講演情報
[AAS08-P17]Vertical distribution of volatile organic compounds, NO2, and O3 at the Tall Tower in Incheon, Korea
*Hajung Kim1、Seora Woo1、Gangnam Cho2、 Rani Jung2、Yongjoo Choi1 (1.HUFS、2.NIER)
キーワード：
VOCs、OFP、Vertical distribution、NO2
Volatile organic compounds (VOCs) are emitted from both natural and anthropogenic sources and act as key precursors for the formation of secondary organic aerosols (SOA) and ozone (O3) through atmospheric photochemical reactions. Previous studies have been predominantly conducted at the ground level; thus they are insufficient to fully characterize the vertical distributions of O3, NO2, and VOCs, as well as the vertical contribution of their precursors in urban area. Therefore, the investigation of the vertical distributions for ozone and its precursors is essential for understanding ozone formation and behavior in urban areas. In this study, using passive samplers, the vertical distributions of VOCs, NO2, and O3 were measured at one-week intervals for a total of 19 weeks from May to October 2025 at four height levels (10, 58, 153, and 305 m) at POSCO Tower-Songdo (37.39 deg N, 126.64 deg E, 305 m) in Incheon, Korea. VOC samples were collected using FLM Carbopack X deactivated thermal desorption tubes (Sigma-Aldrich Supelco), and 53 out of the 57 target PAMS compounds were analyzed by Thermal Desorption-Gas Chromatography/Flame Ionization Detection (TD-GC/FID). Using maximum incremental reactivity (MIR), we assessed the ozone formation potential (OFP) of VOCs. O3 was sampled using cartridge RAD172, while NO2 was collected using cartridge RAD166 and analyzed by ultraviolet spectrophotometry (Shimadzu UV-1280). O3 concentrations generally increased with altitude, and vice versa for NO2. VOC concentrations were highest at 58 m. Among VOC chemical groups, alkanes exhibited the highest concentrations, followed by aromatics and alkenes, and the OFP showed the same order. This study will provide identification of priority VOC groups for ozone mitigation policy based on altitude-resolved observations at urban tall tower.