Articles | Volume 25, issue 6
https://doi.org/10.5194/acp-25-3753-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-3753-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
31 Mar 2025
Research article |
| 31 Mar 2025
| 31 Mar 2025
Mechanistic insights into chloroacetic acid production from atmospheric multiphase volatile organic compound–chlorine chemistry
Mingxue Li
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
Aerosol and Haze Laboratory, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
Chunshui Lin
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
Yifan Jiang
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
Weihang Sun
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
Yurun Wang
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
Yingnan Zhang
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
Maoxia He
Environment Research Institute, Shandong University, Qingdao 266237, China
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China
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Chunshui Lin, Darius Ceburnis, Anna Trubetskaya, Wei Xu, William Smith, Stig Hellebust, John Wenger, Colin O'Dowd, and Jurgita Ovadnevaite
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Peng Wang, Juanyong Shen, Men Xia, Shida Sun, Yanli Zhang, Hongliang Zhang, and Xinming Wang
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Wei Xu, Kirsten N. Fossum, Jurgita Ovadnevaite, Chunshui Lin, Ru-Jin Huang, Colin O'Dowd, and Darius Ceburnis
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Mengyuan Zhang, Arpit Katiyar, Shengqiang Zhu, Juanyong Shen, Men Xia, Jinlong Ma, Sri Harsha Kota, Peng Wang, and Hongliang Zhang
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Yuting Wang, Yong-Feng Ma, Domingo Muñoz-Esparza, Cathy W. Y. Li, Mary Barth, Tao Wang, and Guy P. Brasseur
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Yujiao Zhu, Likun Xue, Jian Gao, Jianmin Chen, Hongyong Li, Yong Zhao, Zhaoxin Guo, Tianshu Chen, Liang Wen, Penggang Zheng, Ye Shan, Xinfeng Wang, Tao Wang, Xiaohong Yao, and Wenxing Wang
Atmos. Chem. Phys., 21, 1305–1323, https://doi.org/10.5194/acp-21-1305-2021, https://doi.org/10.5194/acp-21-1305-2021, 2021
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This work investigates the long-term changes in new particle formation (NPF) events under reduced SO2 emissions at the summit of Mt. Tai during seven campaigns from 2007 to 2018. We found the NPF intensity increased 2- to 3-fold in 2018 compared to 2007. In contrast, the probability of new particles growing to CCN size largely decreased. Changes to biogenic VOCs and anthropogenic emissions are proposed to explain the distinct NPF characteristics.
Zhenhao Ling, Qianqian Xie, Min Shao, Zhe Wang, Tao Wang, Hai Guo, and Xuemei Wang
Atmos. Chem. Phys., 20, 11451–11467, https://doi.org/10.5194/acp-20-11451-2020, https://doi.org/10.5194/acp-20-11451-2020, 2020
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The observation data from a receptor site in the Pearl River Delta region were analyzed by a photochemical box model with near-explicit chemical mechanisms (i.e., the Master Chemical Mechanism, MCM), improvements with reversible and irreversible heterogeneous processes of glyoxal and methylglyoxal, and the gas-particle partitioning of oxidation products in the present study.
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.
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.
Wei Pu, Zhouxing Zou, Weihao Wang, David Tanner, Zhe Wang, and Tao Wang
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-252, https://doi.org/10.5194/amt-2020-252, 2020
Revised manuscript not accepted
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The hydroxyl radical (OH) is responsible for the degradation of trace gases and plays key roles in major environmental issues such as photochemical pollution. However, the measurement of atmospheric OH radical is a huge challenge due to its high reactivity. Our study provides systematic optimization of a chemical ionization mass spectrometer (CIMS) for OH measurement as a reference for other CIMS users. The ambient result demonstrates the capability of the CIMS for ambient OH measurement.
Yiming Liu and Tao Wang
Atmos. Chem. Phys., 20, 6305–6321, https://doi.org/10.5194/acp-20-6305-2020, https://doi.org/10.5194/acp-20-6305-2020, 2020
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This study revealed the effects of changes in meteorology and anthropogenic emissions on the summer ozone variations from 2013 to 2017 across China by conducting numerical experiments. We highlighted the important but varying roles of meteorology in ozone variations attributed to the synergistic or counteracting effects from individual meteorological factors. Developing future ozone pollution mitigation policies should consider the counteracting impact of meteorological changes.
Yiming Liu and Tao Wang
Atmos. Chem. Phys., 20, 6323–6337, https://doi.org/10.5194/acp-20-6323-2020, https://doi.org/10.5194/acp-20-6323-2020, 2020
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Men Xia, Xiang Peng, Weihao Wang, Chuan Yu, Peng Sun, Yuanyuan Li, Yuliang Liu, Zhengning Xu, Zhe Wang, Zheng Xu, Wei Nie, Aijun Ding, and Tao Wang
Atmos. Chem. Phys., 20, 6147–6158, https://doi.org/10.5194/acp-20-6147-2020, https://doi.org/10.5194/acp-20-6147-2020, 2020
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ClNO2 and Cl2 can be photolyzed by sunlight to produce a highly reactive Cl atom which affects air quality and climate. We observed high ClNO2 and Cl2 concentrations during a recent field study in east China. We analyzed the data and proposed a new hypothesis on the Cl2 production mechanism. Yields of ClNO2 and Cl2 from N2O2 uptake were parameterized using observational constraints, and they can be used in air quality models to improve simulations of atmospheric photochemistry and air quality.
