충청권 PM2.5 국지적 변동성의 공간상관성 분석

Abstract

Particulate air quality in the Chungcheong Area, mainly covering Chungcheongnam-do, Chuncheongbuk-do, Daejeon, and Sejong, is intricately influenced by regional transport from the Seoul Metropolitan Area and long-range transport from China of particulate matter (PM) and precursors, as well as local emissions originating from coal-fired power plants, petrochemical and industrial complexes, steelworks, and livestock farms along its western coasts. Consequently, concerns arise regarding the impact of these local emissions on PM air quality in inland cities within the Chungcheong Area. However, the relationships within the area concerning the variability of PM between the western source area and the inland cities have not been revealed. This study investigates spatial ranges sharing local variability in PM2.5 at the five coastal nearsource sites, including the Pyeongtaek-hang site adjacent to Dangjin, and the five inland cities in the Chungcheong Area for the years 2021~2022. To isolate local variability from regional fluctuations related to long-range transport, secondary production, accumulation, and ventilation driven by synoptic meteorology, spatial deviation from the spatial mean PM2.5 concentration was utilized. The results indicate that the local variability of PM2.5 in the northwestern coastal sites (Dangjin, Pyeongtaek, Seosan) does not show a significant correlation (p<0.01) with that of the inland cities. On the other hand, the western coastal sites (Taean, Boryeong) exhibit some degree of correlation (R>0.4) with the southeastern inland cities. Inorganic and carbonaceous PM2.5 species at Seosan show little correlation with other sites in the Chungcheong Area, except for sulfate and nitrate at Dangjin. This study underscores the necessity to treat the western coastal area and inland area of the Chungcheong Area as distinct entities in future PM air quality management efforts.