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Atmospheric Chemistry and Physics
An interactive open-access journal of the European Geosciences Union
Journal topic
- About
- Editorial board
- Articles
- Special issues
- Highlight articles
- Manuscript tracking
- Subscribe to alerts
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IF5.414
IF 5-year
5.958
5.958
CiteScore
9.7
9.7
SNIP1.517
IPP5.61
SJR2.601
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index191
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Abstracted/indexed
Volume 16, issue 14
Atmos. Chem. Phys., 16, 9109–9127, 2016
https://doi.org/10.5194/acp-16-9109-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-16-9109-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
Special issue: Pan-Eurasian Experiment (PEEX)
Atmos. Chem. Phys., 16, 9109–9127, 2016
https://doi.org/10.5194/acp-16-9109-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-16-9109-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article 25 Jul 2016
Research article | 25 Jul 2016
Highly time-resolved urban aerosol characteristics during springtime in Yangtze River Delta, China: insights from soot particle aerosol mass spectrometry
Junfeng Wang et al.
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Mutian Ma, Laura-Hélèna Rivellini, YuXi Cui, Megan D. Willis, Rio Wilkie, Jonathan P. D. Abbatt, Manjula R. Canagaratna, Junfeng Wang, Xinlei Ge, and Alex K. Y. Lee
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-303, https://doi.org/10.5194/amt-2020-303, 2020
Preprint under review for AMT
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Chemical characterization of organic coatings is important to advance our understanding of the physio-chemical properties and atmospheric processing of black carbon (BC) particles. This work develops two approaches to improve the elemental analysis of oxygenated organic coatings using a soot-particle aerosol mass spectrometer. Analyzing ambient data with the new approaches indicated that secondary organics that coated on BC were likely less oxygenated compared to those externally mixed with BC.
Junfeng Wang, Jianhuai Ye, Dantong Liu, Yangzhou Wu, Jian Zhao, Weiqi Xu, Conghui Xie, Fuzhen Shen, Jie Zhang, Paul E. Ohno, Yiming Qin, Xiuyong Zhao, Scot T. Martin, Alex K. Y. Lee, Pingqing Fu, Daniel J. Jacob, Qi Zhang, Yele Sun, Mindong Chen, and Xinlei Ge
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-750, https://doi.org/10.5194/acp-2020-750, 2020
Preprint under review for ACP
Weiqi Xu, Conghui Xie, Eleni Karnezi, Qi Zhang, Junfeng Wang, Spyros N. Pandis, Xinlei Ge, Jingwei Zhang, Junling An, Qingqing Wang, Jian Zhao, Wei Du, Yanmei Qiu, Wei Zhou, Yao He, Ying Li, Jie Li, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 19, 10205–10216, https://doi.org/10.5194/acp-19-10205-2019, https://doi.org/10.5194/acp-19-10205-2019, 2019
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We present the first aerosol volatility measurements in Beijing in summer using a thermodenuder coupled with aerosol mass spectrometers. Our results showed that organic aerosol (OA) comprised mainly semi-volatile organic compounds in summer, and the freshly oxidized secondary OA was the most volatile component. We also found quite different volatility distributions in black-carbon-containing primary and secondary OA, ambient OA, ambient secondary OA and the WRF-Chem model.
Dantong Liu, Rutambhara Joshi, Junfeng Wang, Chenjie Yu, James D. Allan, Hugh Coe, Michael J. Flynn, Conghui Xie, James Lee, Freya Squires, Simone Kotthaus, Sue Grimmond, Xinlei Ge, Yele Sun, and Pingqing Fu
Atmos. Chem. Phys., 19, 6749–6769, https://doi.org/10.5194/acp-19-6749-2019, https://doi.org/10.5194/acp-19-6749-2019, 2019
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This study provides source attribution and characterization of BC in the Beijing urban environment in both winter and summer. For the first time, the physically and chemically based source apportionments are compared to evaluate the primary source contribution and secondary processing of BC-containing particles. A method is proposed to isolate the BC from the transportation sector and coal combustion sources.
Junfeng Wang, Dantong Liu, Xinlei Ge, Yangzhou Wu, Fuzhen Shen, Mindong Chen, Jian Zhao, Conghui Xie, Qingqing Wang, Weiqi Xu, Jie Zhang, Jianlin Hu, James Allan, Rutambhara Joshi, Pingqing Fu, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 447–458, https://doi.org/10.5194/acp-19-447-2019, https://doi.org/10.5194/acp-19-447-2019, 2019
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This work is part of the UK-China APHH campaign. We used a laser-only Aerodyne soot particle aerosol mass spectrometer, for the first time, to investigate the concentrations, size distributions and chemical compositions for those ambient submicron aerosol particles only with black carbon as cores. Our findings are valuable to understand the BC properties and processes in the densely populated megacities.
Conghui Xie, Weiqi Xu, Junfeng Wang, Qingqing Wang, Dantong Liu, Guiqian Tang, Ping Chen, Wei Du, Jian Zhao, Yingjie Zhang, Wei Zhou, Tingting Han, Qingyun Bian, Jie Li, Pingqing Fu, Zifa Wang, Xinlei Ge, James Allan, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 165–179, https://doi.org/10.5194/acp-19-165-2019, https://doi.org/10.5194/acp-19-165-2019, 2019
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We present the first simultaneous real-time online measurements of aerosol optical properties at ground level and at 260 m on a meteorological tower in urban Beijing in winter. The vertical similarities and differences in scattering and absorption coefficients were characterized. The increases in MAC of BC were mainly associated with the coating materials on rBC. Coal combustion was the dominant source contribution of brown carbon followed by biomass burning and SOA in winter in Beijing.
Wei Zhou, Jian Zhao, Bin Ouyang, Archit Mehra, Weiqi Xu, Yuying Wang, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Qi Chen, Conghui Xie, Qingqing Wang, Junfeng Wang, Wei Du, Yingjie Zhang, Xinlei Ge, Penglin Ye, James D. Lee, Pingqing Fu, Zifa Wang, Douglas Worsnop, Roderic Jones, Carl J. Percival, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 18, 11581–11597, https://doi.org/10.5194/acp-18-11581-2018, https://doi.org/10.5194/acp-18-11581-2018, 2018
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We present measurements of gas-phase N2O5 and ClNO2 by ToF-CIMS during summer in urban Beijing as part of the APHH campaign. High reactivity of N2O5 indicative of active nocturnal chemistry was observed. The lifetime of N2O5 as a function of aerosol surface area and relative humidity was characterized, and N2O5 uptake coefficients were estimated. We also found that the N2O5 loss in this study is mainly attributed to its indirect loss via reactions of NO3 with VOCs and NO.
Yangzhou Wu, Xinlei Ge, Junfeng Wang, Yafei Shen, Zhaolian Ye, Shun Ge, Yun Wu, Huan Yu, and Mindong Chen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-75, https://doi.org/10.5194/acp-2018-75, 2018
Preprint withdrawn
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This work presents results regarding the secondary aerosol formations in suburan Nanjing, a site downwind of an industrial zone. We show that under such an industrialized environment, secondary species overwhelmingly dominate the fine particle mass, and moisture (relative humidity) is critical in enhancing formations of sulfate, nitrate and the most oxygenated portion of OA, while less oxygenated secondary OA was mainly driven by photochemical processing.
Wanyu Zhao, Hong Ren, Kimitaka Kawamura, Huiyun Du, Xueshun Chen, Siyao Yue, Qiaorong Xie, Lianfang Wei, Ping Li, Xin Zeng, Shaofei Kong, Yele Sun, Zifa Wang, and Pingqing Fu
Atmos. Chem. Phys., 20, 10331–10350, https://doi.org/10.5194/acp-20-10331-2020, https://doi.org/10.5194/acp-20-10331-2020, 2020
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Our observations provide detailed information on the abundance and vertical distribution of dicarboxylic acids, oxoacids and α-dicarbonyls in PM2.5 collected at three heights based on a 325 m meteorological tower in Beijing in summer. Our results demonstrate that organic acids at the ground surface are largely associated with local traffic emissions, while long-range atmospheric transport followed by photochemical ageing contributes more in the urban boundary layer than the ground surface.
Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Archit Mehra, Stephen D. Worrall, Asan Bacak, Thomas J. Bannan, Hugh Coe, Bin Ouyang, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Tuan Vu, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-785, https://doi.org/10.5194/acp-2020-785, 2020
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To understand how emission controls will impact ozone, an understanding of the sources and sinks of OH and the chemical cycling between peroxy radicals is needed. This paper presents measurements of OH, HO2, and total RO2 taken in central Beijing. The radical observations are compared to a detailed chemistry model which shows that under low NO conditions there is a missing OH source. Under high NOx conditions, the model under-predicts RO2 and impacts our ability to model ozone.
Xueshun Chen, Fangqun Yu, Wenyi Yang, Yele Sun, Huansheng Chen, Wei Du, Jian Zhao, Ying Wei, Lianfang Wei, Huiyun Du, Zhe Wang, Qizhong Wu, Jie Li, Junling An, and Zifa Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-759, https://doi.org/10.5194/acp-2020-759, 2020
Preprint under review for ACP
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The atmospheric aerosol particles have significant climate and health effects, which depend on aerosol size, composition, and mixing state. A new global-regional nested aerosol model with an advanced particle microphysics module and a volatility basis-set organic aerosol module was developed to simulate the aerosol microphysical processes. Simulations strongly suggest the important role of anthropogenic organic species in particle formation over the areas influenced by anthropogenic sources.
Mutian Ma, Laura-Hélèna Rivellini, YuXi Cui, Megan D. Willis, Rio Wilkie, Jonathan P. D. Abbatt, Manjula R. Canagaratna, Junfeng Wang, Xinlei Ge, and Alex K. Y. Lee
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-303, https://doi.org/10.5194/amt-2020-303, 2020
Preprint under review for AMT
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Chemical characterization of organic coatings is important to advance our understanding of the physio-chemical properties and atmospheric processing of black carbon (BC) particles. This work develops two approaches to improve the elemental analysis of oxygenated organic coatings using a soot-particle aerosol mass spectrometer. Analyzing ambient data with the new approaches indicated that secondary organics that coated on BC were likely less oxygenated compared to those externally mixed with BC.
Yibei Wan, Xiangpeng Huang, Bin Jiang, Binyu Kuang, Manfei Lin, Deming Xia, Yuhong Liao, Jingwen Chen, Jian Zhen Yu, and Huan Yu
Atmos. Chem. Phys., 20, 9821–9835, https://doi.org/10.5194/acp-20-9821-2020, https://doi.org/10.5194/acp-20-9821-2020, 2020
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Biogenic iodine emission from macroalgae and microalgae could initiate atmospheric new particle formation (NPF). But it is unknown if other species are needed to drive the growth of new iodine particles in the marine boundary layer. Unlike the deeper understanding of organic compounds driving continental NPF, little is known about the organics involved in coastal or open-ocean NPF. This article reveals a new group of important organic compounds involved in this process.
Junfeng Wang, Jianhuai Ye, Dantong Liu, Yangzhou Wu, Jian Zhao, Weiqi Xu, Conghui Xie, Fuzhen Shen, Jie Zhang, Paul E. Ohno, Yiming Qin, Xiuyong Zhao, Scot T. Martin, Alex K. Y. Lee, Pingqing Fu, Daniel J. Jacob, Qi Zhang, Yele Sun, Mindong Chen, and Xinlei Ge
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-750, https://doi.org/10.5194/acp-2020-750, 2020
Preprint under review for ACP
Lu Qi, Alexander L. Vogel, Sepideh Esmaeilirad, Liming Cao, Jing Zheng, Jean-Luc Jaffrezo, Paola Fermo, Anne Kasper-Giebl, Kaspar R. Daellenbach, Mindong Chen, Xinlei Ge, Urs Baltensperger, André S. H. Prévôt, and Jay G. Slowik
Atmos. Chem. Phys., 20, 7875–7893, https://doi.org/10.5194/acp-20-7875-2020, https://doi.org/10.5194/acp-20-7875-2020, 2020
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We present the first application of this online and offline strategy using the new extractive electrospray ionization time-of-flight mass spectrometer (EESI-TOF), which achieves increased chemical specificity relative to other online techniques. Measurement and source apportionment of 1 year of filter samples collected in Zurich, Switzerland, show seasonal contributions from fresh and aged wood combustion in winter and biogenic emission-derived SOA in summer, as well as other sources.
Junchen Guo, Shengzhen Zhou, Mingfu Cai, Jun Zhao, Wei Song, Weixiong Zhao, Weiwei Hu, Yele Sun, Yao He, Chengqiang Yang, Xuezhe Xu, Zhisheng Zhang, Peng Cheng, Qi Fan, Jian Hang, Shaojia Fan, Xinming Wang, and Xuemei Wang
Atmos. Chem. Phys., 20, 7595–7615, https://doi.org/10.5194/acp-20-7595-2020, https://doi.org/10.5194/acp-20-7595-2020, 2020
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We characterized non-refractory submicron particulate matter (PM1.0) during winter in Guangzhou, south China. Chemical composition and key sources of ambient PM1.0 are revealed, highlighting the significant role of SOA. The relationship with SOA and peroxy radicals indicated gas-phase oxidation contributed predominantly to SOA formation during non-pollution periods, while heterogeneous/multiphase reactions played more important roles in SOA formation during pollution periods.
Jingyi Li, Haowen Zhang, Qi Ying, Zhijun Wu, Yanli Zhang, Xinming Wang, Xinghua Li, Yele Sun, Min Hu, Yuanhang Zhang, and Jianlin Hu
Atmos. Chem. Phys., 20, 7291–7306, https://doi.org/10.5194/acp-20-7291-2020, https://doi.org/10.5194/acp-20-7291-2020, 2020
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Large gaps still exist in modeled and observed secondary organic aerosol (SOA) mass loading and properties. Here we investigated the impacts of water partitioning into organic aerosol and nonideality of the organic–water mixture on SOA over eastern China using a regional 3D model. SOA is increased more significantly in humid and hot environments. Increases in SOA further cause an enhancement of the cooling effects of aerosols. It is crucial to consider the above processes in modeling SOA.
Weiqi Xu, Yao He, Yanmei Qiu, Chun Chen, Conghui Xie, Lu Lei, Zhijie Li, Jiaxing Sun, Junyao Li, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Meas. Tech., 13, 3205–3219, https://doi.org/10.5194/amt-13-3205-2020, https://doi.org/10.5194/amt-13-3205-2020, 2020
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We characterized mass spectral features of organic aerosol (OA) and water-soluble OA (WSOA) from 21 cooking, crop straw, wood, and coal burning experiments using aerosol mass spectrometers with standard and capture vaporizers, and we demonstrated the applications of source spectral profiles in improving source apportionment of ambient OA at a highly polluted rural site in the North China Plain in winter.
Hwajin Kim, Qi Zhang, and Yele Sun
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-382, https://doi.org/10.5194/acp-2020-382, 2020
Revised manuscript accepted for ACP
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Severe spring haze and influences of long-range transport in the Seoul metropolitan area in March 2019 was investigated. Simultaneous downwind (SMA) and upwind (Beijing) measurements using AMS and ACSM over the same period showed that the PM species can be transported approximately in two days. Nitrate was the most responsible and sulfate and two regional transport influenced SOAs also contributed. Enhancement of Pb also showed that the haze in SMA was influenced by the regional transport.
Jing Yang, Wanyu Zhao, Lianfang Wei, Qiang Zhang, Yue Zhao, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Xiaole Pan, Yele Sun, Zifa Wang, Cong-Qiang Liu, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 20, 6841–6860, https://doi.org/10.5194/acp-20-6841-2020, https://doi.org/10.5194/acp-20-6841-2020, 2020
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Our observations provide novel detailed information on the atmospheric abundances and spatial distributions of dicarboxylic acids, oxoacids, and α-dicarbonyls in marine aerosols collected from the South China Sea to the East Indian Ocean. Our results demonstrate that the continental outflow of both biogenic and anthropogenic precursors followed by photochemical aging is one of the main sources and formation processes of marine organic aerosols over the tropical oceanic regions.
Qiaorong Xie, Sihui Su, Shuang Chen, Yisheng Xu, Dong Cao, Jing Chen, Lujie Ren, Siyao Yue, Wanyu Zhao, Yele Sun, Zifa Wang, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, Guibin Jiang, Cong-Qiang Liu, and Pingqing Fu
Atmos. Chem. Phys., 20, 6803–6820, https://doi.org/10.5194/acp-20-6803-2020, https://doi.org/10.5194/acp-20-6803-2020, 2020
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Current knowledge on firework-related organic aerosols is very limited. Here the detailed molecular composition of organics in urban aerosols was characterized using ultrahigh-resolution FT-ICR mass spectrometry. Our findings highlight that firework emission leads to a sharp increase in CHO, CHNO, and CHOS containing high-molecular-weight species, particularly aromatic-like substances, which affect the physicochemical properties such as the light absorption and health effects of urban aerosols.
Shengzhen Zhou, Luolin Wu, Junchen Guo, Weihua Chen, Xuemei Wang, Jun Zhao, Yafang Cheng, Zuzhao Huang, Jinpu Zhang, Yele Sun, Pingqing Fu, Shiguo Jia, Jun Tao, Yanning Chen, and Junxia Kuang
Atmos. Chem. Phys., 20, 6435–6453, https://doi.org/10.5194/acp-20-6435-2020, https://doi.org/10.5194/acp-20-6435-2020, 2020
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In this work, measurements of size-segregated aerosols were conducted at three altitudes (ground level, 118 m, and 488 m) on the 610 m high Canton Tower in southern China. Vertical variations of PM and size-segregated chemical compositions were investigated. The results indicated that meteorological parameters and atmospheric aqueous and heterogeneous reactions together led to aerosol formation and haze episodes in the Pearl River Delta region during the measurement periods.
Hang Liu, Xiaole Pan, Dantong Liu, Xiaoyong Liu, Xueshun Chen, Yu Tian, Yele Sun, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 20, 5771–5785, https://doi.org/10.5194/acp-20-5771-2020, https://doi.org/10.5194/acp-20-5771-2020, 2020
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The bare black carbon (BC) was in a fractal structure. With coating thickness increasing, BC changed from a fractal structure to a core–shell structure. In the ambient atmosphere, plenty of BC particles were not in a perfect core–shell structure. This study brought attention to the combined effects of morphology and coating thickness on the absorption enhancement of BC-containing particles, which is helpful for determining the climatic effects of BC.
