Pollution Characteristics of PM2.5 Measured during Fall at a Seosan Site in Chungcheong Province | |||||
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Writer | 관리자 | Date | 2021-04-14 10:28 | Hit | 181 |
Pollution Characteristics of PM2.5 Measured during Fall at a Seosan Site in Chungcheong Province Abstract In this study, chemical characteristics of PM2.5 collected between October 1 and November 4, 2019 at Chungcheong region air quality research center in Seosan, were studied to understand reasons leading to PM2.5 increases. 24-hr integrated PM2.5 samples were analysed for organic and elemental carbon (OC and EC), water-soluble OC (WSOC), and eight water-soluble inorganic ions. Over the study period, increase in PM2.5 concentration was attributed to enhancement of organic mass (OM=1.8×OC) and NO3- concentrations. Relationships of OC and WSOC with EC, K+, Cl-, and secondary NO3- showed good-to-strong correlations, suggesting primary emissions (e.g., traffic and biomass burning sources) and secondary organic aerosol (OA) formation contributed to WSOC and OC concentrations. Moreover, high WSOC/OC (mean: 0.54) and OC/EC (mean: 9.0) ratios support the existence of various OA sources at the site. Four PM2.5 pollution episodes (October, 10 (eventI), 17 (event II), 20~22 (event III), and November 02 (event IV)), which exceeded 24-hr PM2.5 Korean standard of 35 μg/m3, occurred and were related to concentration increases in OM and secondary ionic species. Based on synoptic weather patterns, PM2.5 forecast results, and air mass transport pathways, it was concluded that events I, II, and IV were significantly influenced by locally produced pollutions, while event III was impacted by both long-range transport of air pollutants and local emissions, with the highest concentration of SO42- (7.3 μg/m3). Among the four events, highest OM and NO3- concentrations were found in the events IV and III, respectively. Results from this study suggest that strategies to reduce nitrogen oxides and organic aerosols in the study region are formulated to control PM2.5 levels. Key words Chungcheong region, PM2.5 pollution events, Organic aerosols and NO3-, Biomass burning, Synoptic weather patterns, Local emissions ▶Sources : Journal of Korean Society for Atmospheric Environment
Vol. 36, No. 3, June 2020 |