AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Sources and Characteristics of Carbonaceous Aerosol with High-time Resolution Measurement in Beijing, China
MEI ZHENG, Caiqing Yan, Yue Liu, Xiaoying Li, Jinting Yu, Bob Cary, Anthony D.A. Hansen, Peking University
Abstract Number: 323 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract Carbonaceous aerosol plays significant role on air quality, human health and climate change. Carbonaceous aerosol in China could account for 30-50% of the total fine particulate matter mass, and is the dominant component in some high fine particulate matter (PM2.5) pollution episodes. However, compared to other regions in the world, PM2.5 in Beijing shows significant higher temporal variation. For example, its concentration can be increased by several hundred micrograms per cubic meter within 10 hours during winter period. Thus, high-time resolution measurements are required in order to better characterize carbonaceous aerosol and understand its sources. In this study, carbonaceous aerosol (including organic carbon, OC, and elemental carbon, EC) was continuously measured by Sunset Semi-Continuous OC/EC analyzer at an urban site of Beijing during winter in 2015, which is located inside the campus of Peking University. Along with continuous OC/EC measurement, aerosol light-absorption was also measured with a 7-wavelength Aethalometer (AE-33). Seasonal and diurnal variations of carbonaceous aerosol were examined, and the light absorption by organic carbon (brown carbon) and black carbon were apportioned and quantified. Our results showed that (1) carbonaceous aerosol dominated PM2.5 mass in clean days, with obvious diurnal variation, while its importance decreased in polluted days with no evident diurnal variation, (2) light-absorbing organic carbon can be clearly seen during the heating season, and it was higher than the level in non-heating season. Using the model suggested by Sandradewi et al. (2008), source apportionment of light absorbing carbonaceous aerosol is also conducted and discussed.
Corresponding author: Mei Zheng, Email: mzheng@pku.edu.cn