Jing Cai, Biwu Chu, Lei Yao, Chao Yan, Liine M. Heikkinen, Feixue Zheng, Chang Li, Xiaolong Fan, Shaojun Zhang, Daoyuan Yang, Yonghong Wang, Tom V. Kokkonen, Tommy Chan, Ying Zhou, Lubna Dada, Yongchun Liu, Hong He, Pauli Paasonen, Joni T. Kujansuu, Tuukka Petäjä, Claudia Mohr, Juha Kangasluoma, Federico Bianchi, Yele Sun, Philip L. Croteau, Douglas R. Worsnop, Veli-Matti Kerminen, Wei Du, Markku Kulmala, and Kaspar R. Daellenbach
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-248, https://doi.org/10.5194/acp-2020-248, 2020
Revised manuscript accepted for ACP
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By applying both OA-PMF and Size-PMF at the same urban measurement site in Beijing, similar particle source-types, including vehicular emissions, cooking emissions and secondary formation-related sources were resolved by both frameworks and agreed well. It is also found that in the absence of new-particle formation, vehicular and cooking emissions dominate the particle number concentration while secondary particulate matter governed PM2.5 mass during spring and summer in Beijing.
Eloise J. Slater, Lisa K. Whalley, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freja Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Leigh R. Crilley, Louisa Kramer, William Bloss, Tuan Vu, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-362, https://doi.org/10.5194/acp-2020-362, 2020
Revised manuscript accepted for ACP
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The paper details atmospheric chemistry in a mega-city (Beijing), focussing on radicals which mediate the formation of secondary pollutants such as ozone and particles. Highly polluted conditions were experienced, including the highest ever levels of nitric oxide (NO) with simultaneous radical measurements. Radical concentrations were large during “haze” events, demonstrating active photochemistry was occurring. Modelling showed that our understanding of the chemistry at high NOx is incomplete.
Ruqian Miao, Qi Chen, Yan Zheng, Xi Cheng, Yele Sun, Paul I. Palmer, Manish Shrivastava, Jianping Guo, Qiang Zhang, Yuhan Liu, Zhaofeng Tan, Xuefei Ma, Shiyi Chen, Limin Zeng, Keding Lu, and Yuanhang Zhang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-76, https://doi.org/10.5194/acp-2020-76, 2020
Revised manuscript accepted for ACP
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In this study we evaluated the model performances for simulating SIA and OA in PM2.5 in China against comprehensive data sets. The potential biases from factors related to meteorology, emission, chemistry, and atmospheric removal are systematically investigated. This study provides a comprehensive understanding about modeling PM2.5, which is important for studies on the effectiveness of the emission control strategies. It also provides recommendations for future model development.
Jingsha Xu, Shaojie Song, Roy M. Harrison, Congbo Song, Lianfang Wei, Qiang Zhang, Yele Sun, Lu Lei, Chao Zhang, Xiaohong Yao, Dihui Chen, Weijun Li, Miaomiao Wu, Hezhong Tian, Lining Luo, Shengrui Tong, Weiran Li, Junling Wang, Guoliang Shi, Yanqi Huangfu, Yingze Tian, Baozhu Ge, Shaoli Su, Chao Peng, Yang Chen, Fumo Yang, Aleksandra Mihajlidi-Zelić, Dragana Đorđević, Stefan J. Swift, Imogen Andrews, Jacqueline F. Hamilton, Ye Sun, Agung Kramawijaya, Jinxiu Han, Supattarachai Saksakulkrai, Clarissa Baldo, Siqi Hou, Feixue Zheng, Kaspar R. Daellenbach, Chao Yan, Yongchun Liu, Markku Kulmala, Pingqing Fu, and Zongbo Shi
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-156, https://doi.org/10.5194/amt-2020-156, 2020
Revised manuscript accepted for AMT
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An inter-laboratory comparison exercise was conducted for the first time to examine the difference of water-soluble inorganic ions (WSII) measured by 10 labs using Ion Chromatography and by 2 online Aerosol Chemical Speciation Monitor method. Major ions including SO42−, NO3−, NH4+ agreed well in 10 IC labs, and correlated well with ACSM. WSII inter-lab variability strongly affected aerosol acidity results based on ion balance, but aerosol pH computed by ISORROPIA-II were very similar.
Liya Ma, Yujiao Zhu, Mei Zheng, Yele Sun, Lei Huang, Xiaohuan Liu, Yang Gao, Yanjie Shen, Huiwang Gao, and Xiaohong Yao
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-1151, https://doi.org/10.5194/acp-2019-1151, 2020
Revised manuscript under review for ACP
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In this study, we investigate three patterns of new particles growing to CCN size, i.e., one-stage growth, two-stage growth-A and growth-B. Combining the observations of gaseous pollutants and the measured (or modeled) particulate chemical species, the three growth patterns were discussed in terms of the spatial heterogeneity, the formation of secondary aerosols and the evaporation of semi-volatile particulates. The survival probability of new particles to CCN size was also discussed.
Fanhao Meng, Min Qin, Ke Tang, Jun Duan, Wu Fang, Shuaixi Liang, Kaidi Ye, Pinhua Xie, Yele Sun, Conghui Xie, Chunxiang Ye, Pingqing Fu, Jianguo Liu, and Wenqing Liu
Atmos. Chem. Phys., 20, 5071–5092, https://doi.org/10.5194/acp-20-5071-2020, https://doi.org/10.5194/acp-20-5071-2020, 2020
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Nitrous acid (HONO), a major precursor of the OH radical, plays a key role in atmospheric chemistry, but its sources are still debated. The first high-resolution vertical measurements of HONO and NO2 were conducted in Beijing to investigate the nocturnal sources of HONO at different stages of pollution. The ground surface dominated HONO production by heterogeneous conversion of NO2 during clean episodes, but the aerosol production was an important nighttime HONO source during haze episodes.
Jianjun Li, Qi Zhang, Gehui Wang, Jin Li, Can Wu, Lang Liu, Jiayuan Wang, Wenqing Jiang, Lijuan Li, Kin Fai Ho, and Junji Cao
Atmos. Chem. Phys., 20, 4889–4904, https://doi.org/10.5194/acp-20-4889-2020, https://doi.org/10.5194/acp-20-4889-2020, 2020
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We examined light absorption properties and molecular composition of water-soluble (WS) and water-insoluble (WI) BrC in PM2.5 collected from northwest China. We found that photochemical formation contributes significantly to light absorption of WI-BrC in summer, whereas aqueous-phase reactions play an important role in secondary WS-BrC formation in winter. BrC was estimated to account for 1.36 % and 3.74 %, respectively, of total down-welling solar radiation in the UV range in summer and winter.
Lawrence I. Kleinman, Arthur J. Sedlacek III, Kouji Adachi, Peter R. Buseck, Sonya Collier, Manvendra K. Dubey, Anna L. Hodshire, Ernie Lewis, Timothy B. Onasch, Jeffery R. Pierce, John Shilling, Stephen R. Springston, Jian Wang, Qi Zhang, Shan Zhou, and Robert J. Yokelson
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-239, https://doi.org/10.5194/acp-2020-239, 2020
Revised manuscript accepted for ACP
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Aerosols from wildfires effect the Earth's temperature by absorbing light or reflecting it back into space. This study investigates time-dependent chemical, microphysical, and optical properties of aerosols generated by wildfires in the Pacific Northwest, USA. Wildfire smoke plumes were traversed by an instrumented aircraft at locations near the fire and up to 3.5-hour travel time downwind. Although there was no net aerosol production, aerosol particles grew and became more efficient scatters.
Chaomin Wang, Caihong Wu, Sihang Wang, Jipeng Qi, Baolin Wang, Zelong Wang, Weiwei Hu, Wei Chen, Chenshuo Ye, Wenjie Wang, Yele Sun, Chen Wang, Shan Huang, Wei Song, Xinming Wang, Suxia Yang, Shenyang Zhang, Wanyun Xu, Nan Ma, Zhanyi Zhang, Bin Jiang, Hang Su, Yafang Cheng, Xuemei Wang, Min Shao, and Bin Yuan
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-145, https://doi.org/10.5194/acp-2020-145, 2020
Revised manuscript under review for ACP
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We utilized a novel online mass spectrometry method to measure the total concentration of higher alkanes at each carbon number at two different sites in China, allowing to take into account SOA contributions from all isomers for higher alkanes. We found that higher alkanes account for significant fractions of SOA formation at the two sites. The contributions are comparable or even higher than single-ring aromatics, the mostly recognized SOA precursors in urban air.
Chenjie Yu, Dantong Liu, Kurtis Broda, Rutambhara Joshi, Jason Olfert, Yele Sun, Pingqing Fu, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 20, 3645–3661, https://doi.org/10.5194/acp-20-3645-2020, https://doi.org/10.5194/acp-20-3645-2020, 2020
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This study presents the first atmospheric application of a new morphology-independent measurement for the quantification of the mixing state of rBC-containing particles in urban Beijing as part of the UK–China APHH campaign. An inversion method has been applied for better quantification of rBC mixing state. The mass-resolved rBC mixing state information presented here has implications for detailed models of BC, its optical properties and its atmospheric life cycle.
Shaofeng Xu, Lujie Ren, Yunchao Lang, Shengjie Hou, Hong Ren, Lianfang Wei, Libin Wu, Junjun Deng, Wei Hu, Xiaole Pan, Yele Sun, Zifa Wang, Hang Su, Yafang Cheng, and Pingqing Fu
Atmos. Chem. Phys., 20, 3623–3644, https://doi.org/10.5194/acp-20-3623-2020, https://doi.org/10.5194/acp-20-3623-2020, 2020
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Current knowledge on the size distribution of biogenic primary organic aerosols in urban regions with heavy haze pollution is very limited. Here we performed a year-round study focusing on the organic molecular composition of size-segregated aerosol samples collected in urban Beijing during haze and non-haze days to elucidate the seasonal contributions of biomass burning, fungal spores, and plant debris to organic carbon as well as the influences from local emissions and long-range transport.
Leigh R. Crilley, Ajit Singh, Louisa J. Kramer, Marvin D. Shaw, Mohammed S. Alam, Joshua S. Apte, William J. Bloss, Lea Hildebrandt Ruiz, Pingqing Fu, Weiqi Fu, Shahzad Gani, Michael Gatari, Evgenia Ilyinskaya, Alastair C. Lewis, David Ng'ang'a, Yele Sun, Rachel C. W. Whitty, Siyao Yue, Stuart Young, and Francis D. Pope
Atmos. Meas. Tech., 13, 1181–1193, https://doi.org/10.5194/amt-13-1181-2020, https://doi.org/10.5194/amt-13-1181-2020, 2020
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There is considerable interest in using low-cost optical particle counters (OPCs) for particle mass measurements; however, there is no agreed upon method with respect to calibration. Here we exploit a number of datasets globally to demonstrate that particle composition and relative humidity are the key factors affecting measured concentrations from a low-cost OPC, and we present a simple correction methodology that corrects for this influence.
Lu Lei, Conghui Xie, Dawei Wang, Yao He, Qingqing Wang, Wei Zhou, Wei Hu, Pingqing Fu, Yong Chen, Xiaole Pan, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 20, 2877–2890, https://doi.org/10.5194/acp-20-2877-2020, https://doi.org/10.5194/acp-20-2877-2020, 2020
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We characterized aerosol composition and sources near two steel plants in a coastal region in fall and spring seasons. Our results showed substantially different aerosol composition and sources between the two seasons. We observed significant impacts of steel plant emissions on aerosol chemistry nearby, and we found that aerosol particles emitted from the steel plants were dominated by ammonium sulfate/bisulfate; NOx/CO and NOx/SO2 were distinct from those in the absence of industrial plumes.
Xinxin Fan, Jieyao Liu, Fang Zhang, Lu Chen, Don Collins, Weiqi Xu, Xiaoai Jin, Jingye Ren, Yuying Wang, Hao Wu, Shangze Li, Yele Sun, and Zhanqing Li
Atmos. Chem. Phys., 20, 915–929, https://doi.org/10.5194/acp-20-915-2020, https://doi.org/10.5194/acp-20-915-2020, 2020
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Aerosol effects on visibility and climate are influenced by their hygroscopicity. By contrasting data from two techniques between summer and winter in Beijing, we investigate the effect of aerosol aging, mixing state, and local sources on its hygroscopicity. We revealed that inappropriate use of the density of BC and organics results in large uncertainty in calculating aerosols hygroscopicity. Our results are helpful for parameterization in models.
Xiaoai Jin, Yuying Wang, Zhanqing Li, Fang Zhang, Weiqi Xu, Yele Sun, Xinxin Fan, Guangyu Chen, Hao Wu, Jingye Ren, Qiuyan Wang, and Maureen Cribb
Atmos. Chem. Phys., 20, 901–914, https://doi.org/10.5194/acp-20-901-2020, https://doi.org/10.5194/acp-20-901-2020, 2020
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In this study the aerosol liquid water content (ALWC) is determined from aerosol hygroscopic growth factor (GF) measurement (ALWCHTDMA) and also simulated by the ISORROPIA II thermodynamic model (ALWCISO). We found that ALWC contributed by organics (ALWCOrg) accounts for 30 % ± 22 % of the total ALWC in winter in Beijing. A case study reveals that ALWCOrg plays an important role in the formation of secondary aerosols through multiphase reactions at the initial stage of a heavy-haze episode.
Ye Kuang, Yao He, Wanyun Xu, Pusheng Zhao, Yafang Cheng, Gang Zhao, Jiangchuan Tao, Nan Ma, Hang Su, Yanyan Zhang, Jiayin Sun, Peng Cheng, Wenda Yang, Shaobin Zhang, Cheng Wu, Yele Sun, and Chunsheng Zhao
Atmos. Chem. Phys., 20, 865–880, https://doi.org/10.5194/acp-20-865-2020, https://doi.org/10.5194/acp-20-865-2020, 2020
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A new method was developed to calculate hygroscopicity parameter κ of organic aerosols (κOA) based on aerosol light-scattering measurements and bulk aerosol chemical-composition measurements. Derived high-time-resolution κOA varied in a wide range (near 0 to 0.25), and the organic aerosol oxidation degree significantly impacts variations in κOA. Distinct diurnal variation in κOA is found, and its relationship with oxygenated organic aerosol is discussed.
Yanbing Fan, Cong-Qiang Liu, Linjie Li, Lujie Ren, Hong Ren, Zhimin Zhang, Qinkai Li, Shuang Wang, Wei Hu, Junjun Deng, Libin Wu, Shujun Zhong, Yue Zhao, Chandra Mouli Pavuluri, Xiaodong Li, Xiaole Pan, Yele Sun, Zifa Wang, Kimitaka Kawamura, Zongbo Shi, and Pingqing Fu
Atmos. Chem. Phys., 20, 117–137, https://doi.org/10.5194/acp-20-117-2020, https://doi.org/10.5194/acp-20-117-2020, 2020
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This study provides useful knowledge on the abundance, sources, and formation processes of organic aerosols in the coastal megacity of Tianjin, North China, based on the investigation of the molecular composition, diurnal variation, and winter/summer differences under the influence of land/sea breezes and the Asian summer monsoon.
Danhui Xu, Baozhu Ge, Xueshun Chen, Yele Sun, Nianliang Cheng, Mei Li, Xiaole Pan, Zhiqiang Ma, Yuepeng Pan, and Zifa Wang
Atmos. Chem. Phys., 19, 15569–15581, https://doi.org/10.5194/acp-19-15569-2019, https://doi.org/10.5194/acp-19-15569-2019, 2019
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Wet deposition is one of the most important and efficient removal mechanisms in the evolution of the air pollution. Due to the lack of a localized parameterization scheme and some mechanisms being neglected in theoretical estimations and modeling calculations, below-cloud wet scavenging coefficients (BWSC) have large uncertainties. We compare the BWSCs under the same conditions to perform a multi-method evaluation in order to describe their characteristics.
Hang Liu, Xiaole Pan, Yu Wu, Dawei Wang, Yu Tian, Xiaoyong Liu, Lu Lei, Yele Sun, Pingqing Fu, and Zifa Wang
Atmos. Chem. Phys., 19, 14791–14804, https://doi.org/10.5194/acp-19-14791-2019, https://doi.org/10.5194/acp-19-14791-2019, 2019
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The relationship among the effective density, rBC's coating thickness, and rBC's morphology was investigated. rBC with larger effective density adopted a more regular shape due to more coating thickness. The effective density distribution of ambient rBC was also measured. From the information of effective density, the ambient rBC mainly adopts an irregular shape, which can cause large uncertainties in the rBC's optical properties.
Jianjun Li, Gehui Wang, Qi Zhang, Jin Li, Can Wu, Wenqing Jiang, Tong Zhu, and Limin Zeng
Atmos. Chem. Phys., 19, 10481–10496, https://doi.org/10.5194/acp-19-10481-2019, https://doi.org/10.5194/acp-19-10481-2019, 2019
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In this study, we investigated molecular compositions of organic aerosols (OAs) in summertime PM2.5 at a rural site in the North China Plain. We found that regional emission from field biomass burning (BB) significantly affects the concentration and molecular distribution of aliphatic lipids, sugars, and terpene-derived SOA, but has limited influence on PAHs, hopenes, and phthalates. The contribution of BB to OA increased by more than 50 % during the period influenced by regional open-field BB.
Weiqi Xu, Conghui Xie, Eleni Karnezi, Qi Zhang, Junfeng Wang, Spyros N. Pandis, Xinlei Ge, Jingwei Zhang, Junling An, Qingqing Wang, Jian Zhao, Wei Du, Yanmei Qiu, Wei Zhou, Yao He, Ying Li, Jie Li, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 19, 10205–10216, https://doi.org/10.5194/acp-19-10205-2019, https://doi.org/10.5194/acp-19-10205-2019, 2019
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We present the first aerosol volatility measurements in Beijing in summer using a thermodenuder coupled with aerosol mass spectrometers. Our results showed that organic aerosol (OA) comprised mainly semi-volatile organic compounds in summer, and the freshly oxidized secondary OA was the most volatile component. We also found quite different volatility distributions in black-carbon-containing primary and secondary OA, ambient OA, ambient secondary OA and the WRF-Chem model.
Michael Hollaway, Oliver Wild, Ting Yang, Yele Sun, Weiqi Xu, Conghui Xie, Lisa Whalley, Eloise Slater, Dwayne Heard, and Dantong Liu
Atmos. Chem. Phys., 19, 9699–9714, https://doi.org/10.5194/acp-19-9699-2019, https://doi.org/10.5194/acp-19-9699-2019, 2019
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This study, for the first time, uses combinations of aerosol and lidar data to drive an offline photolysis scheme. Absorbing species are shown to have the greatest impact on photolysis rate constants in the winter and scattering aerosol are shown to dominate responses in the summer. During haze episodes, aerosols are shown to produce a greater impact than cloud cover. The findings demonstrate the potential photochemical impacts of haze pollution in a highly polluted urban environment.
Huiyun Du, Jie Li, Xueshun Chen, Zifa Wang, Yele Sun, Pingqing Fu, Jianjun Li, Jian Gao, and Ying Wei
Atmos. Chem. Phys., 19, 9351–9370, https://doi.org/10.5194/acp-19-9351-2019, https://doi.org/10.5194/acp-19-9351-2019, 2019
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Regional transport and heterogeneous reactions play crucial roles in haze formation. Using a chemical transport model, we found that chemical transformation of SO2 along the transport pathway from source regions to Beijing was the major source of sulfate. Heterogeneous chemistry had a stronger effect under high humidity and high pollution levels. Aerosols underwent aging during transport which altered the aerosol size and the degree of aging.
