American Association for Aerosol Research - Abstract Submission

AAAR 38th Annual Conference
October 5 - October 9, 2020

Virtual Conference

Abstract View


Comparison of Chemical Characteristics of PM2.5 Haze Events in Beijing, China and Gwangju, Korea

JIHO JANG, Haebum Lee, Minhan Park, Nohhyeon Kwak, Ilhwa Seo, Dahye Oh, Min-Suk Bae, Kyoung-Soon Jang, Yujue Wang, Min Hu, Kihong Park, Gwangju Institute of Science and Technology

     Abstract Number: 345
     Working Group: Aerosol Chemistry

Abstract
To better understand the characteristics of PM2.5 haze events in Beijing, China, and Gwangju, Korea, simultaneous measurements of chemical composition (ions, elements, organic carbon (OC), elemental carbon (EC), and organic compounds) of fine particles were performed during the 2018-2020 winter. In this study, the PM2.5 haze event day was defined when the daily average PM2.5 mass concentration was more than the top 10% values or higher than 100 μg/m3 (Beijing, China) or 50 μg/m3 (Gwangju, Korea). During the total 82 days measurement period, 9 days of PM2.5 haze events occurred in the Beijing site and were classified into five cases. In the Gwangju site, a total of 13 days of PM2.5 haze events occurred, which could be classified into two cases. Chemical composition data suggests that PM2.5 haze events in Beijing were possibly caused by a combination of multiple primary combustion emissions (e.g. biomass burning, coal combustion, and vehicle exhaust), secondary aerosol formation under low wind speed conditions or crustal dust under high wind speed. During the PM2.5 haze events in Gwangju, the combination of secondary formation of inorganic and organic aerosols and biomass burning contributed to the fine particle which significantly increased under low wind speed conditions. During the PM2.5 haze event, K+/EC and WSOC/OC increase in Beijing site, and OC/EC and WSOC/OC increase in Gwangju site. Increase of secondary aerosol components (e.g. sulfate, nitrate, ammonium, organic acids) in fine particle was observed as a significant cause of the PM2.5 haze events in both sites, while primary combustion sources and crustal dust components contributed more to PM2.5 haze events in Beijing site than in Gwangju site.