Characteristics of aerosol size distributions and new particle formation in the summer in Beijing


Yue DL, Hu M, Wu ZJ, Wang ZB, Guo S, Wehner B, Nowak A, Achtert P, Wiedensohler A, Jung J, et al. Characteristics of aerosol size distributions and new particle formation in the summer in Beijing. Journal of Geophysical Research-Atmospheres. 2009;114:13.


The Campaigns of Air Quality Research in Beijing and Surrounding Region 2006 (CAREBeijing-2006) were mainly focused on the influence of the regional aerosol on the air pollution in Beijing. The urban aerosol was characterized in detail. The particle size distributions were also compared to those measured at a regional site (Yufa) approximately 50 km south of the urban site at Peking University (PKU). At PKU, total particle number and volume concentrations were (1.8 +/- 0.8) x 10(4) cm(-3) and 83.5 +/- 57.9 mu m(3) cm(-3), respectively. Days in three consecutive summers of 2004, 2005, and 2006 were classified as polluted days with PM10 over 150 mu g m(-3) and nonpolluted days with lower PM10. On nonpolluted days, particle number size distributions showed a maximum at about 60 nm with Aitken mode particles dominating number concentration. On polluted days, the contribution of accumulation mode particles increased, shifting the maximum of the number size distribution to over 80 nm. On polluted days with stagnant meteorological conditions, secondary aerosol dominated, with SO42-, NO3-, and NH4+ accounting for over 60% of accumulation mode particle mass. Particle number size distributions at both sites were similar. Number and volume concentrations of total particles at Yufa were 6% and 12% lower, respectively; those of accumulation mode particles were 2% and 15% lower. This means that air pollution in Beijing is mainly a regional problem. The regional accumulation mode particles are a metric for assessing the air quality since they influence most the visibility and total mass concentration. Their number and volume concentrations on polluted days were 5 x 10(3) cm(-3) and 30 mu m(3) cm(-3), respectively. Five new particle formation (NPF) events with continuous smooth growth were observed at both PKU and Yufa during CAREBeijing-2006. These NPF events are regional or semiregional. Growth rates at PKU ranged from 1.2 to 5.6 nm h(-1), and formation rates ranged from 1.1 to 22.4 cm(-3) s(-1). SO42-, NH4+, and oxalate might be important contributors to NPF events.


ISI Document Delivery No.: 475IMTimes Cited: 81Cited Reference Count: 52Yue, Dingli Hu, Min Wu, Zhijun Wang, Zhibin Guo, Song Wehner, Birgit Nowak, Andreas Achtert, Peggy Wiedensohler, Alfred Jung, Jinsang Kim, Young J. Liu, ShawchenWehner, Birgit/C-2650-2014; Wang, Zhibin/K-7365-2013; Guo, Song/D-9218-2012; Wiedensohler, Alfred/D-1223-2013; Nowak, Andreas/B-6413-2014; Wu, Zhijun/A-7041-2012Guo, Song/0000-0002-9661-2313; Achtert, Peggy/0000-0003-0156-5276Beijing Council of Science and technology [HB200504-2]; National Key Technologies RD Program [2006BAI19B06]; National Natural Science Foundation of China [20420130348]; Deutsche Forschungsgemeinschaft (DFG) [WI 1449/9-1]This work, as part of the Campaigns of Air Quality Research in Beijing and Surrounding Region 2006 (CAREBeijing-2006), is supported by the Beijing Council of Science and technology (HB200504-2). It is also supported by the National Key Technologies R&D Program (2006BAI19B06), the National Natural Science Foundation of China (20420130348), and the Deutsche Forschungsgemeinschaft (DFG, WI 1449/9-1). The authors would like to thank Xiaoyang Liu and Jietai Mao for providing meteorological data in the summers of 2004 and 2005. We also thank Sjaak Slanina especially for revising the article.82273Amer geophysical unionWashington2169-8996