Tabish Umar Ansari, Oliver Wild, Jie Li, Ting Yang, Weiqi Xu, Yele Sun, and Zifa Wang
Atmos. Chem. Phys., 19, 8651–8668, https://doi.org/10.5194/acp-19-8651-2019, https://doi.org/10.5194/acp-19-8651-2019, 2019
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We explore the effectiveness of short-term emission controls on haze events in Beijing in October–November 2014 with high-resolution model studies. The model captures observed hourly variation in key pollutants well, but representation of boundary layer processes remains a key constraint. The controls contributed to improved air quality in early November but would not have been sufficient had the meteorology been less favourable. We quantify the much more stringent controls needed in that case.
Xiaole Pan, Hang Liu, Yu Wu, Yu Tian, Yele Sun, Conghui Xie, Xiaoyong Liu, Tianhai Cheng, and Zifa Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-433, https://doi.org/10.5194/acp-2019-433, 2019
Revised manuscript not accepted
Ying Wei, Xueshun Chen, Huansheng Chen, Jie Li, Zifa Wang, Wenyi Yang, Baozhu Ge, Huiyun Du, Jianqi Hao, Wei Wang, Jianjun Li, Yele Sun, and Huili Huang
Atmos. Chem. Phys., 19, 8269–8296, https://doi.org/10.5194/acp-19-8269-2019, https://doi.org/10.5194/acp-19-8269-2019, 2019
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This study presents a full description and evaluation of a global–regional nested aerosol and atmospheric chemistry model (IAP-AACM). The simulation for 2014 is evaluated against model datasets and a range of observational datasets. The results show that IAP-AACM is within the range of other models, and reproduces both spatial and seasonal variation of trace gases and aerosols over most areas well. In future, we recommend improving the model's ability to capture high spatial variation of PM2.5.
Lu Qi, Mindong Chen, Giulia Stefenelli, Veronika Pospisilova, Yandong Tong, Amelie Bertrand, Christoph Hueglin, Xinlei Ge, Urs Baltensperger, André S. H. Prévôt, and Jay G. Slowik
Atmos. Chem. Phys., 19, 8037–8062, https://doi.org/10.5194/acp-19-8037-2019, https://doi.org/10.5194/acp-19-8037-2019, 2019
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Current understanding of OA sources is limited by the chemical resolution of existing real-time measurement technology. We describe the first wintertime deployment of a novel extractive electrospray ionization time-of-flight mass spectrometer, which provides near-molecular OA measurements with high time resolution. We show that biomass combustion strongly influences winter OA. Via factor analysis, aging-dependent signatures and time contributions of biomass-combustion-derived OA are resolved.
Xinghua Zhang, Jianzhong Xu, Shichang Kang, Qi Zhang, and Junying Sun
Atmos. Chem. Phys., 19, 7897–7911, https://doi.org/10.5194/acp-19-7897-2019, https://doi.org/10.5194/acp-19-7897-2019, 2019
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Highly time resolved chemistry and sources of PM1 were measured by an Aerodyne HR-ToF-AMS at Waliguan Baseline Observatory, a high-altitude background station at the northeastern edge of Qinghai–Tibet Plateau (QTP), during summer 2017. Relatively higher mass concentration of PM1 and dominant sulfate contribution were observed in this site compared to those at other high-elevation sites in the southern or central QTP, indicating the different aerosol sources between them.
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546, https://doi.org/10.5194/acp-19-7519-2019, https://doi.org/10.5194/acp-19-7519-2019, 2019
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APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
Linlin Wang, Junkai Liu, Zhiqiu Gao, Yubin Li, Meng Huang, Sihui Fan, Xiaoye Zhang, Yuanjian Yang, Shiguang Miao, Han Zou, Yele Sun, Yong Chen, and Ting Yang
Atmos. Chem. Phys., 19, 6949–6967, https://doi.org/10.5194/acp-19-6949-2019, https://doi.org/10.5194/acp-19-6949-2019, 2019
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Urban boundary layer (UBL) affects the physical and chemical processes of the pollutants, and UBL structure can also be altered by pollutants. This paper presents the interactions between air pollution and the UBL structure by using the field data mainly collected from a 325 m meteorology tower, as well as from a Doppler wind lidar, during a severe heavy pollution event that occurred during 1–4 December 2016 in Beijing.
Dantong Liu, Rutambhara Joshi, Junfeng Wang, Chenjie Yu, James D. Allan, Hugh Coe, Michael J. Flynn, Conghui Xie, James Lee, Freya Squires, Simone Kotthaus, Sue Grimmond, Xinlei Ge, Yele Sun, and Pingqing Fu
Atmos. Chem. Phys., 19, 6749–6769, https://doi.org/10.5194/acp-19-6749-2019, https://doi.org/10.5194/acp-19-6749-2019, 2019
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This study provides source attribution and characterization of BC in the Beijing urban environment in both winter and summer. For the first time, the physically and chemically based source apportionments are compared to evaluate the primary source contribution and secondary processing of BC-containing particles. A method is proposed to isolate the BC from the transportation sector and coal combustion sources.
Xionghui Qiu, Qi Ying, Shuxiao Wang, Lei Duan, Jian Zhao, Jia Xing, Dian Ding, Yele Sun, Baoxian Liu, Aijun Shi, Xiao Yan, Qingcheng Xu, and Jiming Hao
Atmos. Chem. Phys., 19, 6737–6747, https://doi.org/10.5194/acp-19-6737-2019, https://doi.org/10.5194/acp-19-6737-2019, 2019
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Current chemical transport models cannot capture the diurnal and nocturnal variation in atmospheric nitrate, which may be relative to the missing atmospheric chlorine chemistry. In this work, the Community Multiscale Air Quality (CMAQ) model with improved chlorine heterogeneous chemistry is applied to simulate the impact of chlorine chemistry on summer nitrate concentrations in Beijing. The results of this work can improve our understanding of nitrate formation.
Richie Kaur, Jacqueline R. Labins, Scarlett S. Helbock, Wenqing Jiang, Keith J. Bein, Qi Zhang, and Cort Anastasio
Atmos. Chem. Phys., 19, 6579–6594, https://doi.org/10.5194/acp-19-6579-2019, https://doi.org/10.5194/acp-19-6579-2019, 2019
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We measured hydroxyl radical (•OH), singlet oxygen (1O2*), and organic triplets (3C*) in illuminated aqueous particle extracts. After measuring the impact of dilution on oxidant concentrations, we extrapolated our results to predict them in ambient particles – 1O2* and 3C* concentrations appear to be greatly enhanced, while •OH appears largely unchanged. Two of these oxidants (1O2*, 3C*) are not yet included in atmospheric models, and our results make it possible to include them in the future.
Jialin Li, Meigen Zhang, Guiqian Tang, Yele Sun, Fangkun Wu, and Yongfu Xu
Atmos. Chem. Phys., 19, 6481–6495, https://doi.org/10.5194/acp-19-6481-2019, https://doi.org/10.5194/acp-19-6481-2019, 2019
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There are large uncertainties in the sources of secondary organic aerosol (SOA). Simulations of SOA concentrations in China with aqueous SOA formation pathway updated and glyoxal simulation improved reveal that dicarbonyl-derived SOA (AAQ) can explain a significant fraction of the unaccounted SOA sources. The mean AAQ can contribute 60.6 % and 64.5 % to the total concentration of SOA in summer and fall, respectively.
Jingyuan Shao, Qianjie Chen, Yuxuan Wang, Xiao Lu, Pengzhen He, Yele Sun, Viral Shah, Randall V. Martin, Sajeev Philip, Shaojie Song, Yue Zhao, Zhouqing Xie, Lin Zhang, and Becky Alexander
Atmos. Chem. Phys., 19, 6107–6123, https://doi.org/10.5194/acp-19-6107-2019, https://doi.org/10.5194/acp-19-6107-2019, 2019
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Sulfate is a key species contributing to particle formation and growth during wintertime Chinese haze events. This study combines observations and modeling of oxygen isotope signatures in sulfate aerosol to investigate its formation mechanisms, with a focus on heterogeneous production on aerosol surface via H2O2, O3, and NO2 and trace metal catalyzed oxidation. Contributions from different formation pathways are presented.
Zhenying Xu, Mingxu Liu, Minsi Zhang, Yu Song, Shuxiao Wang, Lin Zhang, Tingting Xu, Tiantian Wang, Caiqing Yan, Tian Zhou, Yele Sun, Yuepeng Pan, Min Hu, Mei Zheng, and Tong Zhu
Atmos. Chem. Phys., 19, 5605–5613, https://doi.org/10.5194/acp-19-5605-2019, https://doi.org/10.5194/acp-19-5605-2019, 2019
Huan Yu, Lili Ren, Xiangpeng Huang, Mingjie Xie, Jun He, and Hang Xiao
Atmos. Chem. Phys., 19, 4025–4039, https://doi.org/10.5194/acp-19-4025-2019, https://doi.org/10.5194/acp-19-4025-2019, 2019
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Iodine is an essential trace element for mammals and aquatic plants. Increasing alga populations due to serious eutrophication in the coastal waters of China promote iodine emission. China contributes about 60 % of the global cultivated seaweed production. Iodine is likely emitted to the atmosphere and transformed into nanoparticles during the farming, harvesting, and processing of seaweed. Wild and farmed algae make the coastal area of China a potential hotspot of new particle formation.
Kate R. Smith, Peter M. Edwards, Peter D. Ivatt, James D. Lee, Freya Squires, Chengliang Dai, Richard E. Peltier, Mat J. Evans, Yele Sun, and Alastair C. Lewis
Atmos. Meas. Tech., 12, 1325–1336, https://doi.org/10.5194/amt-12-1325-2019, https://doi.org/10.5194/amt-12-1325-2019, 2019
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Clusters of low-cost, low-power atmospheric gas sensors were built into a sensor instrument to monitor NO2 and O3 in Beijing, alongside reference instruments, aiming to improve the reliability of sensor measurements. Clustering identical sensors and using the median sensor signal was used to minimize drift over short and medium timescales. Three different machine learning techniques were used for all the sensor data in an attempt to correct for cross-interferences, which worked to some degree.
Shan Zhou, Sonya Collier, Daniel A. Jaffe, and Qi Zhang
Atmos. Chem. Phys., 19, 1571–1585, https://doi.org/10.5194/acp-19-1571-2019, https://doi.org/10.5194/acp-19-1571-2019, 2019
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Regional background aerosols in the western US were studied from a mountaintop observatory during summer. Oxygenated organics and sulfate were dominant aerosol components. However, free tropospheric aerosols were more enriched in sulfate, frequently acidic, and comprised mainly of highly oxidized low-volatility organic species. In contrast, organic aerosols in the boundary-layer-influenced air masses were less oxidized and appeared to be semivolatile.
Shaojie Song, Meng Gao, Weiqi Xu, Yele Sun, Douglas R. Worsnop, John T. Jayne, Yuzhong Zhang, Lei Zhu, Mei Li, Zhen Zhou, Chunlei Cheng, Yibing Lv, Ying Wang, Wei Peng, Xiaobin Xu, Nan Lin, Yuxuan Wang, Shuxiao Wang, J. William Munger, Daniel J. Jacob, and Michael B. McElroy
Atmos. Chem. Phys., 19, 1357–1371, https://doi.org/10.5194/acp-19-1357-2019, https://doi.org/10.5194/acp-19-1357-2019, 2019
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Chemistry responsible for sulfate production in northern China winter haze remains mysterious. We propose a potentially key pathway through the reaction of formaldehyde and sulfur dioxide that has not been accounted for in previous studies. The special atmospheric conditions favor the formation and existence of their complex, hydroxymethanesulfonate (HMS).
Jun Chen, Zhanqing Li, Min Lv, Yuying Wang, Wei Wang, Yingjie Zhang, Haofei Wang, Xing Yan, Yele Sun, and Maureen Cribb
Atmos. Chem. Phys., 19, 1327–1342, https://doi.org/10.5194/acp-19-1327-2019, https://doi.org/10.5194/acp-19-1327-2019, 2019
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The hygroscopic growth function of aerosol particles is derived from Raman lidar, whose dependence on aerosol chemical composition is investigated using data from an aerosol chemical speciation monitor (ACSM) and a hygroscopic tandem differential mobility analyzer (H-TDMA) deployed in China. Two distinct cases were chosen with marked differences in their hygroscopic growth, which was fitted by the Kasten model. The differences were attributed to different amounts of chemical species.
Yanqing An, Jianzhong Xu, Lin Feng, Xinghua Zhang, Yanmei Liu, Shichang Kang, Bin Jiang, and Yuhong Liao
Atmos. Chem. Phys., 19, 1115–1128, https://doi.org/10.5194/acp-19-1115-2019, https://doi.org/10.5194/acp-19-1115-2019, 2019
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Detailed molecular chemical composition of water-soluble organic matter in the Himalayas was characterized by positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry for the first time. Many products formed from biogenic volatile organic compounds and biomass-burning-emitted compounds were found in the organic compounds, suggesting the important contribution of these two sources in the Himalayas.
Junfeng Wang, Dantong Liu, Xinlei Ge, Yangzhou Wu, Fuzhen Shen, Mindong Chen, Jian Zhao, Conghui Xie, Qingqing Wang, Weiqi Xu, Jie Zhang, Jianlin Hu, James Allan, Rutambhara Joshi, Pingqing Fu, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 447–458, https://doi.org/10.5194/acp-19-447-2019, https://doi.org/10.5194/acp-19-447-2019, 2019
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This work is part of the UK-China APHH campaign. We used a laser-only Aerodyne soot particle aerosol mass spectrometer, for the first time, to investigate the concentrations, size distributions and chemical compositions for those ambient submicron aerosol particles only with black carbon as cores. Our findings are valuable to understand the BC properties and processes in the densely populated megacities.
Qiang Huang, Jiubin Chen, Weilin Huang, John R. Reinfelder, Pingqing Fu, Shengliu Yuan, Zhongwei Wang, Wei Yuan, Hongming Cai, Hong Ren, Yele Sun, and Li He
Atmos. Chem. Phys., 19, 315–325, https://doi.org/10.5194/acp-19-315-2019, https://doi.org/10.5194/acp-19-315-2019, 2019
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Although the specific reactions and mechanisms in fine aerosols could not be explicitly determined from this field study, our results provide isotopic evidence that local daily photochemical reduction of divalent Hg is of critical importance to the fate of PM2.5-Hg in urban atmospheres and that, in addition to variation in sources, photochemical reduction appears to be an important process that affects both the particle mass-specific abundance and isotopic composition of PM2.5-Hg.
Conghui Xie, Weiqi Xu, Junfeng Wang, Qingqing Wang, Dantong Liu, Guiqian Tang, Ping Chen, Wei Du, Jian Zhao, Yingjie Zhang, Wei Zhou, Tingting Han, Qingyun Bian, Jie Li, Pingqing Fu, Zifa Wang, Xinlei Ge, James Allan, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 165–179, https://doi.org/10.5194/acp-19-165-2019, https://doi.org/10.5194/acp-19-165-2019, 2019
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We present the first simultaneous real-time online measurements of aerosol optical properties at ground level and at 260 m on a meteorological tower in urban Beijing in winter. The vertical similarities and differences in scattering and absorption coefficients were characterized. The increases in MAC of BC were mainly associated with the coating materials on rBC. Coal combustion was the dominant source contribution of brown carbon followed by biomass burning and SOA in winter in Beijing.
Peng Sun, Wei Nie, Xuguang Chi, Yuning Xie, Xin Huang, Zheng Xu, Ximeng Qi, Zhengning Xu, Lei Wang, Tianyi Wang, Qi Zhang, and Aijun Ding
Atmos. Chem. Phys., 18, 17177–17190, https://doi.org/10.5194/acp-18-17177-2018, https://doi.org/10.5194/acp-18-17177-2018, 2018
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A total of 2 years of online measurement of particulate nitrate was conducted at the SORPES station in the western Yangtze River Delta, eastern China. Nitrate was found to be the major driver of haze pollution and behaved differently in different seasons. In summer, thermodynamic equilibrium and photochemical processes controlled nitrate formation. In winter, N2O5 hydrolysis was demonstrated to be a major contributor to the nitrate episodes.
Yangyang Zhang, Aohan Tang, Dandan Wang, Qingqing Wang, Katie Benedict, Lin Zhang, Duanyang Liu, Yi Li, Jeffrey L. Collett Jr., Yele Sun, and Xuejun Liu
Atmos. Chem. Phys., 18, 16385–16398, https://doi.org/10.5194/acp-18-16385-2018, https://doi.org/10.5194/acp-18-16385-2018, 2018
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Our study is the first to continually monitor the vertical concentration profile of NH3 in urban Beijing. Weekly concentrations averaged 13.3 ± 4.8 μg m−3. The highest NH3 concentrations were always observed between 32 and 63 m, decreasing toward the surface and toward higher altitudes. Our results demonstrate a NH3 rich atmosphere in urban Beijing, from the ground to at least 320 m. Regional transport from the south (intensive agricultural regions) contributed high NH3 concentrations in Beijing.
Yingjie Zhang, Wei Du, Yuying Wang, Qingqing Wang, Haofei Wang, Haitao Zheng, Fang Zhang, Hongrong Shi, Yuxuan Bian, Yongxiang Han, Pingqing Fu, Francesco Canonaco, André S. H. Prévôt, Tong Zhu, Pucai Wang, Zhanqing Li, and Yele Sun
Atmos. Chem. Phys., 18, 14637–14651, https://doi.org/10.5194/acp-18-14637-2018, https://doi.org/10.5194/acp-18-14637-2018, 2018
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We have a comprehensive characterization of aerosol chemistry and particle growth events at a downwind site of a highly polluted city in the North China Plain. Aerosol particles at the urban downwind site were highly aged and mainly from secondary formation. New particle growth events were also frequently observed on both clean and polluted days. While both sulfate and SOA played important roles in particle growth during clean periods, SOA was more important than sulfate during polluted events.
Lei Liu, Jian Zhang, Liang Xu, Qi Yuan, Dao Huang, Jianmin Chen, Zongbo Shi, Yele Sun, Pingqing Fu, Zifa Wang, Daizhou Zhang, and Weijun Li
Atmos. Chem. Phys., 18, 14681–14693, https://doi.org/10.5194/acp-18-14681-2018, https://doi.org/10.5194/acp-18-14681-2018, 2018
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Using transmission electron microscopy, we studied individual cloud droplet residual and interstitial particles collected in cloud events at Mt. Tai in the polluted North China region. We found that individual cloud droplets were an extremely complicated mixture containing abundant refractory soot (i.e., black carbon), fly ash, and metals. The complicated cloud droplets have not been reported in clean continental or marine air before.