Havala O. T. Pye, Athanasios Nenes, Becky Alexander, Andrew P. Ault, Mary C. Barth, Simon L. Clegg, Jeffrey L. Collett Jr., Kathleen M. Fahey, Christopher J. Hennigan, Hartmut Herrmann, Maria Kanakidou, James T. Kelly, I-Ting Ku, V. Faye McNeill, Nicole Riemer, Thomas Schaefer, Guoliang Shi, Andreas Tilgner, John T. Walker, Tao Wang, Rodney Weber, Jia Xing, Rahul A. Zaveri, and Andreas Zuend
Atmos. Chem. Phys., 20, 4809–4888, https://doi.org/10.5194/acp-20-4809-2020, https://doi.org/10.5194/acp-20-4809-2020, 2020
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Acid rain is recognized for its impacts on human health and ecosystems, and programs to mitigate these effects have had implications for atmospheric acidity. Historical measurements indicate that cloud and fog droplet acidity has changed in recent decades in response to controls on emissions from human activity, while the limited trend data for suspended particles indicate acidity may be relatively constant. This review synthesizes knowledge on the acidity of atmospheric particles and clouds.
Chuan Yu, Zhe Wang, Men Xia, Xiao Fu, Weihao Wang, Yee Jun Tham, Tianshu Chen, Penggang Zheng, Hongyong Li, Ye Shan, Xinfeng Wang, Likun Xue, Yan Zhou, Dingli Yue, Yubo Ou, Jian Gao, Keding Lu, Steven S. Brown, Yuanhang Zhang, and Tao Wang
Atmos. Chem. Phys., 20, 4367–4378, https://doi.org/10.5194/acp-20-4367-2020, https://doi.org/10.5194/acp-20-4367-2020, 2020
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This study provides a holistic picture of N2O5 heterogeneous uptake on ambient aerosols and the influencing factors under various climatic and chemical conditions in China, and it proposes an observation-based empirical parameterization. The empirical parameterization can be used in air quality models to improve the prediction of PM2.5 and photochemical pollution in China and similar polluted regions of the world.
Jing Duan, Ru-Jin Huang, Yongjie Li, Qi Chen, Yan Zheng, Yang Chen, Chunshui Lin, Haiyan Ni, Meng Wang, Jurgita Ovadnevaite, Darius Ceburnis, Chunying Chen, Douglas R. Worsnop, Thorsten Hoffmann, Colin O'Dowd, and Junji Cao
Atmos. Chem. Phys., 20, 3793–3807, https://doi.org/10.5194/acp-20-3793-2020, https://doi.org/10.5194/acp-20-3793-2020, 2020
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We characterized secondary aerosol formation in Beijing. Our results showed that relative humidity (RH) and Ox have opposite effects on sulfate and nitrate formation in summer and winter. The wintertime more-oxidized OOA (MO-OOA) showed a good correlation with aerosol liquid water content (ALWC). Meanwhile, the dependence of less-oxidized OOA (LO-OOA) and the mass ratio of LO-OOA to MO-OOA in Ox both degraded when RH > 60 %, suggesting that RH or ALWC may also affect LO-OOA formation.
Wei Xu, Jurgita Ovadnevaite, Kirsten N. Fossum, Chunshui Lin, Ru-Jin Huang, Colin O'Dowd, and Darius Ceburnis
Atmos. Chem. Phys., 20, 3777–3791, https://doi.org/10.5194/acp-20-3777-2020, https://doi.org/10.5194/acp-20-3777-2020, 2020
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A humidified tandem differential mobility analyser (HTDMA) and a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) were simultaneously deployed during winter at Mace Head observatory to characterise the hygroscopicity of marine aerosols and their link to chemical composition. Good agreement was generally found between measured and estimated growth factors. A significant degree of external mixing was found in all air masses manifesting primary and secondary sources.
Tao Li, Zhe Wang, Yaru Wang, Chen Wu, Yiheng Liang, Men Xia, Chuan Yu, Hui Yun, Weihao Wang, Yan Wang, Jia Guo, Hartmut Herrmann, and Tao Wang
Atmos. Chem. Phys., 20, 391–407, https://doi.org/10.5194/acp-20-391-2020, https://doi.org/10.5194/acp-20-391-2020, 2020
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This work presents a field study of cloud water chemistry and interactions of cloud, gas, and aerosols in the polluted coastal boundary layer in southern China. Substantial dissolved organic matter in the acidic cloud water was observed, and the gas- and aqueous-phase partitioning of carbonyl compounds was investigated. The results demonstrated the significant role of cloud processing in altering aerosol properties, especially in producing aqueous organics and droplet-mode aerosols.
Chunshui Lin, Darius Ceburnis, Ru-Jin Huang, Wei Xu, Teresa Spohn, Damien Martin, Paul Buckley, John Wenger, Stig Hellebust, Matteo Rinaldi, Maria Cristina Facchini, Colin O'Dowd, and Jurgita Ovadnevaite
Atmos. Chem. Phys., 19, 14091–14106, https://doi.org/10.5194/acp-19-14091-2019, https://doi.org/10.5194/acp-19-14091-2019, 2019
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To gain insight into the spatial and chemical variation in submicron aerosol, a nationwide characterization of wintertime PM1 was performed at four representative sites across Ireland. This nationwide source apportionment study highlights the large contribution of residential solid fuel burning to urban air pollution and has significant implications for aerosol regional-transport models.
Meng Wang, Ru-Jin Huang, Junji Cao, Wenting Dai, Jiamao Zhou, Chunshui Lin, Haiyan Ni, Jing Duan, Ting Wang, Yang Chen, Yongjie Li, Qi Chen, Imad El Haddad, and Thorsten Hoffmann
Atmos. Meas. Tech., 12, 4779–4789, https://doi.org/10.5194/amt-12-4779-2019, https://doi.org/10.5194/amt-12-4779-2019, 2019
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The analytical performances of SE-GC-MS and TD-GC-MS for the determination of n-alkanes, PAHs and hopanes were evaluated and compared. The two methods show a good agreement with a high correlation efficient (R2 > 0.98) and a slope close to unity. The concentrations of n-alkanes, PAHs and hopanes are found to be much higher in Beijing than those in Chengdu, Shanghai and Guangzhou, most likely due to emissions from coal combustion for wintertime heating in Beijing.
