| Title: | Vertically Resolved Aerosol Chemistry in the Low Boundary Layer of Beijing in Summer |
| Author(s): | Li Y; Du A; Lei L; Sun J; Li Z; Zhang Z; Wang Q; Tang G; Song S; Wang Z; Wang Z; Sun Y; |
| Address: | "State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China. College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China. Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Air quality in Beijing has been improved significantly in recent years; however, our knowledge of the vertically resolved aerosol chemistry in summer remains poor. Here, we carried out comprehensive measurements of aerosol composition, gaseous species, and aerosol optical properties on a meteorological tower in Beijing in summer and compared with those measured in winter. Our results showed that aerosol liquid water (ALW) contributing approximately 50% of the total mass with higher values aloft played a crucial role in aerosol formation. Particularly, the higher nitrate concentration in city aloft than at the ground level during daytime was mainly due to the enhanced gas-particle partitioning driven by ALW and particle acidity. The vertical profiles of organic aerosol (OA) factors varied more differently in the urban boundary layer. Although the ubiquitous decreases in primary OA with the increase in height were mainly due to the influences of local emissions and vertical convection, the vertical differences in oxygenated OA between summer and winter may be related to the photochemical processing of different biogenic and anthropogenic volatile organic compounds. The single-scattering albedo, brown carbon, and absorption Angstrom exponent of aerosol particles also presented different vertical profiles between day and night due to the vertical changes in aerosol chemistry" |
| Keywords: | Aerosols/chemistry *Air Pollutants/analysis Beijing Environmental Monitoring Gases Particulate Matter/analysis Seasons *Volatile Organic Compounds aerosol composition aerosol liquid water boundary layer particle acidity vertical measurements; |
| Notes: | "MedlineLi, Yan Du, Aodong Lei, Lu Sun, Jiaxing Li, Zhijie Zhang, Zhiqiang Wang, Qingqing Tang, Guiqian Song, Shaojie Wang, Zhe Wang, Zifa Sun, Yele eng Research Support, Non-U.S. Gov't 2022/06/17 Environ Sci Technol. 2022 Jul 5; 56(13):9312-9324. doi: 10.1021/acs.est.2c02861. Epub 2022 Jun 15" |