Mingjie Kang, Pingqing Fu, Kimitaka Kawamura, Fan Yang, Hongliang Zhang, Zhengchen Zang, Hong Ren, Lujie Ren, Ye Zhao, Yele Sun, and Zifa Wang
Atmos. Chem. Phys., 18, 13947–13967, https://doi.org/10.5194/acp-18-13947-2018, https://doi.org/10.5194/acp-18-13947-2018, 2018
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Molecular characterization and spatial distribution of biogenic primary organic aerosol (POA) and secondary organic aerosol (SOA) in the marine atmosphere are not well known. Here, we analysed the organic molecular composition of marine aerosols collected during a marine cruise in the East China Sea during May–June 2014. Our results suggest that the Asian continent can be a natural emitter of biogenic POA and SOA, which can be transported to the downwind marine atmosphere.
Yuying Wang, Zhanqing Li, Yingjie Zhang, Wei Du, Fang Zhang, Haobo Tan, Hanbing Xu, Tianyi Fan, Xiaoai Jin, Xinxin Fan, Zipeng Dong, Qiuyan Wang, and Yele Sun
Atmos. Chem. Phys., 18, 11739–11752, https://doi.org/10.5194/acp-18-11739-2018, https://doi.org/10.5194/acp-18-11739-2018, 2018
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Very different aerosol hygroscopicities and mixing states were found at these sites in the North China Plain. The PDF for 40–200 nm particles showed the particles were highly aged and internally mixed at Xingtai because of high pollution and strong photochemical reactions. A good proxy for the chemical comical composition (kappa = 0.31) in calculating CCN concentration was found. Importantly, our study investigated the influence of industrial emissions on the aerosol properties.
Wei Zhou, Jian Zhao, Bin Ouyang, Archit Mehra, Weiqi Xu, Yuying Wang, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Qi Chen, Conghui Xie, Qingqing Wang, Junfeng Wang, Wei Du, Yingjie Zhang, Xinlei Ge, Penglin Ye, James D. Lee, Pingqing Fu, Zifa Wang, Douglas Worsnop, Roderic Jones, Carl J. Percival, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 18, 11581–11597, https://doi.org/10.5194/acp-18-11581-2018, https://doi.org/10.5194/acp-18-11581-2018, 2018
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We present measurements of gas-phase N2O5 and ClNO2 by ToF-CIMS during summer in urban Beijing as part of the APHH campaign. High reactivity of N2O5 indicative of active nocturnal chemistry was observed. The lifetime of N2O5 as a function of aerosol surface area and relative humidity was characterized, and N2O5 uptake coefficients were estimated. We also found that the N2O5 loss in this study is mainly attributed to its indirect loss via reactions of NO3 with VOCs and NO.
Yele Sun, Weiqi Xu, Qi Zhang, Qi Jiang, Francesco Canonaco, André S. H. Prévôt, Pingqing Fu, Jie Li, John Jayne, Douglas R. Worsnop, and Zifa Wang
Atmos. Chem. Phys., 18, 8469–8489, https://doi.org/10.5194/acp-18-8469-2018, https://doi.org/10.5194/acp-18-8469-2018, 2018
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We present a 2–year analysis of organic aerosol (OA) from highly time–resolved measurements by an aerosol chemical speciation monitor in the megacity of Beijing. The sources of OA were analyzed with the advanced factor analysis of a multilinear engine (ME-2). Our results showed very different seasonal patterns, relative humidity and temperature dependence, and sources regions among different OA factors. The sources and processes of OA factors, and their roles in haze pollution are elucidated.
Jie Zhang, Sara Lance, Jeffrey M. Freedman, Yele Sun, Brian A. Crandall, Xiuli Wei, and James J. Schwab
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-529, https://doi.org/10.5194/acp-2018-529, 2018
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The impact of fireworks (FW) events on air quality was studied using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and collocated instruments during the Independence Day (July 4) holiday. The Independence Day FW events resulted in significant increases in both organic and inorganic (potassium, sulfate, chloride) chemical components, and the contribution from different aerosol sources was discussed.
Shaojie Song, Meng Gao, Weiqi Xu, Jingyuan Shao, Guoliang Shi, Shuxiao Wang, Yuxuan Wang, Yele Sun, and Michael B. McElroy
Atmos. Chem. Phys., 18, 7423–7438, https://doi.org/10.5194/acp-18-7423-2018, https://doi.org/10.5194/acp-18-7423-2018, 2018
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Severe haze events occur frequently over northern China, especially in winter. Acidity plays a critical role in the formation of secondary PM2.5 and its toxicity. Using field measurements of gases and particles to critically evaluate two thermodynamic models routinely employed to determine particle acidity, we found that China's winter haze particles are generally within a moderately acidic range (pH 4–5) and not highly acidic (0) or neutral (7) as has been previously reported in the literature.
Hwajin Kim, Qi Zhang, and Jongbae Heo
Atmos. Chem. Phys., 18, 7149–7168, https://doi.org/10.5194/acp-18-7149-2018, https://doi.org/10.5194/acp-18-7149-2018, 2018
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Aerosol chemistry, sources and processes driving the observed temporal and diurnal variations of PM were studied in the Seoul Metropolitan Area (SMA) during spring 2016. An in-depth analysis of the data uncovered that air quality in SMA was influenced strongly by secondary aerosol formation. Also, it was found that the haze episode during spring was mainly caused by a combination of both regional and local factors, which is different from the winter haze mainly caused by intense local sources.
Jingye Ren, Fang Zhang, Yuying Wang, Don Collins, Xinxin Fan, Xiaoai Jin, Weiqi Xu, Yele Sun, Maureen Cribb, and Zhanqing Li
Atmos. Chem. Phys., 18, 6907–6921, https://doi.org/10.5194/acp-18-6907-2018, https://doi.org/10.5194/acp-18-6907-2018, 2018
Dean B. Atkinson, Mikhail Pekour, Duli Chand, James G. Radney, Katheryn R. Kolesar, Qi Zhang, Ari Setyan, Norman T. O'Neill, and Christopher D. Cappa
Atmos. Chem. Phys., 18, 5499–5514, https://doi.org/10.5194/acp-18-5499-2018, https://doi.org/10.5194/acp-18-5499-2018, 2018
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We use in situ measurements of particle light extinction to assess the performance of a typical aerosol remote retrieval method. The retrieved fine-mode fraction of extinction, a property commonly used to characterize the anthropogenic influence on the aerosol optical depth, compares well with the in situ measurements as does the retrieved effective fine-mode radius, which characterizes the average size of the particles that contribute most to scattering.
Xinghua Zhang, Jianzhong Xu, Shichang Kang, Yanmei Liu, and Qi Zhang
Atmos. Chem. Phys., 18, 4617–4638, https://doi.org/10.5194/acp-18-4617-2018, https://doi.org/10.5194/acp-18-4617-2018, 2018
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Highly time and chemically resolved submicron aerosol properties were characterized online for the first time in a high-altitude site (Qomolangma station, 4276 m a.s.l.) in the northern Himalayas by using the Aerodyne HR-ToF-AMS. Biomass burning plumes were frequently observed and the dynamic processes (emissions, transport, and chemical processing) were characterized. The source and chemical composition of organic aerosol were further elucidated using positive matrix factorization analysis.
Wei Zhou, Qingqing Wang, Xiujuan Zhao, Weiqi Xu, Chen Chen, Wei Du, Jian Zhao, Francesco Canonaco, André S. H. Prévôt, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 18, 3951–3968, https://doi.org/10.5194/acp-18-3951-2018, https://doi.org/10.5194/acp-18-3951-2018, 2018
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We present a 3-month analysis of submicron aerosols that were measured at 260 m on a meteorological tower in Beijing, China. The sources of organic aerosol (OA) were analyzed by using a multi-linear engine (ME-2). Our results showed significant changes in both primary and secondary OA composition from the non-heating season to the heating season. We also observed a considerable contribution (10–13%) of cooking OA at 260 m and very different OA composition between ground level and 260 m.
Wanyu Zhao, Kimitaka Kawamura, Siyao Yue, Lianfang Wei, Hong Ren, Yu Yan, Mingjie Kang, Linjie Li, Lujie Ren, Senchao Lai, Jie Li, Yele Sun, Zifa Wang, and Pingqing Fu
Atmos. Chem. Phys., 18, 2749–2767, https://doi.org/10.5194/acp-18-2749-2018, https://doi.org/10.5194/acp-18-2749-2018, 2018
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In this paper, we investigate the seasonal trends in concentrations and compound-specific stable carbon isotope ratios of low molecular weight dicarboxylic acids (C2–C12) and related compounds in fine aerosols (PM2.5) in Beijing. Our study demonstrates that, in addition to the production via photo-oxidation, high abundances of diacids and related compounds in Beijing are largely associated with anthropogenic primary emissions such as biomass burning, fossil fuel combustion and plastic burning.
Qingqing Wang, Yele Sun, Weiqi Xu, Wei Du, Libo Zhou, Guiqian Tang, Chen Chen, Xueling Cheng, Xiujuan Zhao, Dongsheng Ji, Tingting Han, Zhe Wang, Jie Li, and Zifa Wang
Atmos. Chem. Phys., 18, 2495–2509, https://doi.org/10.5194/acp-18-2495-2018, https://doi.org/10.5194/acp-18-2495-2018, 2018
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We conducted the first real-time continuous vertical measurements of particle extinction, NO2, and BC from ground level to 260 m during two severe winter haze episodes in urban Beijing, China. Our results show very complex and dynamic vertical profiles that interact closely with boundary layer and meteorological conditions. Further analysis demonstrate that vertical convection, temperature inversion, and local emissions are three major factors affecting the changes in vertical profiles.
Yangzhou Wu, Xinlei Ge, Junfeng Wang, Yafei Shen, Zhaolian Ye, Shun Ge, Yun Wu, Huan Yu, and Mindong Chen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-75, https://doi.org/10.5194/acp-2018-75, 2018
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This work presents results regarding the secondary aerosol formations in suburan Nanjing, a site downwind of an industrial zone. We show that under such an industrialized environment, secondary species overwhelmingly dominate the fine particle mass, and moisture (relative humidity) is critical in enhancing formations of sulfate, nitrate and the most oxygenated portion of OA, while less oxygenated secondary OA was mainly driven by photochemical processing.
Jianzhong Xu, Qi Zhang, Jinsen Shi, Xinlei Ge, Conghui Xie, Junfeng Wang, Shichang Kang, Ruixiong Zhang, and Yuhang Wang
Atmos. Chem. Phys., 18, 427–443, https://doi.org/10.5194/acp-18-427-2018, https://doi.org/10.5194/acp-18-427-2018, 2018
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This manuscript presents results from a comprehensive field study using an HR-AMS coupled with a suite of other instruments in central Tibetan Plateau. The study discusses the chemical composition, sources, and processes of submicron aerosol during the transition from pre-monsoon to monsoon. Organic aerosol was overall highly oxidized during the entire study with higher O / C ratios during the pre-monsoon period. Sensitivity of air pollution transport with synoptic process was also evaluated.
Lin Feng, Yanqing An, Jianzhong Xu, Shichang Kang, Xiaofei Li, Yongqiang Zhou, Yunlin Zhang, Bin Jiang, and Yuhong Liao
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-507, https://doi.org/10.5194/bg-2017-507, 2017
Revised manuscript not accepted
Zheng Fang, Wei Deng, Yanli Zhang, Xiang Ding, Mingjin Tang, Tengyu Liu, Qihou Hu, Ming Zhu, Zhaoyi Wang, Weiqiang Yang, Zhonghui Huang, Wei Song, Xinhui Bi, Jianmin Chen, Yele Sun, Christian George, and Xinming Wang
Atmos. Chem. Phys., 17, 14821–14839, https://doi.org/10.5194/acp-17-14821-2017, https://doi.org/10.5194/acp-17-14821-2017, 2017
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Primary emissions and aging of open straw burning plumes were characterized in ambient dilution conditions in a chamber. Rich in alkenes, the plumes have high O3 formation potential. The emissions of specific particulate and gaseous compounds were less when the straws were fully burned. Organic aerosol (OA) mass increased by a factor of 2–8 with 3–9 h photo-oxidation, yet > 70 % of the mass cannot be explained by the known precursors. OA gained more O- and N-containing compounds during aging.
Gouri Prabhakar, Caroline L. Parworth, Xiaolu Zhang, Hwajin Kim, Dominique E. Young, Andreas J. Beyersdorf, Luke D. Ziemba, John B. Nowak, Timothy H. Bertram, Ian C. Faloona, Qi Zhang, and Christopher D. Cappa
Atmos. Chem. Phys., 17, 14747–14770, https://doi.org/10.5194/acp-17-14747-2017, https://doi.org/10.5194/acp-17-14747-2017, 2017
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This work assesses the processes that control the ambient concentrations of particulate nitrate in the the wintertime San Joaquin Valley of California through a combination of aircraft and surface measurements made during the DISCOVER-AQ study. We provide an observational demonstration of how nocturnal production and advection in aloft layers combines with daytime production and loss from entrainment and deposition to give rise to a distinct diurnal profile in surface nitrate concentrations.
Yunjiang Zhang, Lili Tang, Philip L. Croteau, Olivier Favez, Yele Sun, Manjula R. Canagaratna, Zhuang Wang, Florian Couvidat, Alexandre Albinet, Hongliang Zhang, Jean Sciare, André S. H. Prévôt, John T. Jayne, and Douglas R. Worsnop
Atmos. Chem. Phys., 17, 14501–14517, https://doi.org/10.5194/acp-17-14501-2017, https://doi.org/10.5194/acp-17-14501-2017, 2017
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We conducted the first field measurements of non-refractory fine aerosols (NR-PM2.5) in a megacity of eastern China using a PM2.5-ACSM along with a PM1-ACSM measurement. Inter-comparisons demonstrated that the NR-PM2.5 components can be characterized. Substantial mass fractions of aerosol species were observed in the size range of 1–2.5 μm, with sulfate and SOA being the two largest contributors. The impacts of aerosol water driven by secondary inorganic aerosols on SOA formation were explored.
Benjamin N. Murphy, Matthew C. Woody, Jose L. Jimenez, Ann Marie G. Carlton, Patrick L. Hayes, Shang Liu, Nga L. Ng, Lynn M. Russell, Ari Setyan, Lu Xu, Jeff Young, Rahul A. Zaveri, Qi Zhang, and Havala O. T. Pye
Atmos. Chem. Phys., 17, 11107–11133, https://doi.org/10.5194/acp-17-11107-2017, https://doi.org/10.5194/acp-17-11107-2017, 2017
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We incorporate recent findings about the behavior of organic pollutants in urban airsheds into the Community Multiscale Air Quality (CMAQ) model to refine predictions of organic particulate pollution in the United States. The new techniques, which account for the volatility and ongoing chemistry of airborne organic compounds, substantially reduce biases, particularly in the winter time and near emission sources.
Jinghao Zhai, Xiaohui Lu, Ling Li, Qi Zhang, Ci Zhang, Hong Chen, Xin Yang, and Jianmin Chen
Atmos. Chem. Phys., 17, 7481–7493, https://doi.org/10.5194/acp-17-7481-2017, https://doi.org/10.5194/acp-17-7481-2017, 2017
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The effective density, chemical composition, and optical properties of particles produced by burning rice straw were measured. Density distribution and single-particle mass spectrometry showed the size-dependent external mixing of black carbon, organic carbon, and potassium salts in biomass burning particles. Optical measurements indicated the significant presence of brown carbon in all particles. Though freshly emitted, light absorption enhancement was observed for particles larger than 200 nm.
Wei Du, Jian Zhao, Yuying Wang, Yingjie Zhang, Qingqing Wang, Weiqi Xu, Chen Chen, Tingting Han, Fang Zhang, Zhanqing Li, Pingqing Fu, Jie Li, Zifa Wang, and Yele Sun
Atmos. Chem. Phys., 17, 6797–6811, https://doi.org/10.5194/acp-17-6797-2017, https://doi.org/10.5194/acp-17-6797-2017, 2017
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We conducted the first simultaneous measurements of size-resolved particle number concentrations at ground level and 260 m in urban Beijing. The vertical differences strongly depend on particle sizes, with accumulation-mode particles being highly correlated at the two heights. We further demonstrated that regional emission controls have a dominant impact on accumulation-mode particles, while the influences on Aitken particles were much smaller due to the enhanced NPF events.
Ting Yang, Zifa Wang, Wei Zhang, Alex Gbaguidi, Nobuo Sugimoto, Xiquan Wang, Ichiro Matsui, and Yele Sun
Atmos. Chem. Phys., 17, 6215–6225, https://doi.org/10.5194/acp-17-6215-2017, https://doi.org/10.5194/acp-17-6215-2017, 2017
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Predicting air pollution events over megacities requires, notably, continuous and accurate determination of the boundary layer height (BLH). Based on gravity wave theory, a new approach (CRGM) is developed to overcome existing algorithms' weakness in order to accurately reproduce the fluctuations of the BLH under various atmospheric pollution conditions from lidar observation. Comprehensive evaluation highlights strong effectiveness of this new method.
Yuying Wang, Fang Zhang, Zhanqing Li, Haobo Tan, Hanbing Xu, Jingye Ren, Jian Zhao, Wei Du, and Yele Sun
Atmos. Chem. Phys., 17, 5239–5251, https://doi.org/10.5194/acp-17-5239-2017, https://doi.org/10.5194/acp-17-5239-2017, 2017
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A series of strict emission control measures were implemented in Beijing and the surrounding seven provinces to ensure good air quality during the 2015 China Victory Day parade, rendering a unique opportunity to investigate anthropogenic impact of aerosol properties. Submicron aerosol hygroscopicity and volatility were measured during and after the control period. By comparison we found aerosol particles became more hydrophobic and volatile due to the emission control measures.
Haiyan Li, Qi Zhang, Qiang Zhang, Chunrong Chen, Litao Wang, Zhe Wei, Shan Zhou, Caroline Parworth, Bo Zheng, Francesco Canonaco, André S. H. Prévôt, Ping Chen, Hongliang Zhang, Timothy J. Wallington, and Kebin He
Atmos. Chem. Phys., 17, 4751–4768, https://doi.org/10.5194/acp-17-4751-2017, https://doi.org/10.5194/acp-17-4751-2017, 2017
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The sources and aerosol evolution processes of severe pollution episodes were investigated in Handan during wintertime using real-time measurements. An in-depth analysis of the data uncovered that primary emissions from coal combustion and biomass burning together with secondary formation of sulfate (mainly from SO2 emitted by coal combustion) are important driving factors for haze evolution. Our findings provide useful insights into air pollution control in heavily polluted regions.