Jing Duan, Ru-Jin Huang, Chunshui Lin, Wenting Dai, Meng Wang, Yifang Gu, Ying Wang, Haobin Zhong, Yan Zheng, Haiyan Ni, Uli Dusek, Yang Chen, Yongjie Li, Qi Chen, Douglas R. Worsnop, Colin D. O'Dowd, and Junji Cao
Atmos. Chem. Phys., 19, 10319–10334, https://doi.org/10.5194/acp-19-10319-2019, https://doi.org/10.5194/acp-19-10319-2019, 2019
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We present the seasonal distinction of secondary aerosol formation in urban Beijing. Both photochemical oxidation and aqueous-phase processing played important roles in SOA (secondary organic aerosol) formation during all three seasons; while for sulfate formation, gas-phase photochemical oxidation was the major pathway in late summer, aqueous-phase reactions were more responsible during early winter, and both processes had contributions during autumn.
Lu Shen, Daniel J. Jacob, Xiong Liu, Guanyu Huang, Ke Li, Hong Liao, and Tao Wang
Atmos. Chem. Phys., 19, 6551–6560, https://doi.org/10.5194/acp-19-6551-2019, https://doi.org/10.5194/acp-19-6551-2019, 2019
Ru-Jin Huang, Yichen Wang, Junji Cao, Chunshui Lin, Jing Duan, Qi Chen, Yongjie Li, Yifang Gu, Jin Yan, Wei Xu, Roman Fröhlich, Francesco Canonaco, Carlo Bozzetti, Jurgita Ovadnevaite, Darius Ceburnis, Manjula R. Canagaratna, John Jayne, Douglas R. Worsnop, Imad El-Haddad, André S. H. Prévôt, and Colin D. O'Dowd
Atmos. Chem. Phys., 19, 2283–2298, https://doi.org/10.5194/acp-19-2283-2019, https://doi.org/10.5194/acp-19-2283-2019, 2019
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We found that in wintertime Shijiazhuang fine PM was mostly from primary emissions without sufficient atmospheric aging. In addition, secondary inorganic and organic aerosol dominated in pollution events under high-RH conditions, likely due to enhanced aqueous-phase chemistry, whereas primary organic aerosol dominated in pollution events under low-RH and stagnant conditions. Our results also highlighted the importance of meteorological conditions for PM pollution in this highly polluted city.
Xiao Fu, Tao Wang, Li Zhang, Qinyi Li, Zhe Wang, Men Xia, Hui Yun, Weihao Wang, Chuan Yu, Dingli Yue, Yan Zhou, Junyun Zheng, and Rui Han
Atmos. Chem. Phys., 19, 1–14, https://doi.org/10.5194/acp-19-1-2019, https://doi.org/10.5194/acp-19-1-2019, 2019
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This study has identified the major contributors to the observed high HONO levels during a severe winter pollution episode and highlighted the importance of HONO chemistry in the combined photochemical and haze pollution in a subtropical region. It also highlighted the critical need to include and update HONO sources in regional air quality models in order to predict ozone and other secondary pollutants better during heavy pollution events in southern China and similar regions.
Hui Yun, Weihao Wang, Tao Wang, Men Xia, Chuan Yu, Zhe Wang, Steven C. N. Poon, Dingli Yue, and Yan Zhou
Atmos. Chem. Phys., 18, 17515–17527, https://doi.org/10.5194/acp-18-17515-2018, https://doi.org/10.5194/acp-18-17515-2018, 2018
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Based on the data analysis of simultaneous measurement of N2O5 and ClNO2 in a severe winter haze in the Pearl River Delta, this study underscores the importance of N2O5 heterogeneous reactions in nitrate formation and calls for better parameterization of N2O5 heterogeneous chemistry in order to predict haze pollution in China.
Weihao Wang, Zhe Wang, Chuan Yu, Men Xia, Xiang Peng, Yan Zhou, Dingli Yue, Yubo Ou, and Tao Wang
Atmos. Meas. Tech., 11, 5643–5655, https://doi.org/10.5194/amt-11-5643-2018, https://doi.org/10.5194/amt-11-5643-2018, 2018
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This study introduces an in situ experimental approach to direct measurement of N2O5 heterogeneous reactivity in polluted environments. Laboratory tests, model simulations, and field deployment of the method at a polluted site in south China demonstrated its applicability in accurately measuring N2O5 uptake coefficient with high ambient pollutants levels and air mass changes. The introduced method is also applicable to in situ measurement of reactivity of other trace gases on ambient aerosols.
Yee Jun Tham, Zhe Wang, Qinyi Li, Weihao Wang, Xinfeng Wang, Keding Lu, Nan Ma, Chao Yan, Simonas Kecorius, Alfred Wiedensohler, Yuanhang Zhang, and Tao Wang
Atmos. Chem. Phys., 18, 13155–13171, https://doi.org/10.5194/acp-18-13155-2018, https://doi.org/10.5194/acp-18-13155-2018, 2018
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This study addresses the limited understanding of heterogeneous N2O5 uptake and ClNO2 production in the polluted environment of China. The results showed that N2O5 uptake and ClNO2 yield cannot be well explained by previous parameterizations and were largely influenced by factors like aerosol water content and biomass burning emission. Our findings illuminate the need to realistically parameterize these heterogeneous processes for better simulation of photochemical and haze pollution in China.
Michael Le Breton, Åsa M. Hallquist, Ravi Kant Pathak, David Simpson, Yujue Wang, John Johansson, Jing Zheng, Yudong Yang, Dongjie Shang, Haichao Wang, Qianyun Liu, Chak Chan, Tao Wang, Thomas J. Bannan, Michael Priestley, Carl J. Percival, Dudley E. Shallcross, Keding Lu, Song Guo, Min Hu, and Mattias Hallquist
Atmos. Chem. Phys., 18, 13013–13030, https://doi.org/10.5194/acp-18-13013-2018, https://doi.org/10.5194/acp-18-13013-2018, 2018
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We apply state-of-the-art chemical characterization to determine the chloride radical production in Beijing via measurement of inorganic halogens at a semi-rural site. The high concentration of inorganic halogens, namely nitryl chloride, enables the production of chlorinated volatile organic compounds which are measured in both the gas and particle phases simultaneously. This enables the secondary production of aerosols via chlorine oxidation to be directly observed in ambient air.
