文章基本信息

标题：Characterization of Seasonal Difference of HULIS-CSources from Water Soluble PM2.5 in Seoul, Korea:Probing Secondary Processes
本地全文：下载
作者：Hyung-Min Lee ; Se Pyo Lee ; Yugen L 等
期刊名称：Aerosol and Air Quality Research
印刷版ISSN：1680-8584
出版年度：2021
卷号：21
期号：2
页码：1-16
DOI：10.4209/aaqr.2020.05.0233
语种：English
出版社：Chinese Association for Aerosol Research in Taiwan
摘要：HUmic-LIke Substances (HULIS) consists of a significant fraction of water-soluble organiccarbon (WSOC) and optically active brown carbon. Understanding seasonality in their abundanceand sources is an important step to quantifying their impacts on air quality and climate. In thisstudy, we characterized the seasonal variation of HULIS-C (the carbon component of HULIS) andidentified primary and secondary sources contributing to HULIS-C at an urban site in Seoul, Koreaby analyzing 131 PM2.5 samples collected over a year from October 2012 to September 2013. TheHULIS-C in Seoul had an annual average of 2.0 µg m–3, and displayed a seasonality of highestabundance in the winter (2.7 ± 1.3 µg m–3) and the lowest in the summer (1.7 ± 0.8 µg m–3). Itsfraction in WSOC reached up to 0.96 in the summer while remained relatively constant in therange of 0.4–0.6 in other seasons. Sources of HULIS-C were resolved using Positive MatrixFactorization (PMF) and checked using inter-species relationships between HILIS-C and aerosolcomponents. Specifically, secondary processes including aging and heterogeneous reaction (26%)contributes to the year-round background concentration of HULIS-C and fresh biomass burning (38%)and incomplete combustion (16%) were the major sources of underlying seasonal variation. Wealso found aging process in the secondary process had an important role in HULIS-C formationand was a dominant contributor in the summer while heterogenous reaction contributedconsiderably in other seasons. It implies that the different secondary processes in forming HULISshould be considered when the radiative forcing of brown carbon is estimated. Because theseprocesses can lead the different physicochemical properties of HULIS in aerosols.
关键词：Seasonal variation;Aging;Heterogeneous reaction;Positive matrix factorization