Jian Zhao, Wei Du, Yingjie Zhang, Qingqing Wang, Chen Chen, Weiqi Xu, Tingting Han, Yuying Wang, Pingqing Fu, Zifa Wang, Zhanqing Li, and Yele Sun
Atmos. Chem. Phys., 17, 3215–3232, https://doi.org/10.5194/acp-17-3215-2017, https://doi.org/10.5194/acp-17-3215-2017, 2017
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We conducted aerosol particle composition measurements at ground level and 260 m with two aerosol mass spectrometers in Beijing during the 2015 China Victory Day parade. Our results showed a stronger impact of emission controls on inorganic aerosol than OA. A larger decrease in more oxidized SOA than the less oxidized one during the control period was also observed. Our results indicate that emission controls and the changes in meteorological conditions have affected SOA formation mechanisms.
Zhaolian Ye, Jiashu Liu, Aijun Gu, Feifei Feng, Yuhai Liu, Chenglu Bi, Jianzhong Xu, Ling Li, Hui Chen, Yanfang Chen, Liang Dai, Quanfa Zhou, and Xinlei Ge
Atmos. Chem. Phys., 17, 2573–2592, https://doi.org/10.5194/acp-17-2573-2017, https://doi.org/10.5194/acp-17-2573-2017, 2017
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This work performed a thorough chemical characterization on the fine particulate matter (PM2.5) samples, collected during July 2015 to April 2016 across four seasons in Changzhou for the first time. In particular, an Aerodyne soot particle aerosol mass spectrometer (SP-AMS) was deployed offline to probe the chemical properties and sources of the water-soluble fraction of organic aerosols (WSOAs).
Shan Zhou, Sonya Collier, Daniel A. Jaffe, Nicole L. Briggs, Jonathan Hee, Arthur J. Sedlacek III, Lawrence Kleinman, Timothy B. Onasch, and Qi Zhang
Atmos. Chem. Phys., 17, 2477–2493, https://doi.org/10.5194/acp-17-2477-2017, https://doi.org/10.5194/acp-17-2477-2017, 2017
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Wildfire plumes in the western US were sampled at a high-elevation site in summer 2013. Three distinct BBOA types were identified, representing biomass burning OA with different degrees of atmospheric processing. Analysis of consecutive BB plumes transported from the same fire source showed that photooxidation led to enhanced mass fractions of aged BBOAs but negligible net OA production. A possible reason is that SOA formation was almost entirely balanced by BBOA volatilization during transport.
Jenni Kontkanen, Katrianne Lehtipalo, Lauri Ahonen, Juha Kangasluoma, Hanna E. Manninen, Jani Hakala, Clémence Rose, Karine Sellegri, Shan Xiao, Lin Wang, Ximeng Qi, Wei Nie, Aijun Ding, Huan Yu, Shanhu Lee, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 17, 2163–2187, https://doi.org/10.5194/acp-17-2163-2017, https://doi.org/10.5194/acp-17-2163-2017, 2017
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The concentrations of ~1–3 nm particles were investigated at nine sites around the world. Sub-3 nm particle concentrations were highest at the sites with strong anthropogenic influence. Electrically neutral particles dominated sub-3 nm particle concentrations in polluted environments and in boreal forest during spring and summer. Sub-3 nm particle concentrations were observed to be determined by the availability of precursor vapors rather than the sink caused by preexisting aerosol particles.
Hwajin Kim, Qi Zhang, Gwi-Nam Bae, Jin Young Kim, and Seung Bok Lee
Atmos. Chem. Phys., 17, 2009–2033, https://doi.org/10.5194/acp-17-2009-2017, https://doi.org/10.5194/acp-17-2009-2017, 2017
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We discuss characteristics, sources, and size distributions of the PM1 composition and OA components in Seoul, Korea, in winter. The serious pollution observed was caused by a combination of various factors, including meteorological conditions, emissions from local primary sources, secondary formation, and transport of air masses from upwind locations. This will be very useful for enacting effective PM reduction strategies for Korea as well as for the broader northern pan-Eurasian region.
Shurui Chen, Liang Xu, Yinxiao Zhang, Bing Chen, Xinfeng Wang, Xiaoye Zhang, Mei Zheng, Jianmin Chen, Wenxing Wang, Yele Sun, Pingqing Fu, Zifa Wang, and Weijun Li
Atmos. Chem. Phys., 17, 1259–1270, https://doi.org/10.5194/acp-17-1259-2017, https://doi.org/10.5194/acp-17-1259-2017, 2017
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Many studies have focused on the unusually severe hazes instead of the more frequent light and moderate hazes (22–63 %) in winter in the North China Plain (NCP). The morphology, mixing state, and size of organic aerosols in the L & M hazes were characterized. We conclude that the direct emissions from residential coal stoves without any pollution controls in rural and urban outskirts contribute large amounts of primary OM particles to the regional L & M hazes in winter in the NCP.
Jianlin Hu, Peng Wang, Qi Ying, Hongliang Zhang, Jianjun Chen, Xinlei Ge, Xinghua Li, Jingkun Jiang, Shuxiao Wang, Jie Zhang, Yu Zhao, and Yingyi Zhang
Atmos. Chem. Phys., 17, 77–92, https://doi.org/10.5194/acp-17-77-2017, https://doi.org/10.5194/acp-17-77-2017, 2017
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An annual simulation of secondary organic aerosol (SOA) concentrations in China with updated SOA formation pathways reveals that SOA can be a significant contributor to PM2.5 in major urban areas. Summer SOA is dominated by emissions from biogenic sources, while winter SOA is dominated by anthropogenic emissions such as alkanes and aromatic compounds. Reactive surface uptake of dicarbonyls throughout the year and isoprene epoxides in summer is the most important contributor.
Jianzhong Xu, Jinsen Shi, Qi Zhang, Xinlei Ge, Francesco Canonaco, André S. H. Prévôt, Matthias Vonwiller, Sönke Szidat, Jinming Ge, Jianmin Ma, Yanqing An, Shichang Kang, and Dahe Qin
Atmos. Chem. Phys., 16, 14937–14957, https://doi.org/10.5194/acp-16-14937-2016, https://doi.org/10.5194/acp-16-14937-2016, 2016
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This study deployed an AMS field study in Lanzhou, a city in northwestern China, evaluating the chemical composition, sources, and processes of urban aerosols during wintertime. In comparison with the results during summer in Lanzhou, the air pollution during winter was more severe and the sources were more complex. In addition, this paper estimates the contributions of fossil and non-fossil sources of organic carbon to primary and secondary organic carbon using the carbon isotopic method.
Biwu Chu, Xiao Zhang, Yongchun Liu, Hong He, Yele Sun, Jingkun Jiang, Junhua Li, and Jiming Hao
Atmos. Chem. Phys., 16, 14219–14230, https://doi.org/10.5194/acp-16-14219-2016, https://doi.org/10.5194/acp-16-14219-2016, 2016
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The interactive effects between inorganic and organic species under highly complex pollution conditions remain uncertain and were studied in a smog chamber. This study indicated that the synergistic formation of secondary inorganic and organic aerosol might increase the secondary aerosol load in the atmosphere and contribute haze pollution in eastern China. These synergistic effects were related to the heterogeneous process on aerosol surface and need to be considered in air quality models.
Yele Sun, Wei Du, Pingqing Fu, Qingqing Wang, Jie Li, Xinlei Ge, Qi Zhang, Chunmao Zhu, Lujie Ren, Weiqi Xu, Jian Zhao, Tingting Han, Douglas R. Worsnop, and Zifa Wang
Atmos. Chem. Phys., 16, 8309–8329, https://doi.org/10.5194/acp-16-8309-2016, https://doi.org/10.5194/acp-16-8309-2016, 2016
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We have a comprehensive characterization of the sources, variations and processes of submicron aerosols in Beijing in winter using HR-AMS and GC/MS measurements. The primary sources including traffic, cooking, biomass burning and coal combustion emissions, and secondary components were separated and quantified with PMF. Our results elucidated the important roles of primary emissions, particularly coal combustion, and aqueous-phase processing in the formation of severe air pollution in winter.
Christopher D. Cappa, Katheryn R. Kolesar, Xiaolu Zhang, Dean B. Atkinson, Mikhail S. Pekour, Rahul A. Zaveri, Alla Zelenyuk, and Qi Zhang
Atmos. Chem. Phys., 16, 6511–6535, https://doi.org/10.5194/acp-16-6511-2016, https://doi.org/10.5194/acp-16-6511-2016, 2016
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Measurements of size-dependent aerosol optical properties at visible wavelengths made during the 2010 CARES study are reported on, with a special focus on the characterization of supermicron particles. The relationships with and dependence upon particle composition, particle size, photochemical aging, water uptake and heating are discussed, along with broader implications of these in situ measurements for the interpretation of remote sensing products.
Fang Zhang, Zhanqing Li, Yanan Li, Yele Sun, Zhenzhu Wang, Ping Li, Li Sun, Pucai Wang, Maureen Cribb, Chuanfeng Zhao, Tianyi Fan, Xin Yang, and Qingqing Wang
Atmos. Chem. Phys., 16, 5413–5425, https://doi.org/10.5194/acp-16-5413-2016, https://doi.org/10.5194/acp-16-5413-2016, 2016
Dominique E. Young, Hwajin Kim, Caroline Parworth, Shan Zhou, Xiaolu Zhang, Christopher D. Cappa, Roger Seco, Saewung Kim, and Qi Zhang
Atmos. Chem. Phys., 16, 5427–5451, https://doi.org/10.5194/acp-16-5427-2016, https://doi.org/10.5194/acp-16-5427-2016, 2016
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Aerosol chemistry and the sources and processes driving the observed temporal and diurnal variations of PM were studied in a polluted urban environment during winter 2013. These results were compared to a similar campaign from winter 2010. Meteorology strongly influenced PM composition, both directly and indirectly. Nighttime reactions played a more important role in 2013 and the influence from a nighttime formed residual layer that mixed down in the morning was also much more intense in 2013.
Lu Yu, Jeremy Smith, Alexander Laskin, Katheryn M. George, Cort Anastasio, Julia Laskin, Ann M. Dillner, and Qi Zhang
Atmos. Chem. Phys., 16, 4511–4527, https://doi.org/10.5194/acp-16-4511-2016, https://doi.org/10.5194/acp-16-4511-2016, 2016
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The chemical evolution of SOA formed during aqueous reactions of phenolic compounds is studied via combined bulk and molecular analysis. Phenolic SOA evolve dynamically during photochemical aging, with different reaction mechanisms (oligomerization, fragmentation, and functionalization) leading to different generations of products that span an enormous range in volatilities and a large range in oxidation state and composition. Aqueous reactions of phenols are likely an important source of ELVOC.
Huan Yu, Luyu Zhou, Liang Dai, Wenchao Shen, Wei Dai, Jun Zheng, Yan Ma, and Mindong Chen
Atmos. Chem. Phys., 16, 2641–2657, https://doi.org/10.5194/acp-16-2641-2016, https://doi.org/10.5194/acp-16-2641-2016, 2016
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New particle formation is an important source of atmospheric aerosols. We conducted size- and time-dependent nucleation rate and growth rate measurements of sub-3 nm particles in the urban atmosphere. We observed that growth rate could be very high between 1 and 3 nm and did not increase monotonically with particle size. This was interpreted as the solvation effect of organic vapor in inorganic nuclei. The growth rate behavior gives new insight into cluster dynamics in polluted environments.
S. E. Pusede, K. C. Duffey, A. A. Shusterman, A. Saleh, J. L. Laughner, P. J. Wooldridge, Q. Zhang, C. L. Parworth, H. Kim, S. L. Capps, L. C. Valin, C. D. Cappa, A. Fried, J. Walega, J. B. Nowak, A. J. Weinheimer, R. M. Hoff, T. A. Berkoff, A. J. Beyersdorf, J. Olson, J. H. Crawford, and R. C. Cohen
Atmos. Chem. Phys., 16, 2575–2596, https://doi.org/10.5194/acp-16-2575-2016, https://doi.org/10.5194/acp-16-2575-2016, 2016
Wei Deng, Qihou Hu, Tengyu Liu, Xinming Wang, Yanli Zhang, Xiang Ding, Yele Sun, Xinhui Bi, Jianzhen Yu, Weiqiang Yang, Xinyu Huang, Zhou Zhang, Zhonghui Huang, Quanfu He, A. Mellouki, and Christian George
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-50, https://doi.org/10.5194/acp-2016-50, 2016
Revised manuscript not accepted
L. Kleinman, C. Kuang, A. Sedlacek, G. Senum, S. Springston, J. Wang, Q. Zhang, J. Jayne, J. Fast, J. Hubbe, J. Shilling, and R. Zaveri
Atmos. Chem. Phys., 16, 1729–1746, https://doi.org/10.5194/acp-16-1729-2016, https://doi.org/10.5194/acp-16-1729-2016, 2016
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Atmospheric measurements of total organic aerosol (OA) and tracers of anthropogenic and biogenic emissions are used to quantify synergistic effects (A–B interactions) between two classes of precursors in the formation of OA. Regressions are consistent with the Sacramento plume composed mainly of modern carbon, and OA correlating best with an anthropogenic tracer. It is found that meteorological conditions during a pollution episode can mimic effects of A–B interactions.
T. Liu, X. Wang, Q. Hu, W. Deng, Y. Zhang, X. Ding, X. Fu, F. Bernard, Z. Zhang, S. Lü, Q. He, X. Bi, J. Chen, Y. Sun, J. Yu, P. Peng, G. Sheng, and J. Fu
Atmos. Chem. Phys., 16, 675–689, https://doi.org/10.5194/acp-16-675-2016, https://doi.org/10.5194/acp-16-675-2016, 2016
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The formation of SOA and sulfate aerosols from the photooxidation of gasoline vehicle exhaust (GVE) when mixing with SO2 was investigated in a smog chamber. We found that the presence of GVE enhanced the conversion of SO2 to sulfate predominantly through reactions with stabilized Criegee intermediates. On the other hand, the elevated particle acidity enhanced the SOA production from GVE. This study indicated that SO2 and GVE could enhance each other in forming secondary aerosols.
W. Q. Xu, Y. L. Sun, C. Chen, W. Du, T. T. Han, Q. Q. Wang, P. Q. Fu, Z. F. Wang, X. J. Zhao, L. B. Zhou, D. S. Ji, P. C. Wang, and D. R. Worsnop
Atmos. Chem. Phys., 15, 13681–13698, https://doi.org/10.5194/acp-15-13681-2015, https://doi.org/10.5194/acp-15-13681-2015, 2015
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We have investigated the response of aerosol composition, size distributions, and oxidation properties to emission controls during the 2014 Asia- Pacific Economic Cooperation (APEC) summit in Beijing. Our results showed substantial changes of aerosol bulk composition during APEC with the most reductions in secondary aerosols in large accumulation modes, demonstrating that that emission controls over regional scales can substantially reduce secondary particulates.
W. J. Li, S. R. Chen, Y. S. Xu, X. C. Guo, Y. L. Sun, X. Y. Yang, Z. F. Wang, X. D. Zhao, J. M. Chen, and W. X. Wang
Atmos. Chem. Phys., 15, 13365–13376, https://doi.org/10.5194/acp-15-13365-2015, https://doi.org/10.5194/acp-15-13365-2015, 2015
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We found that anthropogenic soot, fly ash, and visible organic particles likely adhere to the surface of secondary inorganic particles larger than 200nm due to coagulation. Biomass burning and coal combustion both constantly contribute to anthropogenic particles in the Qinghai-Tibet Plateau (QTP) background atmosphere. Organic coating and soot on the surface of the aged particles could have different impacts on their hygroscopic and optical properties in the QTP compared to the urban aerosols.
C. Chen, Y. L. Sun, W. Q. Xu, W. Du, L. B. Zhou, T. T. Han, Q. Q. Wang, P. Q. Fu, Z. F. Wang, Z. Q. Gao, Q. Zhang, and D. R. Worsnop
Atmos. Chem. Phys., 15, 12879–12895, https://doi.org/10.5194/acp-15-12879-2015, https://doi.org/10.5194/acp-15-12879-2015, 2015
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A comprehensive characterization of submicron aerosol composition and sources at 260m in urban Beijing during APEC 2014 is presented. Aerosol species were shown to decrease substantially by 40–80% during APEC, whereas the bulk composition was relatively similar to the result of synergetic controls of secondary precursors. Our results elucidated that the good air quality during APEC was the combined result of emission controls and meteorological effects, with the former playing the dominant role.
A. Lupascu, R. Easter, R. Zaveri, M. Shrivastava, M. Pekour, J. Tomlinson, Q. Yang, H. Matsui, A. Hodzic, Q. Zhang, and J. D. Fast
Atmos. Chem. Phys., 15, 12283–12313, https://doi.org/10.5194/acp-15-12283-2015, https://doi.org/10.5194/acp-15-12283-2015, 2015
W. Du, Y. L. Sun, Y. S. Xu, Q. Jiang, Q. Q. Wang, W. Yang, F. Wang, Z. P. Bai, X. D. Zhao, and Y. C. Yang
Atmos. Chem. Phys., 15, 10811–10824, https://doi.org/10.5194/acp-15-10811-2015, https://doi.org/10.5194/acp-15-10811-2015, 2015
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A fall field campaign was conducted at a national background site (3295m a.s.l.) over the Tibetan Plateau. The submicron aerosol was dominated by organics (43%) and sulfate (28%). Secondary organic aerosol (SOA) dominated OA (85%), 17% of which being aged biomass burning OA. New particle formation and growth events were frequently observed, with an average particle growth rate of 2.0nm per hour. The important role of organics in particle growth in the Tibetan Plateau was also demonstrated.
Y. L. Sun, Z. F. Wang, W. Du, Q. Zhang, Q. Q. Wang, P. Q. Fu, X. L. Pan, J. Li, J. Jayne, and D. R. Worsnop
Atmos. Chem. Phys., 15, 10149–10165, https://doi.org/10.5194/acp-15-10149-2015, https://doi.org/10.5194/acp-15-10149-2015, 2015
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We conducted the first long-term real-time measurement of submicron aerosol composition in Beijing using an ACSM for 1 year. The seasonal variations of mass concentrations and chemical composition of submicron aerosol were investigated in detail, and the meteorological effects on aerosol chemistry, particularly temperature and relative humidity, were elucidated. Finally, the potential source areas of aerosol species during four seasons were identified.
Y. R. Yang, X. G. Liu, Y. Qu, J. L. An, R. Jiang, Y. H. Zhang, Y. L. Sun, Z. J. Wu, F. Zhang, W. Q. Xu, and Q. X. Ma
Atmos. Chem. Phys., 15, 8165–8178, https://doi.org/10.5194/acp-15-8165-2015, https://doi.org/10.5194/acp-15-8165-2015, 2015
Q. Jiang, Y. L. Sun, Z. Wang, and Y. Yin
Atmos. Chem. Phys., 15, 6023–6034, https://doi.org/10.5194/acp-15-6023-2015, https://doi.org/10.5194/acp-15-6023-2015, 2015
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Aerosol composition and sources during the Chinese spring festival are characterized in detail. The roles of fireworks and secondary aerosol in fine particle pollution were elucidated. We observed large reductions of primary species, whereas changes of secondary aerosol during the holiday period were minor. This has significant implications; reducing primary emissions on a local scale during severe haze episodes might have a limited effect on improving air quality in megacities.