Liang Wen, Likun Xue, Xinfeng Wang, Caihong Xu, Tianshu Chen, Lingxiao Yang, Tao Wang, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 18, 11261–11275, https://doi.org/10.5194/acp-18-11261-2018, https://doi.org/10.5194/acp-18-11261-2018, 2018
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We present the first piece of observational evidence of the increasing trend of fine nitrate aerosol in the North China Plain (NCP) during 2005–2015. The summertime nitrate formation mechanism is dissected with a multiphase chemical box model based on observations at three different sites. The nitrate formation is most sensitive to NO2 and to a lesser extent to O3. NH3 plays a significant role in prompting the nitrate formation, but it is usually in excess in summer in the NCP region.
Ru-Jin Huang, Junji Cao, Yang Chen, Lu Yang, Jincan Shen, Qihua You, Kai Wang, Chunshui Lin, Wei Xu, Bo Gao, Yongjie Li, Qi Chen, Thorsten Hoffmann, Colin D. O'Dowd, Merete Bilde, and Marianne Glasius
Atmos. Meas. Tech., 11, 3447–3456, https://doi.org/10.5194/amt-11-3447-2018, https://doi.org/10.5194/amt-11-3447-2018, 2018
Liwei Wang, Xinfeng Wang, Rongrong Gu, Hao Wang, Lan Yao, Liang Wen, Fanping Zhu, Weihao Wang, Likun Xue, Lingxiao Yang, Keding Lu, Jianmin Chen, Tao Wang, Yuanghang Zhang, and Wenxing Wang
Atmos. Chem. Phys., 18, 4349–4359, https://doi.org/10.5194/acp-18-4349-2018, https://doi.org/10.5194/acp-18-4349-2018, 2018
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This study presents concentrations, variation characteristics, sources and secondary formations of nitrated phenols, a major component of brown carbon, in typical seasons at four sites in northern China. The results highlight the strong influences and contributions of anthropogenic activities, in particular coal combustion and the aging processes, to the atmospheric nitrated phenols in this region.
Zhe Wang, Weihao Wang, Yee Jun Tham, Qinyi Li, Hao Wang, Liang Wen, Xinfeng Wang, and Tao Wang
Atmos. Chem. Phys., 17, 12361–12378, https://doi.org/10.5194/acp-17-12361-2017, https://doi.org/10.5194/acp-17-12361-2017, 2017
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This work addresses unclear roles of heterogeneous N2O5 reactions and chlorine activation processes in the polluted residual layer from a mountaintop measurement in northern China. The results revealed efficient ClNO2 production in the coal-fired plumes in this region, having large impacts on next-morning photochemistry. Fast heterogeneous N2O5 reactions dominate the nocturnal NOx loss and contribute to substantial nitrate formation, which may boost the haze pollution in northern China.
Li Zhang, Qinyi Li, Tao Wang, Ravan Ahmadov, Qiang Zhang, Meng Li, and Mengyao Lv
Atmos. Chem. Phys., 17, 9733–9750, https://doi.org/10.5194/acp-17-9733-2017, https://doi.org/10.5194/acp-17-9733-2017, 2017
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Little is known of the integrated impacts of HONO and ClNO2 on lower-tropospheric ozone so far. In this study, we updated WRF-Chem with the CBMZ_ReNOM module, which considers both the sources and chemistry of HONO and ClNO2. The revised model revealed that the two reactive nitrogen compounds significantly affected the oxidation capacity and ozone formation at the surface and within the lower troposphere over polluted regions and noticeably improved summertime O3 predictions over China.
Jiaping Wang, Aki Virkkula, Yuan Gao, Shuncheng Lee, Yicheng Shen, Xuguang Chi, Wei Nie, Qiang Liu, Zheng Xu, Xin Huang, Tao Wang, Long Cui, and Aijun Ding
Atmos. Chem. Phys., 17, 2653–2671, https://doi.org/10.5194/acp-17-2653-2017, https://doi.org/10.5194/acp-17-2653-2017, 2017
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Multi-year observations at a coastal station in Hong Kong reveals that aerosol optical properties showed clear temporal variations according to the dominant sources of aerosols. LPDM modeling and correlation analysis gave similar signals about the freshness of aerosols during different seasons. Fresh emissions of particles from nearby cities and ship exhausts affected light optical properties and particle size in summer and aged air mass in winter caused larger variability of light extinction.
Yee Jun Tham, Zhe Wang, Qinyi Li, Hui Yun, Weihao Wang, Xinfeng Wang, Likun Xue, Keding Lu, Nan Ma, Birger Bohn, Xin Li, Simonas Kecorius, Johannes Größ, Min Shao, Alfred Wiedensohler, Yuanhang Zhang, and Tao Wang
Atmos. Chem. Phys., 16, 14959–14977, https://doi.org/10.5194/acp-16-14959-2016, https://doi.org/10.5194/acp-16-14959-2016, 2016
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This work addresses the unclear global significance of chlorine activation processes in the troposphere. The first high-quality measurement data set of ClNO2 in northern China revealed strong ClNO2 production in the residual layers, and demonstrated its significant effects on radical budget and ozone production. Our findings imply the widespread effects of ClNO2 over the polluted regions of northern China, which may increase photochemical and haze pollution.
