空氣污染一直是大家所重視的議題，近年來大家多關注在PM2.5上，也因為近年來的管制其事件日有下降的趨勢，故須針對另一污染物臭氧來進行形成機制的解析及實質上的管制，本研究使用HYSPLIT搭配WRF三維氣象場針對2016年臭氧八小時事件日進行逆軌跡分析，後續由TEDS10排放量模擬進行污染源管制策略的擬定。
從指標污染物統計來看，101<AQI<150區間中，O3_8hr事件日由24%上升至66%，而151<AQI<200區間中則由35%上升至95%，AQI>200之區間則全部都是O3_8hr事件日，這邊顯示了臭氧污染應不可忽視；而針對2016年O3_8hr事件日之臭氧逐時濃度分析後可發現臭氧峰值多發生在每天的12~14時，其中也發現了各測站臭氧變化具有”非單峰”現象，整體非單峰比例為33%~100%，比較了中國沿海地區的城市及美國南加州測站可發現其”非單峰”比例分別為31%及37%，並沒有像台灣地區那麼高，這也有可能為台灣臭氧事件日之原因。
統整全部測站的峰所發生之時間點後，使用HYSPLIT軌跡模式可以獲得這些峰值氣團來源方向及趨勢，可以發現各測站同一天之峰值軌跡大多類似，中南部地區之軌跡多為東北風沿著西邊海岸進入到各測站，北部及竹苗地區則也同樣也受到東北風之影響，其中也有許多從南邊來之氣團及環流類型的軌跡，這些臭氧峰值多半為”傳輸”所造成，即在進到測站前一小時前就有較高的臭氧濃度，由軌跡我們可以回推至當天早上以獲得NMHC/NOx數值來計算EKMA所需數值，各空品區皆顯示NOx及VOCs皆需要管制之比例最高，但這並沒有達到我們的目的。
利用TEDS10進行模式模擬各縣市對於各測站污染源之影響及台灣境外所造成之影響，針對區域間臭氧多測站超標事件日可以發現2016/4/29及2016/8/29這兩天主要為台灣境外所造之影響佔90%以上，而其他事件日中可以看到很明顯的NOx之影響比例比VOCs大約1.2~13倍，若細分為點、線、面污染源，各縣市則必須先管制線源之NOx，後續再管制點源NOx，這樣可期望降低台灣臭氧事件日的發生。

From the statistics of 2016~2020 indicator pollutants, in the interval of 101<AQI<150, O3_8hr events increased from 24% to 66%, while in the interval of 151<AQI<200, it increased from 35% to 95%, and in the interval of AQI>200, All are O3_8hr events, which shows that ozone pollution should not be ignored.After analyzing the hourly concentration of ozone on the O3_8hr event day in 2016, it can be found that ozone peaks mostly occur between 12 and 14 o’clock each day. The ozone concentration has a "non-single peak" phenomenon, and the phenomenon in each station ratio is 33% to 100%. Comparing the cities in coastal areas of China and the Southern California station in the United States, it can be found that the "non-single peak" ratio is 31% and 37% respectively.It is not as high as in Taiwan. This may also be the cause of the ozone events in Taiwan.
The HYSPLIT trajectory mode can be used to obtain the source direction and trend of these ozone peaks air parcels. It can be found that the peak trajectories of all stations on the same day are mostly similar, and the trajectories in the central and southern regions are mostly northeast winds,entering the stations along the west coast.The north and Zhumiao areas are also affected by the northeasterly wind. There are many air masses and circulation types from the south. These ozone peaks are mostly caused by "transport".It means that there was a higher ozone concentration one hour before entering the station. From the trajectory, we can go back to the morning to obtain the NMHC/NOx value to calculate the required value for EKMA. Each area shows both control NOx and VOCs.
We use TEDS10 to simulate the impact of counties and cities on the pollution sources of each station and the impact outside Taiwan. For the regional events , it can be found that the two days of 2016/4/29 and 2016/8/29 are mainly caused by outside Taiwan accounts for more than 90% station. It is obvious that the impact ratio of NOx is about 1.2~13 times that of VOCs. If it is subdivided into point, line, and area pollution sources, each county and city must control the NOx from the line source first, and then control the NOx from the point source, so that it can be expected to reduce the occurrence of ozone incidents in Taiwan.

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