J. Z. Xu, Q. Zhang, Z. B. Wang, G. M. Yu, X. L. Ge, and X. Qin
Atmos. Chem. Phys., 15, 5069–5081, https://doi.org/10.5194/acp-15-5069-2015, https://doi.org/10.5194/acp-15-5069-2015, 2015
D. B. Atkinson, J. G. Radney, J. Lum, K. R. Kolesar, D. J. Cziczo, M. S. Pekour, Q. Zhang, A. Setyan, A. Zelenyuk, and C. D. Cappa
Atmos. Chem. Phys., 15, 4045–4061, https://doi.org/10.5194/acp-15-4045-2015, https://doi.org/10.5194/acp-15-4045-2015, 2015
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This work describes an analysis of measurements of the influence of water uptake on the light-scattering properties of sub- and supermicron-sized particles as observed in the Sacramento, CA, USA region during the 2010 CARES field campaign. The observations are used to derive campaign-average effective hygroscopicity parameters for submicron oxygenated organic aerosol and for supermicron particles, and the influence of chloride displacement reactions on particle hygroscopicity is examined.
Y. J. Zhang, L. L. Tang, Z. Wang, H. X. Yu, Y. L. Sun, D. Liu, W. Qin, F. Canonaco, A. S. H. Prévôt, H. L. Zhang, and H. C. Zhou
Atmos. Chem. Phys., 15, 1331–1349, https://doi.org/10.5194/acp-15-1331-2015, https://doi.org/10.5194/acp-15-1331-2015, 2015
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The chemical composition, sources, and evolution processes of PM1 were investigated with an Aerodyne ACSM during harvest seasons in the Yangtze River delta, China. Two biomass burning organic aerosol (BBOA) factors derived from PMF model were assessed. The oxidized BBOA contributes ~80% of the total BBOA loadings in the BB plumes. Evidence that BBOA may be oxidized to more aged and less volatile organics during the aging process was suggested.
L. Yu, J. Smith, A. Laskin, C. Anastasio, J. Laskin, and Q. Zhang
Atmos. Chem. Phys., 14, 13801–13816, https://doi.org/10.5194/acp-14-13801-2014, https://doi.org/10.5194/acp-14-13801-2014, 2014
J. Xu, Q. Zhang, M. Chen, X. Ge, J. Ren, and D. Qin
Atmos. Chem. Phys., 14, 12593–12611, https://doi.org/10.5194/acp-14-12593-2014, https://doi.org/10.5194/acp-14-12593-2014, 2014
K. Tsigaridis, N. Daskalakis, M. Kanakidou, P. J. Adams, P. Artaxo, R. Bahadur, Y. Balkanski, S. E. Bauer, N. Bellouin, A. Benedetti, T. Bergman, T. K. Berntsen, J. P. Beukes, H. Bian, K. S. Carslaw, M. Chin, G. Curci, T. Diehl, R. C. Easter, S. J. Ghan, S. L. Gong, A. Hodzic, C. R. Hoyle, T. Iversen, S. Jathar, J. L. Jimenez, J. W. Kaiser, A. Kirkevåg, D. Koch, H. Kokkola, Y. H Lee, G. Lin, X. Liu, G. Luo, X. Ma, G. W. Mann, N. Mihalopoulos, J.-J. Morcrette, J.-F. Müller, G. Myhre, S. Myriokefalitakis, N. L. Ng, D. O'Donnell, J. E. Penner, L. Pozzoli, K. J. Pringle, L. M. Russell, M. Schulz, J. Sciare, Ø. Seland, D. T. Shindell, S. Sillman, R. B. Skeie, D. Spracklen, T. Stavrakou, S. D. Steenrod, T. Takemura, P. Tiitta, S. Tilmes, H. Tost, T. van Noije, P. G. van Zyl, K. von Salzen, F. Yu, Z. Wang, Z. Wang, R. A. Zaveri, H. Zhang, K. Zhang, Q. Zhang, and X. Zhang
Atmos. Chem. Phys., 14, 10845–10895, https://doi.org/10.5194/acp-14-10845-2014, https://doi.org/10.5194/acp-14-10845-2014, 2014
J. D. Fast, J. Allan, R. Bahreini, J. Craven, L. Emmons, R. Ferrare, P. L. Hayes, A. Hodzic, J. Holloway, C. Hostetler, J. L. Jimenez, H. Jonsson, S. Liu, Y. Liu, A. Metcalf, A. Middlebrook, J. Nowak, M. Pekour, A. Perring, L. Russell, A. Sedlacek, J. Seinfeld, A. Setyan, J. Shilling, M. Shrivastava, S. Springston, C. Song, R. Subramanian, J. W. Taylor, V. Vinoj, Q. Yang, R. A. Zaveri, and Q. Zhang
Atmos. Chem. Phys., 14, 10013–10060, https://doi.org/10.5194/acp-14-10013-2014, https://doi.org/10.5194/acp-14-10013-2014, 2014
A. Setyan, C. Song, M. Merkel, W. B. Knighton, T. B. Onasch, M. R. Canagaratna, D. R. Worsnop, A. Wiedensohler, J. E. Shilling, and Q. Zhang
Atmos. Chem. Phys., 14, 6477–6494, https://doi.org/10.5194/acp-14-6477-2014, https://doi.org/10.5194/acp-14-6477-2014, 2014
C. Knote, A. Hodzic, J. L. Jimenez, R. Volkamer, J. J. Orlando, S. Baidar, J. Brioude, J. Fast, D. R. Gentner, A. H. Goldstein, P. L. Hayes, W. B. Knighton, H. Oetjen, A. Setyan, H. Stark, R. Thalman, G. Tyndall, R. Washenfelder, E. Waxman, and Q. Zhang
Atmos. Chem. Phys., 14, 6213–6239, https://doi.org/10.5194/acp-14-6213-2014, https://doi.org/10.5194/acp-14-6213-2014, 2014
F. Mei, A. Setyan, Q. Zhang, and J. Wang
Atmos. Chem. Phys., 13, 12155–12169, https://doi.org/10.5194/acp-13-12155-2013, https://doi.org/10.5194/acp-13-12155-2013, 2013
Y. L. Sun, Z. F. Wang, P. Q. Fu, T. Yang, Q. Jiang, H. B. Dong, J. Li, and J. J. Jia
Atmos. Chem. Phys., 13, 4577–4592, https://doi.org/10.5194/acp-13-4577-2013, https://doi.org/10.5194/acp-13-4577-2013, 2013
M. Gyawali, W. P. Arnott, R. A. Zaveri, C. Song, M. Pekour, B. Flowers, M. K. Dubey, A. Setyan, Q. Zhang, J. W. Harworth, J. G. Radney, D. B. Atkinson, S. China, C. Mazzoleni, K. Gorkowski, R. Subramanian, B. T. Jobson, and H. Moosmüller
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-7113-2013, https://doi.org/10.5194/acpd-13-7113-2013, 2013
Revised manuscript not accepted
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
The impact of traffic on air quality in Ireland: insights from the simultaneous kerbside and suburban monitoring of submicron aerosols
Vertical distribution of particle-phase dicarboxylic acids, oxoacids and α-dicarbonyls in the urban boundary layer based on the 325 m tower in Beijing
Characterization and source apportionment of aerosol light scattering in a typical polluted city in the Yangtze River Delta, China
Molecular insights into new particle formation in Barcelona, Spain
Tracking separate contributions of diesel and gasoline vehicles to roadside PM2.5 through online monitoring of volatile organic compounds and PM2.5 organic and elemental carbon: a 6-year study in Hong Kong
Probing key organic substances driving new particle growth initiated by iodine nucleation in coastal atmosphere
Variations in Ncn and Nccn over marginal seas in China related to marine traffic emissions, new particle formation and aerosol aging
Simultaneous measurements of urban and rural particles in Beijing – Part 1: Chemical composition and mixing state
Simultaneous measurements of urban and rural particles in Beijing – Part 2: Case studies of haze events and regional transport
Ship plumes in the Baltic Sea Sulfur Emission Control Area: chemical characterization and contribution to coastal aerosol concentrations
Contrasting sources and processes of particulate species in haze days with low and high relative humidity in wintertime Beijing
Overview: Integrative and Comprehensive Understanding on Polar Environments (iCUPE) – concept and initial results
Chemical characterization of secondary organic aerosol at a rural site in the southeastern US: insights from simultaneous high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and FIGAERO chemical ionization mass spectrometer (CIMS) measurements
Sea spray aerosol organic enrichment, water uptake and surface tension effects
A 1-year characterization of organic aerosol composition and sources using an extractive electrospray ionization time-of-flight mass spectrometer (EESI-TOF)
Decadal changes in anthropogenic source contribution of PM2.5 pollution and related health impacts in China, 1990–2015
Characterization of submicron particles by time-of-flight aerosol chemical speciation monitor (ToF-ACSM) during wintertime: aerosol composition, sources, and chemical processes in Guangzhou, China
Strong anthropogenic control of secondary organic aerosol formation from isoprene in Beijing
Synergistic enhancement of urban haze by nitrate uptake into transported hygroscopic particles in the Asian continental outflow
Long-term brown carbon and smoke tracer observations in Bogotá, Colombia: association with medium-range transport of biomass burning plumes
Importance of gas-particle partitioning of ammonia in haze formation in the rural agricultural environment
Resonance-enhanced detection of metals in aerosols using single-particle mass spectrometry
Measurement report: Characterization of severe spring haze episodes and influences of long-range transport in the Seoul metropolitan area in March 2019
Air mass physiochemical characteristics over New Delhi: impacts on aerosol hygroscopicity and cloud condensation nuclei (CCN) formation
Marine organic matter in the remote environment of the Cape Verde islands – an introduction and overview to the MarParCloud campaign
Molecular and spatial distributions of dicarboxylic acids, oxocarboxylic acids, and α-dicarbonyls in marine aerosols from the South China Sea to the eastern Indian Ocean
Molecular characterization of firework-related urban aerosols using Fourier transform ion cyclotron resonance mass spectrometry
Measurement report: Vertical distribution of atmospheric particulate matter within the urban boundary layer in southern China – size-segregated chemical composition and secondary formation through cloud processing and heterogeneous reactions
Mixing states of Amazon-basin aerosol particles transported over long distances using transmission electron microscopy
Hygroscopicity of urban aerosols and its link to size-resolved chemical composition during spring/summertime in Seoul, Korea
Direct links between hygroscopicity and mixing state of ambient aerosols: estimating particle hygroscopicity from their single-particle mass spectra
Investigation of the wet removal rate of black carbon in East Asia: validation of a below- and in-cloud wet removal scheme in FLEXPART v10.4
Characterization of carbonaceous aerosols in Singapore: insight from black carbon fragments and trace metal ions detected by a soot particle aerosol mass spectrometer
Contribution of hydroxymethanesulfonate (HMS) to severe winter haze in the North China Plain
Size segregated particle number and mass emissions in urban Beijing
Characteristics of methanesulfonic acid, non-sea-salt sulfate and organic carbon aerosols over the Amundsen Sea, Antarctica
Exploring wintertime regional haze in northeast China: role of coal and biomass burning
Transformation and ageing of biomass burning carbonaceous aerosol over tropical South America from aircraft in situ measurements during SAMBBA
Physico-chemical characterization of urban aerosols from specific combustion sources in West Africa at Abidjan in Côte d'Ivoire and Cotonou in Benin in the frame of the DACCIWA program
Characterization and comparison of PM2.5 oxidative potential assessed by two acellular assays
Characterization of the light-absorbing properties, chromophore composition and sources of brown carbon aerosol in Xi'an, northwestern China
Nitrate-dominated PM2.5 and elevation of particle pH observed in urban Beijing during the winter of 2017
Tracer-based investigation of organic aerosols in marine atmospheres from marginal seas of China to the northwest Pacific Ocean
Optical properties and molecular compositions of water-soluble and water-insoluble brown carbon (BrC) aerosols in northwest China
Influence of vessel characteristics and atmospheric processes on the gas and particle phase of ship emission plumes: in situ measurements in the Mediterranean Sea and around the Arabian Peninsula
Seasonal source variability of carbonaceous aerosols at the Rwanda Climate Observatory
Formation and sink of glyoxal and methylglyoxal in a polluted subtropical environment: observation-based photochemical analysis and impact evaluation
Fossil fuel combustion, biomass burning and biogenic sources of fine carbonaceous aerosol in the Carpathian Basin
Shipborne measurements of Antarctic submicron organic aerosols: an NMR perspective linking multiple sources and bioregions
Formation mechanisms of atmospheric nitrate and sulfate during the winter haze pollution periods in Beijing: gas-phase, heterogeneous and aqueous-phase chemistry
Chunshui Lin, Darius Ceburnis, Wei Xu, Eimear Heffernan, Stig Hellebust, John Gallagher, Ru-Jin Huang, Colin O'Dowd, and Jurgita Ovadnevaite
Atmos. Chem. Phys., 20, 10513–10529, https://doi.org/10.5194/acp-20-10513-2020, https://doi.org/10.5194/acp-20-10513-2020, 2020
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Chemical composition and sources of submicron aerosols (PM1) were simultaneously investigated at a kerbside site in the Dublin city center and at a residential site in suburban Dublin (~5 km apart) during both a nonheating and a heating period in 2018. This study highlights the temporal and spatial variability of sources within the Dublin city center and the need for additional aerosol characterization studies to improve targeted mitigation solutions for a greater impact on urban air quality.
Wanyu Zhao, Hong Ren, Kimitaka Kawamura, Huiyun Du, Xueshun Chen, Siyao Yue, Qiaorong Xie, Lianfang Wei, Ping Li, Xin Zeng, Shaofei Kong, Yele Sun, Zifa Wang, and Pingqing Fu
Atmos. Chem. Phys., 20, 10331–10350, https://doi.org/10.5194/acp-20-10331-2020, https://doi.org/10.5194/acp-20-10331-2020, 2020
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Our observations provide detailed information on the abundance and vertical distribution of dicarboxylic acids, oxoacids and α-dicarbonyls in PM2.5 collected at three heights based on a 325 m meteorological tower in Beijing in summer. Our results demonstrate that organic acids at the ground surface are largely associated with local traffic emissions, while long-range atmospheric transport followed by photochemical ageing contributes more in the urban boundary layer than the ground surface.
Dong Chen, Yu Zhao, Jie Zhang, Huan Yu, and Xingna Yu
Atmos. Chem. Phys., 20, 10193–10210, https://doi.org/10.5194/acp-20-10193-2020, https://doi.org/10.5194/acp-20-10193-2020, 2020
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We studied the characteristics and sources of aerosol scattering for Nanjing. The method of aerosol scattering estimation was optimized based on field measurements, and the impacts of aerosol size and composition were quantified. To explore the reasons for the reduced visibility, source apportionment of aerosol scattering was conducted by pollution level. This work stressed the linkage between aerosols and visibility and improved the understanding of emissions and their role in air quality.
James Brean, David C. S. Beddows, Zongbo Shi, Brice Temime-Roussel, Nicolas Marchand, Xavier Querol, Andrés Alastuey, María Cruz Minguillón, and Roy M. Harrison
Atmos. Chem. Phys., 20, 10029–10045, https://doi.org/10.5194/acp-20-10029-2020, https://doi.org/10.5194/acp-20-10029-2020, 2020
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New particle formation is a key process influencing both local air quality and climatically active cloud condensation nuclei concentrations. This study has carried out fundamental measurements of nucleation processes in Barcelona, Spain, and concludes that a mechanism involving stabilisation of sulfuric acid clusters by low molecular weight amines is primarily responsible for new particle formation events.
Yee Ka Wong, X. H. Hilda Huang, Peter K. K. Louie, Alfred L. C. Yu, Damgy H. L. Chan, and Jian Zhen Yu
Atmos. Chem. Phys., 20, 9871–9882, https://doi.org/10.5194/acp-20-9871-2020, https://doi.org/10.5194/acp-20-9871-2020, 2020
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We present an approach to track separate contributions to PM2.5 by gasoline and diesel vehicles through a positive matrix factorization analysis of online monitoring data measurable by relatively inexpensive analytical instruments. They are PM2.5 organic and elemental carbon, C2–C9 volatile organic compounds, and nitrogen oxide concentrations. The method was demonstrated to be effective by applying monitoring data spanning 6 years (2011–2017) from a roadside environment in Hong Kong.
Yibei Wan, Xiangpeng Huang, Bin Jiang, Binyu Kuang, Manfei Lin, Deming Xia, Yuhong Liao, Jingwen Chen, Jian Zhen Yu, and Huan Yu
Atmos. Chem. Phys., 20, 9821–9835, https://doi.org/10.5194/acp-20-9821-2020, https://doi.org/10.5194/acp-20-9821-2020, 2020
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Biogenic iodine emission from macroalgae and microalgae could initiate atmospheric new particle formation (NPF). But it is unknown if other species are needed to drive the growth of new iodine particles in the marine boundary layer. Unlike the deeper understanding of organic compounds driving continental NPF, little is known about the organics involved in coastal or open-ocean NPF. This article reveals a new group of important organic compounds involved in this process.
Yang Gao, Deqiang Zhang, Juntao Wang, Huiwang Gao, and Xiaohong Yao
Atmos. Chem. Phys., 20, 9665–9677, https://doi.org/10.5194/acp-20-9665-2020, https://doi.org/10.5194/acp-20-9665-2020, 2020
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Through the cruise campaign conducted over marginal seas in China, we found that the concentrations of condensation nuclei (Ncn) and cloud condensation nuclei (Nccn) were 1 order of magnitude larger than those in remote clear marine atmospheres, indicating overwhelming contributions from marine traffic emissions and long-range continental transport. Moreover, we derived regression equations used to estimate Ncn and Nccn from SO2 when the direct observations of Ncn and Nccn are not available.
Yang Chen, Jing Cai, Zhichao Wang, Chao Peng, Xiaojiang Yao, Mi Tian, Yiqun Han, Guangming Shi, Zongbo Shi, Yue Liu, Xi Yang, Mei Zheng, Tong Zhu, Kebin He, Qiang Zhang, and Fumo Yang
Atmos. Chem. Phys., 20, 9231–9247, https://doi.org/10.5194/acp-20-9231-2020, https://doi.org/10.5194/acp-20-9231-2020, 2020
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Patterns of particle transport, accumulation, and evolution in both urban and rural areas of Beijing are investigated. The two sites shared 17 common particle types in different stages of atmospheric processing.