Qinyi Li, Li Zhang, Tao Wang, Yee Jun Tham, Ravan Ahmadov, Likun Xue, Qiang Zhang, and Junyu Zheng
Atmos. Chem. Phys., 16, 14875–14890, https://doi.org/10.5194/acp-16-14875-2016, https://doi.org/10.5194/acp-16-14875-2016, 2016
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The regional distributions and impacts of N2O5 and ClNO2 remain poorly understood. To address the problem, we developed a chemical transport model further and conducted the first high-resolution simulation of the distributions of the two species. Our research demonstrated the significant impacts of the two gases on the lifetime of nitrogen oxides, secondary nitrate production and ozone formation in southern China and highlighted the necessity of considering this chemistry in air quality models.
Lei Sun, Likun Xue, Tao Wang, Jian Gao, Aijun Ding, Owen R. Cooper, Meiyun Lin, Pengju Xu, Zhe Wang, Xinfeng Wang, Liang Wen, Yanhong Zhu, Tianshu Chen, Lingxiao Yang, Yan Wang, Jianmin Chen, and Wenxing Wang
Atmos. Chem. Phys., 16, 10637–10650, https://doi.org/10.5194/acp-16-10637-2016, https://doi.org/10.5194/acp-16-10637-2016, 2016
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We compiled the available observations of surface O3 at Mt. Tai – the highest mountain in the North China Plain, and found a significant increase of O3 concenrations from 2003 to 2015. The observed O3 increase was mainly due to the increase of O3 precursors, especially VOCs. Our analysis shows that controlling NOx alone, in the absence of VOC controls, is not sufficient to reduce regional O3 levels in North China in a short period.
Likun Xue, Rongrong Gu, Tao Wang, Xinfeng Wang, Sandra Saunders, Donald Blake, Peter K. K. Louie, Connie W. Y. Luk, Isobel Simpson, Zheng Xu, Zhe Wang, Yuan Gao, Shuncheng Lee, Abdelwahid Mellouki, and Wenxing Wang
Atmos. Chem. Phys., 16, 9891–9903, https://doi.org/10.5194/acp-16-9891-2016, https://doi.org/10.5194/acp-16-9891-2016, 2016
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The chemical budgets and principal sources of ROx and NO3 radicals during a multi-day photochemical smog episode in Hong Kong are elucidated by an observation-constrained MCM model. NO3 was shown to be an important oxidant even during daytime in a pollution case when high aerosol loading attenuated the solar irradiation. This study suggests the potential important role of daytime NO3 chemistry in polluted atmospheres under conditions with the co-existence of abundant O3, NO2, VOCs, and aerosols.
L. K. Xue, S. M. Saunders, T. Wang, R. Gao, X. F. Wang, Q. Z. Zhang, and W. X. Wang
Geosci. Model Dev., 8, 3151–3162, https://doi.org/10.5194/gmd-8-3151-2015, https://doi.org/10.5194/gmd-8-3151-2015, 2015
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A detailed chemical mechanism including 205 reactions is developed for use in the Master Chemical Mechanism. With this new chlorine mechanism, it was found that the nocturnal formation of ClNO2 has high potential to perturb the next day's atmospheric photochemistry, by enhancing the radical production and cycling, VOC oxidation and O3 formation, in the polluted coastal environments.
T. Li, Y. Wang, W. J. Li, J. M. Chen, T. Wang, and W. X. Wang
Atmos. Chem. Phys., 15, 8987–9002, https://doi.org/10.5194/acp-15-8987-2015, https://doi.org/10.5194/acp-15-8987-2015, 2015
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Twelve trace elements in fine particles and clouds at a mountain site in southern China were investigated.
Long-range transport contributed the most to element concentrations, whereas the YRD and the area around Mt. Lushan exhibited the highest element solubility.
We demonstrated that cloud processing can enhance aerosol element solubility and increase sulfate concentration correspondingly, by irreversibly altering the morphology of metal particles in cloud droplet residues.
L. K. Xue, T. Wang, J. Gao, A. J. Ding, X. H. Zhou, D. R. Blake, X. F. Wang, S. M. Saunders, S. J. Fan, H. C. Zuo, Q. Z. Zhang, and W. X. Wang
Atmos. Chem. Phys., 14, 13175–13188, https://doi.org/10.5194/acp-14-13175-2014, https://doi.org/10.5194/acp-14-13175-2014, 2014
X. Wang, T. Wang, C. Yan, Y. J. Tham, L. Xue, Z. Xu, and Q. Zha
Atmos. Meas. Tech., 7, 1–12, https://doi.org/10.5194/amt-7-1-2014, https://doi.org/10.5194/amt-7-1-2014, 2014
L. K. Xue, T. Wang, J. Gao, A. J. Ding, X. H. Zhou, D. R. Blake, X. F. Wang, S. M. Saunders, S. J. Fan, H. C. Zuo, Q. Z. Zhang, and W. X. Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-27243-2013, https://doi.org/10.5194/acpd-13-27243-2013, 2013
Revised manuscript not accepted
L. K. Xue, T. Wang, H. Guo, D. R. Blake, J. Tang, X. C. Zhang, S. M. Saunders, and W. X. Wang
Atmos. Chem. Phys., 13, 8551–8567, https://doi.org/10.5194/acp-13-8551-2013, https://doi.org/10.5194/acp-13-8551-2013, 2013
W. Nie, T. Wang, L. K. Xue, A. J. Ding, X. F. Wang, X. M. Gao, Z. Xu, Y. C. Yu, C. Yuan, Z. S. Zhou, R. Gao, X. H. Liu, Y. Wang, S. J. Fan, S. Poon, Q. Z. Zhang, and W. X. Wang
Atmos. Chem. Phys., 12, 11985–11995, https://doi.org/10.5194/acp-12-11985-2012, https://doi.org/10.5194/acp-12-11985-2012, 2012
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Differences in the key volatile organic compound species between their emitted and ambient concentrations in ozone formation
Accurate elucidation of oxidation under heavy ozone pollution: a full suite of radical measurements in the chemically complex atmosphere
Emissions of intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from different cumulative-mileage diesel vehicles at various ambient temperatures
Characterization of nitrous acid and its potential effects on secondary pollution in the warm season in Beijing urban areas
Vertical changes in volatile organic compounds (VOCs) and impacts on photochemical ozone formation
Diurnal, seasonal, and interannual variations in δ(18O) of atmospheric O2 and its application to evaluate natural and anthropogenic changes in oxygen, carbon, and water cycles
Cloud processing of dimethyl sulfide (DMS) oxidation products limits sulfur dioxide (SO2) and carbonyl sulfide (OCS) production in the eastern North Atlantic marine boundary layer
Atmospheric carbonyl compounds are crucial in regional ozone heavy pollution: insights from the Chengdu Plain Urban Agglomeration, China
