Evidence of Rural and Suburban Sources of Urban Haze Formation in China: A Case Study From the Pearl River Delta Region

Liu, Junwen; Ding, Ping; Zong, Zheng; Li, Jun; Tian, Chongguo; Chen, Weihua; Chang, Ming; Salazar Quintero, Gary Abdiel; Shen, Chengde; Cheng, Zhineng; Chen, Yingjun; Wang, Xuemei; Szidat, Sönke; Zhang, Gan (2018). Evidence of Rural and Suburban Sources of Urban Haze Formation in China: A Case Study From the Pearl River Delta Region. Journal of Geophysical Research: Atmospheres, 123(9), pp. 4712-4726. American Geophysical Union 10.1029/2017JD027952

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Although particulate matter (PM)-driven haze is a common phenomenon in many Chinese cities, studies on the sources of its key components, such as organic carbon (OC) and elemental carbon (EC), are poorly constrained. In this study, PM with aerodynamic diameters less than 10 (PM10), 2.5 (PM2.5), and 1 μm (PM1) were collected at an urban site in the core city of the Pearl River Delta region in summer 2013. The average PM10, PM2.5, and PM1 mass concentrations were 109 ± 28.4, 57.7 ± 15.0, and 50.9 ± 13.2 μg/m3, respectively. A PM-driven haze bloom-decay process was observed from 9 to 14 July and studied based on radiocarbon (14C) and stable nitrogen isotope (15N). The 14C results revealed that 87% of EC and 53% of OC in PM2.5 were derived from fossil sources on a typical summer day (9 July), while these values fell to 79% and 40% on 12 July and 76% and 29% on 13 July, respectively, due to the invasion of nonfossil-enriched air masses from rural/suburban areas. In addition, a 15N-derived model showed that nonfossil sources contributed 5% of NH3 on 9 July, which increased to about 80% on 12 and 13 July. However, the 15N-NO3- values were relatively stable, probably because of the large area of overlap in 15N-NOx from biomass burning and traffic exhaust. To our knowledge, this work is the first study to report both daily 14C and 15N signals in China and identify nonfossil sources from rural/suburban areas as triggers of summer haze.

Item Type:

Journal Article (Original Article)


08 Faculty of Science > Department of Chemistry, Biochemistry and Pharmaceutical Sciences (DCBP)
10 Strategic Research Centers > Oeschger Centre for Climate Change Research (OCCR)

UniBE Contributor:

Salazar Quintero, Gary Abdiel, Szidat, Sönke


500 Science > 570 Life sciences; biology
500 Science > 540 Chemistry




American Geophysical Union




Sönke Szidat

Date Deposited:

24 May 2018 12:09

Last Modified:

05 Dec 2022 15:14

Publisher DOI:






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