Yang Chen, Guangming Shi, Jing Cai, Zongbo Shi, Zhichao Wang, Xiaojiang Yao, Mi Tian, Chao Peng, Yiqun Han, Tong Zhu, Yue Liu, Xi Yang, Mei Zheng, Fumo Yang, Qiang Zhang, and Kebin He
Atmos. Chem. Phys., 20, 9249–9263, https://doi.org/10.5194/acp-20-9249-2020, https://doi.org/10.5194/acp-20-9249-2020, 2020
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Individual particles were observed in two field studies during winter 2016 in the urban and rural areas of Beijing. An online single-particle chemical composition analysis was used as a tracing system to investigate the impact of heating activities and the formation of haze events. During the pollution events, a pattern of transport and accumulation was found with evidence of single particles. The transport from Pinggu to Peking University was significant but PKU to PG occurred occasionally.
Stina Ausmeel, Axel Eriksson, Erik Ahlberg, Moa K. Sporre, Mårten Spanne, and Adam Kristensson
Atmos. Chem. Phys., 20, 9135–9151, https://doi.org/10.5194/acp-20-9135-2020, https://doi.org/10.5194/acp-20-9135-2020, 2020
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Emissions from shipping have an impact on air quality, especially in coastal areas. We have measured properties of the airborne particles in several plumes from ships that are sailing within an Emission Control Area. Individual ships showed large variability in contribution to total particle mass and nitrogen dioxide. Organics and sulfate dominated the particle mass, and most plumes contained very little or no soot. We also present recommendations for future stationary ship plume measurements.
Ru-Jin Huang, Yao He, Jing Duan, Yongjie Li, Qi Chen, Yan Zheng, Yang Chen, Weiwei Hu, Chunshui Lin, Haiyan Ni, Wenting Dai, Junji Cao, Yunfei Wu, Renjian Zhang, Wei Xu, Jurgita Ovadnevaite, Darius Ceburnis, Thorsten Hoffmann, and Colin D. O'Dowd
Atmos. Chem. Phys., 20, 9101–9114, https://doi.org/10.5194/acp-20-9101-2020, https://doi.org/10.5194/acp-20-9101-2020, 2020
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We systematically compared the submicron particle (PM1) processes in haze days with low and high relative humidity (RH) in wintertime Beijing. Nitrate had similar daytime growth rates in low-RH and high-RH pollution. OOA had a higher growth rate in low-RH pollution than in high-RH pollution. Sulfate had a decreasing trend in low-RH pollution, while it increased significantly in high-RH pollution. This distinction may be explained by the different processes affected by meteorological conditions.
Tuukka Petäjä, Ella-Maria Duplissy, Ksenia Tabakova, Julia Schmale, Barbara Altstädter, Gerard Ancellet, Mikhail Arshinov, Yurii Balin, Urs Baltensperger, Jens Bange, Alison Beamish, Boris Belan, Antoine Berchet, Rossana Bossi, Warren R. L. Cairns, Ralf Ebinghaus, Imad El Haddad, Beatriz Ferreira-Araujo, Anna Franck, Lin Huang, Antti Hyvärinen, Angelika Humbert, Athina-Cerise Kalogridis, Pavel Konstantinov, Astrid Lampert, Matthew MacLeod, Olivier Magand, Alexander Mahura, Louis Marelle, Vladimir Masloboev, Dmitri Moisseev, Vaios Moschos, Niklas Neckel, Tatsuo Onishi, Stefan Osterwalder, Aino Ovaska, Pauli Paasonen, Mikhail Panchenko, Fidel Pankratov, Jakob B. Pernov, Andreas Platis, Olga Popovicheva, Jean-Christophe Raut, Aurélie Riandet, Torsten Sachs, Rosamaria Salvatori, Roberto Salzano, Ludwig Schröder, Martin Schön, Vladimir Shevchenko, Henrik Skov, Jeroen E. Sonke, Andrea Spolaor, Vasileios K. Stathopoulos, Mikko Strahlendorff, Jennie L. Thomas, Vito Vitale, Sterios Vratolis, Carlo Barbante, Sabine Chabrillat, Aurélien Dommergue, Konstantinos Eleftheriadis, Jyri Heilimo, Kathy S. Law, Andreas Massling, Steffen M. Noe, Jean-Daniel Paris, André S. H. Prévôt, Ilona Riipinen, Birgit Wehner, Zhiyong Xie, and Hanna K. Lappalainen
Atmos. Chem. Phys., 20, 8551–8592, https://doi.org/10.5194/acp-20-8551-2020, https://doi.org/10.5194/acp-20-8551-2020, 2020
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The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. Here we summarize initial results from our integrative project exploring the Arctic environment and pollution to deliver data products, metrics, and indicators for stakeholders.
Yunle Chen, Masayuki Takeuchi, Theodora Nah, Lu Xu, Manjula R. Canagaratna, Harald Stark, Karsten Baumann, Francesco Canonaco, André S. H. Prévôt, L. Gregory Huey, Rodney J. Weber, and Nga L. Ng
Atmos. Chem. Phys., 20, 8421–8440, https://doi.org/10.5194/acp-20-8421-2020, https://doi.org/10.5194/acp-20-8421-2020, 2020
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Two online mass spectrometry instruments, an aerosol mass spectrometer and a chemical ionization mass spectrometer equipped with a filter inlet for gases and aerosols, were deployed at Yorkville, GA, for a comprehensive characterization of organic aerosol. We observed notable secondary organic aerosol formation from isoprene and monoterpenes via different pathways during both day and night, and a series of highly oxidized acid-like compounds was found to be closely related to aged SOA.
Luke T. Cravigan, Marc D. Mallet, Petri Vaattovaara, Mike J. Harvey, Cliff S. Law, Robin L. Modini, Lynn M. Russell, Ed Stelcer, David D. Cohen, Greg Olsen, Karl Safi, Timothy J. Burrell, and Zoran Ristovski
Atmos. Chem. Phys., 20, 7955–7977, https://doi.org/10.5194/acp-20-7955-2020, https://doi.org/10.5194/acp-20-7955-2020, 2020
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Aerosol–cloud interactions in remote marine environments are poorly represented in atmospheric modelling, particularly over the Southern Hemisphere. This work reports in situ chamber observations of sea spray aerosol composition and water uptake during the Surface Ocean Aerosol Production (SOAP) voyage. Observations were compared with currently applied models for sea spray organic enrichment. The sea spray hygroscopicity was persistently high, even at high organic fractions.
Lu Qi, Alexander L. Vogel, Sepideh Esmaeilirad, Liming Cao, Jing Zheng, Jean-Luc Jaffrezo, Paola Fermo, Anne Kasper-Giebl, Kaspar R. Daellenbach, Mindong Chen, Xinlei Ge, Urs Baltensperger, André S. H. Prévôt, and Jay G. Slowik
Atmos. Chem. Phys., 20, 7875–7893, https://doi.org/10.5194/acp-20-7875-2020, https://doi.org/10.5194/acp-20-7875-2020, 2020
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We present the first application of this online and offline strategy using the new extractive electrospray ionization time-of-flight mass spectrometer (EESI-TOF), which achieves increased chemical specificity relative to other online techniques. Measurement and source apportionment of 1 year of filter samples collected in Zurich, Switzerland, show seasonal contributions from fresh and aged wood combustion in winter and biogenic emission-derived SOA in summer, as well as other sources.
Jun Liu, Yixuan Zheng, Guannan Geng, Chaopeng Hong, Meng Li, Xin Li, Fei Liu, Dan Tong, Ruili Wu, Bo Zheng, Kebin He, and Qiang Zhang
Atmos. Chem. Phys., 20, 7783–7799, https://doi.org/10.5194/acp-20-7783-2020, https://doi.org/10.5194/acp-20-7783-2020, 2020
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Ambient PM2.5 pollution contributed substantially to premature mortality in China. The contributions of various sectors to anthropogenic PM2.5-related premature mortality have changed substantially during 1990–2015. In 1990, the residential sector was the leading source, followed by industry, power, agriculture, and transportation, whereas in 2015, the industrial sector became the largest contributor, followed by the residential sector, agriculture, transportation, and power.
Junchen Guo, Shengzhen Zhou, Mingfu Cai, Jun Zhao, Wei Song, Weixiong Zhao, Weiwei Hu, Yele Sun, Yao He, Chengqiang Yang, Xuezhe Xu, Zhisheng Zhang, Peng Cheng, Qi Fan, Jian Hang, Shaojia Fan, Xinming Wang, and Xuemei Wang
Atmos. Chem. Phys., 20, 7595–7615, https://doi.org/10.5194/acp-20-7595-2020, https://doi.org/10.5194/acp-20-7595-2020, 2020
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We characterized non-refractory submicron particulate matter (PM1.0) during winter in Guangzhou, south China. Chemical composition and key sources of ambient PM1.0 are revealed, highlighting the significant role of SOA. The relationship with SOA and peroxy radicals indicated gas-phase oxidation contributed predominantly to SOA formation during non-pollution periods, while heterogeneous/multiphase reactions played more important roles in SOA formation during pollution periods.
Daniel J. Bryant, William J. Dixon, James R. Hopkins, Rachel E. Dunmore, Kelly L. Pereira, Marvin Shaw, Freya A. Squires, Thomas J. Bannan, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Bin Ouyang, Tianqu Cui, Jason D. Surratt, Di Liu, Zongbo Shi, Roy Harrison, Yele Sun, Weiqi Xu, Alastair C. Lewis, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 20, 7531–7552, https://doi.org/10.5194/acp-20-7531-2020, https://doi.org/10.5194/acp-20-7531-2020, 2020
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Using the chemical composition of offline filter samples, we report that a large share of oxidized organic aerosol in Beijing during summer is due to isoprene secondary organic aerosol (iSOA). iSOA organosulfates showed a strong correlation with the product of ozone and particulate sulfate. This highlights the role of both photochemistry and the availability of particulate sulfate in heterogeneous reactions and further demonstrates that iSOA formation is controlled by anthropogenic emissions.
Jihoon Seo, Yong Bin Lim, Daeok Youn, Jin Young Kim, and Hyoun Cher Jin
Atmos. Chem. Phys., 20, 7575–7594, https://doi.org/10.5194/acp-20-7575-2020, https://doi.org/10.5194/acp-20-7575-2020, 2020
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This study investigates the synergistic role of transported regional haze in increasing local inorganic aerosols. PM2.5 data measured at Seoul, South Korea, together with a thermodynamic model show that the transported haze particles from the polluted continent are richer in inorganics and wetter than the local haze particles. The transported wet particles readily increase the inorganic aerosols through the uptake of HNO3 in NOx- and NH3-rich urban environments like Seoul.
Juan Manuel Rincón-Riveros, Maria Alejandra Rincón-Caro, Amy P. Sullivan, Juan Felipe Mendez-Espinosa, Luis Carlos Belalcazar, Miguel Quirama Aguilar, and Ricardo Morales Betancourt
Atmos. Chem. Phys., 20, 7459–7472, https://doi.org/10.5194/acp-20-7459-2020, https://doi.org/10.5194/acp-20-7459-2020, 2020
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Air pollution affects health for millions of people worldwide. This is particularly worrisome for citizens in emerging economies where air quality is often heavily deteriorated. We show how, every year, agricultural burns and forest fires in the grasslands of northern South America increase the concentration of harmful particles in the environment, further worsening air quality for nearly 60 million in this region, even when the fires occur hundreds of kilometers away from urban areas.
Jian Xu, Jia Chen, Na Zhao, Guochen Wang, Guangyuan Yu, Hao Li, Juntao Huo, Yanfen Lin, Qingyan Fu, Hongyu Guo, Congrui Deng, Shan-Hu Lee, Jianmin Chen, and Kan Huang
Atmos. Chem. Phys., 20, 7259–7269, https://doi.org/10.5194/acp-20-7259-2020, https://doi.org/10.5194/acp-20-7259-2020, 2020
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This study provided evidence that gas-particle partitioning of ammonia, as opposed to ammonia concentration, plays a critical role in the haze formation. A reduction in ammonia emissions alone may not reduce air pollution effectively, at least at rural agricultural sites in China.
Johannes Passig, Julian Schade, Ellen Iva Rosewig, Robert Irsig, Thomas Kröger-Badge, Hendryk Czech, Martin Sklorz, Thorsten Streibel, Lei Li, Xue Li, Zhen Zhou, Henrik Fallgren, Jana Moldanova, and Ralf Zimmermann
Atmos. Chem. Phys., 20, 7139–7152, https://doi.org/10.5194/acp-20-7139-2020, https://doi.org/10.5194/acp-20-7139-2020, 2020
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Particle-bound metals in both natural dusts and polluted air can induce severe health effects. They are also transported by the wind into the oceans; provide micronutrients; and thus modulate biodiversity, fisheries, and climate. We show a way to more efficiently detect metals in individual particles while preserving source information. Our detection scheme is less dependent on the particle type and atmospheric changes and is thus valuable to the study of biogechemical cycles and air pollution.
Hwajin Kim, Qi Zhang, and Yele Sun
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-382, https://doi.org/10.5194/acp-2020-382, 2020
Revised manuscript accepted for ACP
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Severe spring haze and influences of long-range transport in the Seoul metropolitan area in March 2019 was investigated. Simultaneous downwind (SMA) and upwind (Beijing) measurements using AMS and ACSM over the same period showed that the PM species can be transported approximately in two days. Nitrate was the most responsible and sulfate and two regional transport influenced SOAs also contributed. Enhancement of Pb also showed that the haze in SMA was influenced by the regional transport.
Zainab Arub, Sahil Bhandari, Shahzad Gani, Joshua S. Apte, Lea Hildebrandt Ruiz, and Gazala Habib
Atmos. Chem. Phys., 20, 6953–6971, https://doi.org/10.5194/acp-20-6953-2020, https://doi.org/10.5194/acp-20-6953-2020, 2020
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Aerosol physiochemical properties were characterized for three prominent air masses over New Delhi, a highly polluted megacity. The chemical composition and size distribution data were used to deduce the hygroscopicity parameter and cloud condensation nuclei (CCN) number concentration. The activated fraction was the highest in the world for any continental site. The aerosol physiochemical properties and their diurnal patterns were interlinked and impacted aerosol hygroscopicity and CCN activity.
Manuela van Pinxteren, Khanneh Wadinga Fomba, Nadja Triesch, Christian Stolle, Oliver Wurl, Enno Bahlmann, Xianda Gong, Jens Voigtländer, Heike Wex, Tiera-Brandy Robinson, Stefan Barthel, Sebastian Zeppenfeld, Erik Hans Hoffmann, Marie Roveretto, Chunlin Li, Benoit Grosselin, Veronique Daële, Fabian Senf, Dominik van Pinxteren, Malena Manzi, Nicolás Zabalegui, Sanja Frka, Blaženka Gašparović, Ryan Pereira, Tao Li, Liang Wen, Jiarong Li, Chao Zhu, Hui Chen, Jianmin Chen, Björn Fiedler, Wolf von Tümpling, Katie Alana Read, Shalini Punjabi, Alastair Charles Lewis, James Roland Hopkins, Lucy Jane Carpenter, Ilka Peeken, Tim Rixen, Detlef Schulz-Bull, María Eugenia Monge, Abdelwahid Mellouki, Christian George, Frank Stratmann, and Hartmut Herrmann
Atmos. Chem. Phys., 20, 6921–6951, https://doi.org/10.5194/acp-20-6921-2020, https://doi.org/10.5194/acp-20-6921-2020, 2020
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An introduction to a comprehensive field campaign performed at the Cape Verde Atmospheric Observatory regarding ocean–atmosphere interactions is given. Chemical, physical, biological and meteorological techniques were applied, and measurements of bulk water, the sea surface microlayer, cloud water and ambient aerosol particles took place. Oceanic compounds were found to be transferred to atmospheric aerosol and to the cloud level; however, sea spray contributions to CCN and INPs were limited.
Jing Yang, Wanyu Zhao, Lianfang Wei, Qiang Zhang, Yue Zhao, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Xiaole Pan, Yele Sun, Zifa Wang, Cong-Qiang Liu, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 20, 6841–6860, https://doi.org/10.5194/acp-20-6841-2020, https://doi.org/10.5194/acp-20-6841-2020, 2020
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Our observations provide novel detailed information on the atmospheric abundances and spatial distributions of dicarboxylic acids, oxoacids, and α-dicarbonyls in marine aerosols collected from the South China Sea to the East Indian Ocean. Our results demonstrate that the continental outflow of both biogenic and anthropogenic precursors followed by photochemical aging is one of the main sources and formation processes of marine organic aerosols over the tropical oceanic regions.
Qiaorong Xie, Sihui Su, Shuang Chen, Yisheng Xu, Dong Cao, Jing Chen, Lujie Ren, Siyao Yue, Wanyu Zhao, Yele Sun, Zifa Wang, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, Guibin Jiang, Cong-Qiang Liu, and Pingqing Fu
Atmos. Chem. Phys., 20, 6803–6820, https://doi.org/10.5194/acp-20-6803-2020, https://doi.org/10.5194/acp-20-6803-2020, 2020
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Current knowledge on firework-related organic aerosols is very limited. Here the detailed molecular composition of organics in urban aerosols was characterized using ultrahigh-resolution FT-ICR mass spectrometry. Our findings highlight that firework emission leads to a sharp increase in CHO, CHNO, and CHOS containing high-molecular-weight species, particularly aromatic-like substances, which affect the physicochemical properties such as the light absorption and health effects of urban aerosols.
Shengzhen Zhou, Luolin Wu, Junchen Guo, Weihua Chen, Xuemei Wang, Jun Zhao, Yafang Cheng, Zuzhao Huang, Jinpu Zhang, Yele Sun, Pingqing Fu, Shiguo Jia, Jun Tao, Yanning Chen, and Junxia Kuang
Atmos. Chem. Phys., 20, 6435–6453, https://doi.org/10.5194/acp-20-6435-2020, https://doi.org/10.5194/acp-20-6435-2020, 2020
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In this work, measurements of size-segregated aerosols were conducted at three altitudes (ground level, 118 m, and 488 m) on the 610 m high Canton Tower in southern China. Vertical variations of PM and size-segregated chemical compositions were investigated. The results indicated that meteorological parameters and atmospheric aqueous and heterogeneous reactions together led to aerosol formation and haze episodes in the Pearl River Delta region during the measurement periods.
Kouji Adachi, Naga Oshima, Zhaoheng Gong, Suzane de Sá, Adam P. Bateman, Scot T. Martin, Joel F. de Brito, Paulo Artaxo, Glauber G. Cirino, Arthur J. Sedlacek III, and Peter R. Buseck
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-452, https://doi.org/10.5194/acp-2020-452, 2020
Revised manuscript accepted for ACP
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Occurrences, size distributions, and number fractions of individual aerosol particles from the Amazon basin during the GoAmazon2014/5 campaign were analyzed using transmission electron microscopy. Aerosol particles from natural sources (e.g., mineral dust, primary biological aerosols, and sea salts) during the wet season originated from the Amazon forest and long-range transports (the Saharan desert and the Atlantic Ocean). They commonly mix at an individual particle scale during transport.