Understanding summertime peroxyacetyl nitrate (PAN) formation and its relation to aerosol pollution: insights from high-resolution measurements and modeling
Measurement report: Exploring the variations in ambient BTEX in urban Europe and their environmental health implications
Seasonal air concentration variability, gas–particle partitioning, precipitation scavenging, and air–water equilibrium of organophosphate esters in southern Canada
Measurement report: Surface exchange fluxes of HONO during the growth process of paddy fields in the Huaihe River Basin, China
Marine emissions and trade winds control the atmospheric nitrous oxide in the Galapagos Islands
Molecular and seasonal characteristics of organic vapors in urban Beijing: insights from Vocus-PTR measurements
The variations in volatile organic compounds based on the policy change for Omicron in the traffic hub of Zhengzhou
On the dynamics of ozone depletion events at Villum Research Station in the High Arctic
VOC sources and impacts at an urban Mediterranean area (Marseille – France)
Measurement report: Long-term measurements of surface ozone and trends in semi-natural sub-Saharan African ecosystems
Characterization of biogenic volatile organic compounds and their oxidation products in a stressed spruce-dominated forest close to a biogas power plant
Reactive chlorine-, sulfur-, and nitrogen-containing volatile organic compounds impact atmospheric chemistry in the megacity of Delhi during both clean and extremely polluted seasons
Analysis of the day-to-day variability of ozone vertical profiles in the lower troposphere during the 2022 Paris ACROSS campaign
Short lifetimes of organic nitrates in a sub-urban temperate forest indicate efficient assimilation of reactive nitrogen by the biosphere
Ozone deposition measurements over wheat fields in the North China Plain: variability and related factors of deposition flux and velocity
The impact of organic nitrates on summer ozone formation in Shanghai, China
Consistency evaluation of tropospheric ozone from ozonesonde and IAGOS (In-service Aircraft for a Global Observing System) observations: vertical distribution, ozonesonde types, and station–airport distance
CO2 and CO temporal variability over Mexico City from ground-based total column and surface measurements
Investigating carbonyl compounds above the Amazon rainforest using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) with NO+ chemical ionization
Measurement report: In-flight and ground-based measurements of nitrogen oxide emissions from latest-generation jet engines and 100 % sustainable aviation fuel
Measurement report: Sources, sinks, and lifetime of NOx in a suburban temperate forest at night
Measurement report: Urban ammonia and amines in Houston, Texas
Biomass-burning sources control ambient particulate matter, but traffic and industrial sources control volatile organic compound (VOC) emissions and secondary-pollutant formation during extreme pollution events in Delhi
Multi-year observations of variable incomplete combustion in the New York megacity
Observations of the vertical distributions of summertime atmospheric pollutants in Nam Co: OH production and source analysis
Spatiotemporal variations in atmospheric CH4 concentrations and enhancements in northern China based on a comprehensive dataset: Ground-based observations, TROPOMI data, inventory data and inversions
Measurement report: Elevated atmospheric ammonia may promote particle pH and HONO formation – insights from the COVID-19 pandemic
Measurement report: Vertical and temporal variability in the near-surface ozone production rate and sensitivity in an urban area in the Pearl River Delta region, China
Elevated oxidized mercury in the free troposphere: analytical advances and application at a remote continental mountaintop site
Using observed urban NOx sinks to constrain VOC reactivity and the ozone and radical budget in the Seoul Metropolitan Area
Real-world emission characteristics of VOCs from typical cargo ships and their potential contributions to secondary organic aerosol and O3 under low-sulfur fuel policies
NO3 reactivity during a summer period in a temperate forest below and above the canopy
The role of oceanic ventilation and terrestrial outflow in atmospheric non-methane hydrocarbons over the Chinese marginal seas
Concentration and source changes of nitrous acid (HONO) during the COVID-19 lockdown in Beijing
Characteristics and sources of nonmethane volatile organic compounds (NMVOCs) and O3–NOx–NMVOC relationships in Zhengzhou, China
Measurement report: TURBAN observation campaign combining street-level low-cost air quality sensors and meteorological profile measurements in Prague
Deciphering anthropogenic and biogenic contributions to selected non-methane volatile organic compound emissions in an urban area
Emission characteristics of reactive organic gases (ROGs) from industrial volatile chemical products (VCPs) in the Pearl River Delta (PRD), China
Measurement report: Enhanced photochemical formation of formic and isocyanic acids in urban regions aloft – insights from tower-based online gradient measurements
Sources of organic gases and aerosol particles and their roles in nighttime particle growth at a rural forested site in southwest Germany
Surface snow bromide and nitrate at Eureka, Canada, in early spring and implications for polar boundary layer chemistry
Opinion: Strengthening research in the Global South – atmospheric science opportunities in South America and Africa
Xudong Zheng and Shaodong Xie
Atmos. Chem. Phys., 25, 3807–3820, https://doi.org/10.5194/acp-25-3807-2025, https://doi.org/10.5194/acp-25-3807-2025, 2025
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To reduce uncertainties in identifying the key volatile organic compounds (VOCs) in ozone (O3) formation from ambient concentrations, this study comprehensively calculates the emitted VOC concentrations during both nighttime and daytime using the nitrate radical, O3, and hydroxyl radical reaction rates and ambient VOC concentrations. Based on the emitted concentrations, isoprene is one of the top three species contributing to O3 formation, which may be overlooked in observed concentrations.
