隨著空氣污染防制政策持續推動，高屏空品區的空氣品質雖已逐漸改善，但根據2023年環境部年報統計，該區空氣品質指標(Air Quality Index， AQI)大於100之比例為全國各空品區最高，顯示空氣污染問題仍不容忽視。高屏地區受到工業活動密集、地形條件及氣象變化等因素影響，當地排放與區域傳輸相互作用，使污染物的累積與分布情形更為複雜。因此，本研究利用2024年2至3月美國太空總署(NASA)亞洲空氣品質飛航與衛星計畫(Airborne and Satellite Investigation of Asian Air Quality， ASIA-AQ)於台灣執行之飛航觀測資料，探討台灣西南部揮發性有機化合物(Volatile Organic Compounds， VOCs)三維空間分布及排放源特徵。 本研究選取密集觀測期IOP-1 (2/15)、IOP-3 (3/13)及IOP-4 (3/27)三次飛航觀測資料，依區域與高度進行比較，並結合VOCs濃度與物種組成、臭氧生成潛勢、苯/甲苯/乙苯(BTE)三者關係及特徵比值，分析不同氣團的污染來源與光化學特性，同時比較飛航觀測與地面測站及無人機觀測結果。臭氧生成潛勢分析結果顯示，烯類及芳香烴類雖非濃度占比最高的物種類別，但因具有較高的反應活性，對臭氧生成具有重要貢獻，其中芳香烴類於1000公尺以下的臭氧生成潛勢貢獻比例約為44-54%，顯示低層大氣中高反應性VOCs對臭氧生成潛勢具有關鍵影響。研究結果亦顯示，IOP-1與IOP-4期間，台灣西部飛航高度1000公尺以下之VOCs主要受交通排放影響，T/B比值多介於交通排放特徵範圍，IOP-1及IOP-4之平均值分別為1.68與2.19；部分市區及工業集中區則出現較高的VOCs與Ox濃度。相較之下，飛航高度1000公尺以上氣團呈現苯比例增加及汽油相關示蹤物濃度降低等特徵，表示其受近地面直接排放的影響較弱。此一特徵與東部地區的觀測結果相近，東部VOCs濃度及特徵比值整體較低且分布集中，兩者皆較接近區域背景或較老化氣團特徵。IOP-3期間不同高度與區域間的污染物差異較小，顯示大氣混合作用使污染物分布較為均勻。飛航觀測、地面測站(空氣品質監測站及光化學評估監測站)與無人機資料之比較顯示，地面測站與無人機較能反映鄰近排放源特徵，而飛航觀測則呈現較大空間尺度的污染分布與垂直變化，飛航低層觀測與鳳山及台南的地面站點結果較為相似，整體以交通排放特徵為主，而隨高度增加，當地排放特徵逐漸減弱。 整體分析結果可知，台灣南部VOCs的分布與來源會隨飛航期間、區域及高度而有所差異，低層大氣主要受到交通與工業排放影響，高層則較接近背景氣團。本研究透過飛航與地面觀測資料的整合，進一步建立污染物由近地面向高空延伸之分布特徵，並補足固定式測站在區域尺度與垂直觀測上的不足。;With the continued implementation of air pollution control policies， air quality in the Kao-Ping region (Kaohsiung and Pingtung) has gradually improved. However， according to the Ministry of Environment’s 2023 annual report， this region recorded the highest proportion of days with an Air Quality Index (AQI) above 100 among all regions in Taiwan， indicating that air pollution remains a significant concern. The Kao-Ping region is affected by intensive industrial activities， complex terrain， and variable meteorological conditions. The interaction between local emissions and regional transport further complicates the accumulation and spatial distribution of air pollutants. Therefore， this study used aircraft observations conducted over Taiwan from February to March 2024 as part of NASA ASIA-AQ campaign to investigate the horizontal and vertical distributions and source characteristics of VOCs over southern Taiwan. This study selected three intensive observation periods， IOP-1 (2/15)， IOP-3 (3/13)， and IOP-4 (3/27). The analysis integrated VOCs concentrations， ozone formation potential， benzene/toluene/ethylbenzene (BTE) ternary diagrams， and characteristic ratios to investigate the pollution sources and photochemical characteristics of different air masses. The aircraft observations were further compared with measurements from ground-based monitoring stations and UAV observations. The OFP analysis showed that alkenes and aromatic hydrocarbons， despite not being the most abundant VOC categories， were important contributors to ozone formation because of their high reactivity， with aromatic hydrocarbons contributing approximately 44–54% of the total OFP below 1000 m， indicating the key role of highly reactive VOCs in the lower atmosphere. During IOP-1 and IOP-4， VOCs below 1，000 m over western Taiwan were mainly influenced by traffic emissions， with T/B ratios mostly falling within the characteristic range of traffic-related sources and average values of 1.68 and 2.19， respectively. Elevated VOCs and Ox concentrations were also observed over some urban and industrial areas. In contrast， air masses above 1，000 m showed a higher benzene contribution and lower gasoline-related tracers， indicating weaker near-surface influences. These characteristics were similar to those over eastern Taiwan， suggesting more background-like or aged air masses. During IOP-3， pollutant distributions were more uniform across regions and altitudes， reflecting stronger atmospheric mixing. Comparisons among aircraft， ground-based， and UAV observations showed that ground-based and UAV measurements were more sensitive to nearby emission sources， whereas aircraft observations captured broader spatial and vertical variations. Low-altitude aircraft measurements were similar to those at the Fongshan and Tainan stations and were mainly characterized by traffic emissions， while local emission influences weakened with altitude. Overall， VOCs distributions and sources over southern Taiwan varied by flight period， region， and altitude. Lower-level air masses were mainly influenced by traffic and industrial emissions， whereas upper-level air masses were more background-like.