Najin Kim, Seong Soo Yum, Minsu Park, Jong Sung Park, Hye Jung Shin, and Joon Young Ahn
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-450, https://doi.org/10.5194/acp-2020-450, 2020
Revised manuscript accepted for ACP
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Chemical effects on the size-resolved hygroscopicity of urban aerosols were examined based on the KORUS-AQ field campaign data (HTDMA and HR-ToF-AMS). The size-resolved chemical composition data were found to be critical in explaining the size-dependent hygroscopicity as well as the diurnal variation of κ for small particles. Aerosol mixing state information was associated with the size-resolved chemical composition data to reveal chemical information of different hygroscopicity modes.
Xinning Wang, Xingnan Ye, Jianmin Chen, Xiaofei Wang, Xin Yang, Tzung-May Fu, Lei Zhu, and Chongxuan Liu
Atmos. Chem. Phys., 20, 6273–6290, https://doi.org/10.5194/acp-20-6273-2020, https://doi.org/10.5194/acp-20-6273-2020, 2020
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Hygroscopicity plays several key roles in determining aerosol optical properties and aging processes in the atmosphere. However, it is quite difficult to study aerosol hygroscopicity at the single-particle level. In this study, we built a comprehensive database linking hygroscopicities and mass spectra of individual particles. Based on the measured hygroscopicity–composition relations, we developed a statistical method to estimate ambient particle hygroscopicity just from their mass spectra.
Yongjoo Choi, Yugo Kanaya, Masayuki Takigawa, Chunmao Zhu, Seung-Myung Park, Atsushi Matsuki, Yasuhiro Sadanaga, Sang-Woo Kim, Xiaole Pan, and Ignacio Pisso
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-402, https://doi.org/10.5194/acp-2020-402, 2020
Revised manuscript accepted for ACP
Laura-Hélèna Rivellini, Max Gerrit Adam, Nethmi Kasthuriarachchi, and Alex King Yin Lee
Atmos. Chem. Phys., 20, 5977–5993, https://doi.org/10.5194/acp-20-5977-2020, https://doi.org/10.5194/acp-20-5977-2020, 2020
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This work highlights that trace metals and refractory black carbon (rBC), and their inclusion in a source–receptor model, can provide important insight into the source apportionment of carbonaceous aerosols. In Singapore, we evidenced that 90 % of rBC originated from traffic/industrial emissions. The association of aged OA with K and Rb underlines the influence of regional biomass burning sources, while rBC fragmentation patterns and V/Ni were used to identify industrial and shipping pollutants.
Tao Ma, Hiroshi Furutani, Fengkui Duan, Takashi Kimoto, Jingkun Jiang, Qiang Zhang, Xiaobin Xu, Ying Wang, Jian Gao, Guannan Geng, Meng Li, Shaojie Song, Yongliang Ma, Fei Che, Jie Wang, Lidan Zhu, Tao Huang, Michisato Toyoda, and Kebin He
Atmos. Chem. Phys., 20, 5887–5897, https://doi.org/10.5194/acp-20-5887-2020, https://doi.org/10.5194/acp-20-5887-2020, 2020
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The formation mechanisms of organic matter and sulfate in winter haze in the North China Plain remain unclear. This paper presents the identification and quantification of hydroxymethanesulfonate (HMS) in PM2.5 in Beijing winter and elucidates the heterogeneous HMS chemistry in favorable winter haze conditions. We show that the HMS not only contributes a substantial mass of organic matter, but also leads to an overestimation of sulfate in conventional measurements.
Jing Cai, Biwu Chu, Lei Yao, Chao Yan, Liine M. Heikkinen, Feixue Zheng, Chang Li, Xiaolong Fan, Shaojun Zhang, Daoyuan Yang, Yonghong Wang, Tom V. Kokkonen, Tommy Chan, Ying Zhou, Lubna Dada, Yongchun Liu, Hong He, Pauli Paasonen, Joni T. Kujansuu, Tuukka Petäjä, Claudia Mohr, Juha Kangasluoma, Federico Bianchi, Yele Sun, Philip L. Croteau, Douglas R. Worsnop, Veli-Matti Kerminen, Wei Du, Markku Kulmala, and Kaspar R. Daellenbach
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-248, https://doi.org/10.5194/acp-2020-248, 2020
Revised manuscript accepted for ACP
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By applying both OA-PMF and Size-PMF at the same urban measurement site in Beijing, similar particle source-types, including vehicular emissions, cooking emissions and secondary formation-related sources were resolved by both frameworks and agreed well. It is also found that in the absence of new-particle formation, vehicular and cooking emissions dominate the particle number concentration while secondary particulate matter governed PM2.5 mass during spring and summer in Beijing.
Jinyoung Jung, Sang-Bum Hong, Meilian Chen, Jin Hur, Liping Jiao, Youngju Lee, Keyhong Park, Doshik Hahm, Jung-Ok Choi, Eun Jin Yang, Jisoo Park, Tae-Wan Kim, and SangHoon Lee
Atmos. Chem. Phys., 20, 5405–5424, https://doi.org/10.5194/acp-20-5405-2020, https://doi.org/10.5194/acp-20-5405-2020, 2020
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Characteristics of atmospheric sulfur and organic carbon species in marine aerosols and the environmental factors influencing their distributions were investigated over the Southern Ocean and the Amundsen Sea, Antarctica, during austral summer. The simultaneous measurements of chemical species in aerosols as well as the chemical and biological properties of seawater in the Amundsen Sea allowed for a better understanding of the effect of the ocean ecosystem on marine aerosols.
Jian Zhang, Lei Liu, Liang Xu, Qiuhan Lin, Hujia Zhao, Zhibin Wang, Song Guo, Min Hu, Dantong Liu, Zongbo Shi, Dao Huang, and Weijun Li
Atmos. Chem. Phys., 20, 5355–5372, https://doi.org/10.5194/acp-20-5355-2020, https://doi.org/10.5194/acp-20-5355-2020, 2020
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Northeast China faces severe air pollution in regional haze in wintertime. In this study, we revealed a contrasting formation mechanism of two typical haze events: Haze-I was induced by adverse meteorological conditions together with residential coal burning emissions; Haze-II was caused by agricultural biomass waste burning. In particular, we observed large numbers of tar balls as the primary brown carbon in northeast China.
William T. Morgan, James D. Allan, Stéphane Bauguitte, Eoghan Darbyshire, Michael J. Flynn, James Lee, Dantong Liu, Ben Johnson, Jim Haywood, Karla M. Longo, Paulo E. Artaxo, and Hugh Coe
Atmos. Chem. Phys., 20, 5309–5326, https://doi.org/10.5194/acp-20-5309-2020, https://doi.org/10.5194/acp-20-5309-2020, 2020
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We flew a large atmospheric research aircraft across a number of different environments in the Amazon basin during the 2012 biomass burning season. Smoke from fires builds up and has a significant impact on weather, climate, health and natural ecosystems. Our goal was to quantify changes in the properties of the smoke emitted by fires as it is transported through the atmosphere. We found that the major control on the properties of the smoke was due to differences in the fires themselves.
Aka Jacques Adon, Catherine Liousse, Elhadji Thierno Doumbia, Armelle Baeza-Squiban, Hélène Cachier, Jean-Francois Léon, Véronique Yoboué, Aristique Barthel Akpo, Corinne Galy-Lacaux, Benjamin Guinot, Cyril Zouiten, Hongmei Xu, Eric Gardrat, and Sekou Keita
Atmos. Chem. Phys., 20, 5327–5354, https://doi.org/10.5194/acp-20-5327-2020, https://doi.org/10.5194/acp-20-5327-2020, 2020
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It is our responsibility to establish a link between emissions, air pollution, and health impacts for urban combustion sources, typical of Africa.
Our results show that the particulate concentrations observed at all sites far exceed the recommendations of WHO. The site influenced by domestic fires is the most polluted site, dominated by a significant fraction of ultrafine particles. These studies will eventually lead to the implementation of emission reduction solutions to improve air quality.
Dong Gao, Krystal J. Godri Pollitt, James A. Mulholland, Armistead G. Russell, and Rodney J. Weber
Atmos. Chem. Phys., 20, 5197–5210, https://doi.org/10.5194/acp-20-5197-2020, https://doi.org/10.5194/acp-20-5197-2020, 2020
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This study provides a direct intercomparison between two assays for quantifying oxidative potential (OP) of ambient particles: the synthetic respiratory-tract-lining fluid (RTLF) assay and the dithiothreitol (DTT) assay. The results suggest that the DTT assay and the ascorbic acid depletion in RTLF are associated with organic species, transition metal ions, and antagonistic interactions between species. The glutathione depletion in RTLF is strongly dependent on water-soluble copper.
Wei Yuan, Ru-Jin Huang, Lu Yang, Jie Guo, Ziyi Chen, Jing Duan, Ting Wang, Haiyan Ni, Yongming Han, Yongjie Li, Qi Chen, Yang Chen, Thorsten Hoffmann, and Colin O'Dowd
Atmos. Chem. Phys., 20, 5129–5144, https://doi.org/10.5194/acp-20-5129-2020, https://doi.org/10.5194/acp-20-5129-2020, 2020
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We characterized light-absorbing properties, chromophore composition and sources of brown carbon (BrC) in Xi'an; identified three groups of light-absorbing organics; and quantified their contribution to overall BrC absorption. Our results showed that vehicle emissions and secondary formation are major sources of BrC in spring, coal combustion and vehicle emissions are major sources in fall, biomass burning and coal combustion become major sources in winter, and secondary BrC dominates in summer.
Yuning Xie, Gehui Wang, Xinpei Wang, Jianmin Chen, Yubao Chen, Guiqian Tang, Lili Wang, Shuangshuang Ge, Guoyan Xue, Yuesi Wang, and Jian Gao
Atmos. Chem. Phys., 20, 5019–5033, https://doi.org/10.5194/acp-20-5019-2020, https://doi.org/10.5194/acp-20-5019-2020, 2020
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As a result of strict emission control, nitrate-dominated PM2.5 in pollution episodes was observed in urban Beijing during the winter of 2017–2018. With the help of sufficient ammonia, particle pH could increase to near neutral (5.4) as particulate nitrate fraction increases. Further tests imply that airborne particle hygroscopicity would be enhanced at moderate RH in nitrate-dominated particles, and pH elevation will be accelerated when ammonia and particulate nitrate both increase.
Tianfeng Guo, Zhigang Guo, Juntao Wang, Jialiang Feng, Huiwang Gao, and Xiaohong Yao
Atmos. Chem. Phys., 20, 5055–5070, https://doi.org/10.5194/acp-20-5055-2020, https://doi.org/10.5194/acp-20-5055-2020, 2020
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This study investigated tracer-based organic matter observations over two marginal seas of China and the northwest Pacific Ocean in spring, when the East Asian monsoon carries biogenic and anthropogenic aerosols over these oceanic zones. The geographical difference may be related to emissions of primary particulate organics and gaseous precursors as well as formation processing of secondary organics in various atmospheres. Furthermore, we present the tracer-based estimation of organic carbon.
Jianjun Li, Qi Zhang, Gehui Wang, Jin Li, Can Wu, Lang Liu, Jiayuan Wang, Wenqing Jiang, Lijuan Li, Kin Fai Ho, and Junji Cao
Atmos. Chem. Phys., 20, 4889–4904, https://doi.org/10.5194/acp-20-4889-2020, https://doi.org/10.5194/acp-20-4889-2020, 2020
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We examined light absorption properties and molecular composition of water-soluble (WS) and water-insoluble (WI) BrC in PM2.5 collected from northwest China. We found that photochemical formation contributes significantly to light absorption of WI-BrC in summer, whereas aqueous-phase reactions play an important role in secondary WS-BrC formation in winter. BrC was estimated to account for 1.36 % and 3.74 %, respectively, of total down-welling solar radiation in the UV range in summer and winter.
Siddika Celik, Frank Drewnick, Friederike Fachinger, James Brooks, Eoghan Darbyshire, Hugh Coe, Jean-Daniel Paris, Philipp G. Eger, Jan Schuladen, Ivan Tadic, Nils Friedrich, Dirk Dienhart, Bettina Hottmann, Horst Fischer, John N. Crowley, Hartwig Harder, and Stephan Borrmann
Atmos. Chem. Phys., 20, 4713–4734, https://doi.org/10.5194/acp-20-4713-2020, https://doi.org/10.5194/acp-20-4713-2020, 2020
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Analysis of 252 ship emission plumes in the Mediterranean Sea and around the Arabian Peninsula examined particulate- and gas-phase characteristics. By identifying the corresponding ships, source features and plume age were determined. Emission factors (amount of pollutant per kilogram of fuel burned) were calculated and investigated for dependencies on source characteristics, atmospheric conditions, and transport time, providing insight into the most relevant influences on ship emissions.
August Andersson, Elena N. Kirillova, Stefano Decesari, Langley DeWitt, Jimmy Gasore, Katherine E. Potter, Ronald G. Prinn, Maheswar Rupakheti, Jean de Dieu Ndikubwimana, Julius Nkusi, and Bonfils Safari
Atmos. Chem. Phys., 20, 4561–4573, https://doi.org/10.5194/acp-20-4561-2020, https://doi.org/10.5194/acp-20-4561-2020, 2020
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Large-scale biomass burning events seasonally cover sub-Saharan Africa with air particles. In this study, we find that the concentrations of these particles at a remote mountain site in Rwanda may increase by a factor of 10 during such dry biomass burning periods, with strong implications for the regional climate and human health. These results provide quantitative constraints that could contribute to reducing the large uncertainties regarding the environmental impact of these fires.
Zhenhao Ling, Qianqian Xie, Zhe Wang, Tao Wang, Hai Guo, and Xuemei Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-212, https://doi.org/10.5194/acp-2020-212, 2020
Revised manuscript accepted for ACP
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The observation data from a receptor site in the Pearl River Delta region was analyzed by a photochemical box model with near-explicit chemical mechanisms (i.e., the master chemical mechanism, MCM), and improvements with reversible and irreversible heterogeneous processes of Glyoxal and Methylglyoxal, and the gas-particle partitioning of oxidation products in the present study.
Imre Salma, Anikó Vasanits-Zsigrai, Attila Machon, Tamás Varga, István Major, Virág Gergely, and Mihály Molnár
Atmos. Chem. Phys., 20, 4295–4312, https://doi.org/10.5194/acp-20-4295-2020, https://doi.org/10.5194/acp-20-4295-2020, 2020
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Major carbonaceous aerosol species were apportioned among FF combustion, BB and biogenic sources in various types of atmospheric environments of interest in the Carpathian Basin in different months representing different seasons. The conclusions present novel and valuable research contributions on a large area in central Europe.
Stefano Decesari, Marco Paglione, Matteo Rinaldi, Manuel Dall'Osto, Rafel Simó, Nicola Zanca, Francesca Volpi, Maria Cristina Facchini, Thorsten Hoffmann, Sven Götz, Christopher Johannes Kampf, Colin O'Dowd, Darius Ceburnis, Jurgita Ovadnevaite, and Emilio Tagliavini
Atmos. Chem. Phys., 20, 4193–4207, https://doi.org/10.5194/acp-20-4193-2020, https://doi.org/10.5194/acp-20-4193-2020, 2020
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Atmospheric aerosols in Antarctica contribute to regulate the delicate budget of cloud formation and precipitations. Besides the well-known biogenic production of sulfur-containing aerosol components such as methanesulfonate (MSA), the assessment of biological sources of organic particles in Antarctica remains an active area of research. Here we present the results of aerosol organic characterization during a research cruise performed in the Weddell Sea and in the Southern Ocean in Jan–Feb 2015.
Pengfei Liu, Can Ye, Chaoyang Xue, Chenglong Zhang, Yujing Mu, and Xu Sun
Atmos. Chem. Phys., 20, 4153–4165, https://doi.org/10.5194/acp-20-4153-2020, https://doi.org/10.5194/acp-20-4153-2020, 2020
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A vast area in China is currently going through severe haze episodes with drastically elevated concentrations of PM2.5 in winter. Nitrate and sulfate are main constituents of PM2.5, but their formations via NO2 and SO2 oxidation are still not comprehensively understood. Our results found that the gas-phase reaction of NO2 with OH and the heterogeneous hydrolysis of N2O5 play key roles in nitrate formation, and SO2 aqueous-phase oxidation with H2O2 rather than NO2 contributed greatly to sulfate.
Cited articles
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Kong, S. F., Li, L., Li, X. X., Yin, Y., Chen, K., Liu, D. T., Yuan, L., Zhang, Y. J., Shan, Y. P., and Ji, Y. Q.: The impacts of firework burning at the Chinese Spring Festival on air quality: insights of tracers, source evolution and aging processes, Atmos. Chem. Phys., 15, 2167–2184, https://doi.org/10.5194/acp-15-2167-2015, 2015.
Kulmala, M., Lappalainen, H. K., Petäjä, T., Kurten, T., Kerminen, V.-M., Viisanen, Y., Hari, P., Sorvari, S., Bäck, J., Bondur, V., Kasimov, N., Kotlyakov, V., Matvienko, G., Baklanov, A., Guo, H. D., Ding, A., Hansson, H.-C., and Zilitinkevich, S.: Introduction: The Pan-Eurasian Experiment (PEEX) – multidisciplinary, multiscale and multicomponent research and capacity-building initiative, Atmos. Chem. Phys., 15, 13085–13096, https://doi.org/10.5194/acp-15-13085-2015, 2015.
Lee, A. K. Y., Hayden, K. L., Herckes, P., Leaitch, W. R., Liggio, J., Macdonald, A. M., and Abbatt, J. P. D.: Characterization of aerosol and cloud water at a mountain site during WACS 2010: secondary organic aerosol formation through oxidative cloud processing, Atmos. Chem. Phys., 12, 7103–7116, https://doi.org/10.5194/acp-12-7103-2012, 2012.
Lee, B. P., Li, Y. J., Yu, J. Z., Louie, P. K. K., and Chan, C. K.: Physical and chemical characterization of ambient aerosol by HR-ToF-AMS at a suburban site in Hong Kong during springtime 2011, J. Geophys. Res.-Atmos., 118, 8625–8639, https://doi.org/10.1002/jgrd.50658, 2013.
Li, Y. J., Lee, B. P., Su, L., Fung, J. C. H., and Chan, C. K.: Seasonal characteristics of fine particulate matter (PM) based on high-resolution time-of-flight aerosol mass spectrometric (HR-ToF-AMS) measurements at the HKUST Supersite in Hong Kong, Atmos. Chem. Phys., 15, 37–53, https://doi.org/10.5194/acp-15-37-2015, 2015.
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Highly time- and chemically resolved submicron aerosol properties were characterized online for the first time during springtime in Nanjing by using the Aerodyne SP-AMS. Both chemical and size information of black carbon together with other aerosol species were simultaneously determined. An in-depth analysis of the data elucidates the sources and evolution processes of the fine aerosols in the YRD region. Our findings are valuable for air quality remediation in the densely populated regions.
Highly time- and chemically resolved submicron aerosol properties were characterized online for...
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