Renzhi Hu, Guoxian Zhang, Haotian Cai, Jingyi Guo, Keding Lu, Xin Li, Shengrong Lou, Zhaofeng Tan, Changjin Hu, Pinhua Xie, and Wenqing Liu
Atmos. Chem. Phys., 25, 3011–3028, https://doi.org/10.5194/acp-25-3011-2025, https://doi.org/10.5194/acp-25-3011-2025, 2025
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A full suite of radical measurements (OH, HO2, RO2, and kOH) was established to accurately elucidate the limitations of oxidation in a chemically complex atmosphere. Sensitivity tests revealed that the incorporation of complex processes enabled a balance in both radical concentrations and coordinate ratios, effectively addressing the deficiency in the ozone generation mechanism. The full-chain radical detection bridged the gap between the photochemistry and the intensive oxidation level.
Shuwen Guo, Xuan Zheng, Xiao He, Lewei Zeng, Liqiang He, Xian Wu, Yifei Dai, Zihao Huang, Ting Chen, Shupei Xiao, Yan You, Sheng Xiang, Shaojun Zhang, Jingkun Jiang, and Ye Wu
Atmos. Chem. Phys., 25, 2695–2705, https://doi.org/10.5194/acp-25-2695-2025, https://doi.org/10.5194/acp-25-2695-2025, 2025
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We considered two potential influencing factors of heavy-duty diesel vehicle emissions that are rarely mentioned in the literature: cumulative mileage and ambient temperatures. The results suggest that prolonged use of heavy-duty diesel vehicles and low ambient temperatures leads to reduced engine combustion efficiency, which in turn increases tailpipe emissions significantly.
Junling Li, Chaofan Lian, Mingyuan Liu, Hao Zhang, Yongxin Yan, Yufei Song, Chun Chen, Jiaqi Wang, Haijie Zhang, Yanqin Ren, Yucong Guo, Weigang Wang, Yisheng Xu, Hong Li, Jian Gao, and Maofa Ge
Atmos. Chem. Phys., 25, 2551–2568, https://doi.org/10.5194/acp-25-2551-2025, https://doi.org/10.5194/acp-25-2551-2025, 2025
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As a key source of hydroxyl (OH) radical, nitrous acid (HONO) has attracted much attention for its important role in the atmospheric oxidant capacity (AOC) increase. In this study, we made a comparison of the ambient levels, variation patterns, sources, and formation pathway in the warm season on the basis of continuous intensive observations at an urban site of Beijing. This work highlights the importance of HONO for the AOC in the warm season.
Xiao-Bing Li, Bin Yuan, Yibo Huangfu, Suxia Yang, Xin Song, Jipeng Qi, Xianjun He, Sihang Wang, Yubin Chen, Qing Yang, Yongxin Song, Yuwen Peng, Guiqian Tang, Jian Gao, Dasa Gu, and Min Shao
Atmos. Chem. Phys., 25, 2459–2472, https://doi.org/10.5194/acp-25-2459-2025, https://doi.org/10.5194/acp-25-2459-2025, 2025
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Online vertical gradient measurements of volatile organic compounds (VOCs), ozone, and NOx were conducted based on a 325 m tall tower in urban Beijing. Vertical changes in the concentrations, compositions, key drivers, and environmental impacts of VOCs were analyzed in this study. We find that VOC species display differentiated vertical variation patterns and distinct roles in contributing to photochemical ozone formation with increasing height in the urban planetary boundary layer.
Shigeyuki Ishidoya, Satoshi Sugawara, and Atsushi Okazaki
Atmos. Chem. Phys., 25, 1965–1987, https://doi.org/10.5194/acp-25-1965-2025, https://doi.org/10.5194/acp-25-1965-2025, 2025
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The 18O/16O ratio of atmospheric oxygen, δatm(18O), is higher than that of ocean water due to isotopic effects during biospheric activities. This is known as the Dole–Morita effect, and its millennial-scale variations are recorded in ice cores. However, small variations of δatm(18O) in the present day have never been detected so far. This paper presents the first observations of diurnal, seasonal, and secular variations in δatm(18O) and applies them to evaluate oxygen, carbon, and water cycles.
Delaney B. Kilgour, Christopher M. Jernigan, Olga Garmash, Sneha Aggarwal, Shengqian Zhou, Claudia Mohr, Matt E. Salter, Joel A. Thornton, Jian Wang, Paul Zieger, and Timothy H. Bertram
Atmos. Chem. Phys., 25, 1931–1947, https://doi.org/10.5194/acp-25-1931-2025, https://doi.org/10.5194/acp-25-1931-2025, 2025
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We report simultaneous measurements of dimethyl sulfide (DMS) and hydroperoxymethyl thioformate (HPMTF) in the eastern North Atlantic. We use an observationally constrained box model to show that cloud loss is the dominant sink of HPMTF in this region over 6 weeks, resulting in large reductions in DMS-derived products that contribute to aerosol formation and growth. Our findings indicate that fast cloud processing of HPMTF must be included in global models to accurately capture the sulfur cycle.
Jiemeng Bao, Xin Zhang, Zhenhai Wu, Li Zhou, Jun Qian, Qinwen Tan, Fumo Yang, Junhui Chen, Yunfeng Li, Hefan Liu, Liqun Deng, and Hong Li
Atmos. Chem. Phys., 25, 1899–1916, https://doi.org/10.5194/acp-25-1899-2025, https://doi.org/10.5194/acp-25-1899-2025, 2025
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We studied carbonyl compounds' role in ozone pollution in the Chengdu Plain Urban Agglomeration, China. During heavy pollution in August 2019, we measured carbonyls at nine sites and analyzed their impact. Areas with higher carbonyl levels, like Chengdu, had worse ozone pollution. While their abundance matters, chemical reactions with other pollutants are the main drivers. Our findings show regional cooperation is vital to reducing ozone pollution effectively.
