Presentation Information
[AAS08-P16]Apportionment of primary and secondary carbonaceous aerosols in Seosan, suburban site, Korea in winter of 2026
*jiyoung Choi1, Seokjun Seo2, Greem Lee2, Yongseok jeon3, Yongjoo Choi1 (1.Department of Environmental Science, Hankuk University of Foreign Studies, Yongin, South Korea, 2.Air Quality Research Division, National Institute of Environmental Research, Incheon, Republic of Korea, 3.APM Engineering Co., Ltd., Seoul, Republic of Korea)
Keywords:
Carbonaceous aerosols,Primary and Secondary organic aerosol,Aethalometer,Total carbon analyzer
Carbonaceous aerosols (CA) comprise a large fraction of fine particulate matter (PM2.5) and exert a negative impact on public health and the Earth's radiative balance. However, the radiative effect of CA still remain uncertain because its strong light absorption by black carbon (BC) and the complex chemical and physical properties of organic aerosols (OA) undergoing diverse atmospheric secondary formation. Specifically, the coexistence of light-absorbing brown carbon (BrC) and non-absorbing OA fractions complicates the quantitative characterization of CA optical/chemical properties. A critical limitation in understanding CA might be due to the lack of high-time-resolution observations that can identify CA by both source origin and optical characteristics. Therefore, high-time-resolution measurements of total carbon (TC) and black carbon (BC) using the Carbonaceous Aerosol Speciation System (CASS) were conducted at the Chungcheong Regional Air Quality Research Center (36.77°N, 126.49°E), a suburban receptor site in Seosan, Korea. The CASS is consisted of a Total Carbon Analyzer (TCA08) and an Aethalometer (AE36s) to enable the real-time determination of TC and wavelength-dependent BC concentrations. Using TC-BC classification method, CA is systematically apportion into six distinct components, which consist of fossil fuel BC (BCff), biomass burning BC (BCbb), non-light-absorbing primary organic aerosol (POAnon-abs), light-absorbing primary organic aerosol (POABrC), non-light-absorbing secondary organic aerosol (SOAnon-abs), and light-absorbing secondary organic aerosol (SOABrC). Based on these apportionment results, we investigated the temporal variations in individual components and primary factors controlling CA variability during winter. This study offers high-time-resolution optics/chemical properties of wintertime CA in Seosan, providing a robust scientific evidence to support mitigation of regional air-quality degradation and climate change.