望藉由本研究來分析探討造成大里地區秋季高污染事件的原因。本研究收集統計台灣環保署中部地區環境監測站、中央氣象局氣象監測站以及台中縣環保局自設測站的氣象及污染物資料，對於中部地區海陸風與都市熱島現象做分析探討。案例日期分別選取2007年與2008年秋季10月25日至10月30日期間，並利用澳洲CSIRO的TAPM (The Air Pollution Model)空氣污染模式作模擬分析評估。並進一步利用通風指數來評估探討中部地區混合層高度對於空氣品質劣化之影響。研究結果顯示，海陸風現象以及都市熱島效應皆是造成中部地區空氣品質變差的原因之一，而大里地區為案例期間台灣中部都會區的熱島中心，經由統計分析後發現，近兩年中部地區強熱島現象以及海陸風現象最為明顯的季節是在秋季，而高臭氧事件日同樣是以秋季發生頻率較高，顯示海風環流以及熱島效應會對臭氧濃度的累積造成一定程度的影響。另外，利用通風指數探討混合層高度對於臭氧濃度累積的結果顯示，當白天高臭氧污染事件發生時，通風指數確實有明顯之下降，不利於污染物之擴散。在模式模擬部分，模式在水平溫度場模擬值與實際監測值呈現良好的一致性，IOA值與相關係數皆接近0.9，且氣塊順逆軌跡研究可以準確解析污染物的傳輸路徑，以及熱島效應的影響，未來可以善加利用。 The Taichung metropolis is Taiwan’s third-largest metropolitan area. In recent years the process of urbanization and industrialization has produced air pollution problem in most metropolitan areas worldwide. Also, according to the information from Carbon Monitoring for Action (Carbon Monitoring for Action, CARMA) shows that Taichung power plants has the first carbon dioxide emissions of the world and the Mai-Liao Power Plant has the fifth carbon dioxide emissions of the world. In addition, the UHI phenomena and air pollution episodes are usually happened in Dali in central Taiwan in autumn. In this study, the aim of this study was to explore the reasons of high ozone episodes in Dali in autumn.<br>The meteorological and air pollutants data from government-owned observation stations and vertical atmosphere profiles obtained from tethersonde system were used to simulate by the air pollution model (TAPM) and analyze the association between the sea breeze and urban heat island phenomenon in central Taiwan during the period of 25-30 October 2007 and 25-30 October 2008. And then further use the ventilation index to analysis the association between the air pollutants and the mixing heights in central Taiwan.<br>The result shows the sea breeze and urban heat island phenomenon is one of the reasons that caused deterioration of air quality in central Taiwan. And the heat island center was in Dali during the period. The statistical analysis of nearly two years shows the strong urban heat island and the sea breeze phenomenon happened most obvious in autumn, while the high ozone episodes are also high frequency at the same time. For the reason that shows the sea breeze phenomenon and urban heat island will cause the accumulation of the ozone concentration. In addition, use the ventilation index to analysis the association between the air pollutants and the mixing height in central Taiwan. The result shows when the high ozone episode happens, the ventilation index actually decreases and the air pollutants are diffused weakly. In the model simulations, model simulated temperature field in the level of actual monitoring data showed good agreement, IOA values and correlation coefficients are close to 0.9. The trajectory by TAPM could accurately to analysis of the transmission path of air pollutants and the heat island effect.<br>