Baoye Hu, Naihua Chen, Rui Li, Mingqiang Huang, Jinsheng Chen, Youwei Hong, Lingling Xu, Xiaolong Fan, Mengren Li, Lei Tong, Qiuping Zheng, and Yuxiang Yang
Atmos. Chem. Phys., 25, 905–921, https://doi.org/10.5194/acp-25-905-2025, https://doi.org/10.5194/acp-25-905-2025, 2025
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Box modeling with the Master Chemical Mechanism (MCM) was used to explore summertime peroxyacetyl nitrate (PAN) formation and its link to aerosol pollution under high-ozone conditions. The MCM model is effective in the study of PAN photochemical formation and performed better during the clean period than the haze period. Machine learning analysis identified ammonia, nitrate, and fine particulate matter as the top three factors contributing to simulation bias.
Xiansheng Liu, Xun Zhang, Marvin Dufresne, Tao Wang, Lijie Wu, Rosa Lara, Roger Seco, Marta Monge, Ana Maria Yáñez-Serrano, Marie Gohy, Paul Petit, Audrey Chevalier, Marie-Pierre Vagnot, Yann Fortier, Alexia Baudic, Véronique Ghersi, Grégory Gille, Ludovic Lanzi, Valérie Gros, Leïla Simon, Heidi Héllen, Stefan Reimann, Zoé Le Bras, Michelle Jessy Müller, David Beddows, Siqi Hou, Zongbo Shi, Roy M. Harrison, William Bloss, James Dernie, Stéphane Sauvage, Philip K. Hopke, Xiaoli Duan, Taicheng An, Alastair C. Lewis, James R. Hopkins, Eleni Liakakou, Nikolaos Mihalopoulos, Xiaohu Zhang, Andrés Alastuey, Xavier Querol, and Thérèse Salameh
Atmos. Chem. Phys., 25, 625–638, https://doi.org/10.5194/acp-25-625-2025, https://doi.org/10.5194/acp-25-625-2025, 2025
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This study examines BTEX (benzene, toluene, ethylbenzene, xylenes) pollution in urban areas across seven European countries. Analyzing data from 22 monitoring sites, we found traffic and industrial activities significantly impact BTEX levels, with peaks during rush hours. The risk from BTEX exposure remains moderate, especially in high-traffic and industrial zones, highlighting the need for targeted air quality management to protect public health and improve urban air quality.
Yuening Li, Faqiang Zhan, Chubashini Shunthirasingham, Ying Duan Lei, Jenny Oh, Amina Ben Chaaben, Zhe Lu, Kelsey Lee, Frank A. P. C. Gobas, Hayley Hung, and Frank Wania
Atmos. Chem. Phys., 25, 459–472, https://doi.org/10.5194/acp-25-459-2025, https://doi.org/10.5194/acp-25-459-2025, 2025
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Organophosphate esters are important humanmade trace contaminants. Measuring them in the atmospheric gas phase, particles, precipitation, and surface water in Canada, we explore seasonal concentration variability, gas–particle partitioning, precipitation scavenging, and the air–water equilibrium. Whereas higher summer concentrations and efficient precipitation scavenging conform with expectations, the lack of a relationship between compound volatility and gas–particle partitioning is puzzling.
Fanhao Meng, Baobin Han, Min Qin, Wu Fang, Ke Tang, Dou Shao, Zhitang Liao, Jun Duan, Yan Feng, Yong Huang, Ting Ni, and Pinhua Xie
Atmos. Chem. Phys., 24, 14191–14208, https://doi.org/10.5194/acp-24-14191-2024, https://doi.org/10.5194/acp-24-14191-2024, 2024
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Comprehensive observations of HONO and NOx fluxes were conducted over paddy fields in the Huaihe River Basin. Consecutive peaks in HONO and NO fluxes suggest a potentially enhanced release of HONO and NO due to soil tillage, whereas waterlogged soil may inhibit microbial nitrification processes following irrigation. Notably, biological processes and light-driven NO2 reactions at the surface may serve as sources of HONO and influence the local HONO budget during rotary tillage.
Timur Cinay, Dickon Young, Nazaret Narváez Jimenez, Cristina Vintimilla-Palacios, Ariel Pila Alonso, Paul B. Krummel, William Vizuete, and Andrew R. Babbin
EGUsphere, https://doi.org/10.5194/egusphere-2024-3769, https://doi.org/10.5194/egusphere-2024-3769, 2024
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We present the initial 15 months of nitrous oxide measurements from the Galapagos Emissions Monitoring Station. The observed variability in atmospheric mole fractions during this period can be linked to several factors: seasonal variations in trade wind speed and direction across the eastern Pacific, differences in the transport history of air masses sampled, and spatiotemporal heterogeneity in regional marine nitrous oxide emissions from coastal upwelling systems of Peru and Chile.
Zhaojin An, Rujing Yin, Xinyan Zhao, Xiaoxiao Li, Yuyang Li, Yi Yuan, Junchen Guo, Yiqi Zhao, Xue Li, Dandan Li, Yaowei Li, Dongbin Wang, Chao Yan, Kebin He, Douglas R. Worsnop, Frank N. Keutsch, and Jingkun Jiang
Atmos. Chem. Phys., 24, 13793–13810, https://doi.org/10.5194/acp-24-13793-2024, https://doi.org/10.5194/acp-24-13793-2024, 2024
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Online Vocus-PTR measurements show the compositions and seasonal variations in organic vapors in urban Beijing. With enhanced sensitivity and mass resolution, various species at a level of sub-parts per trillion (ppt) and organics with multiple oxygens (≥ 3) were observed. The fast photooxidation process in summer leads to an increase in both concentration and proportion of organics with multiple oxygens, while, in other seasons, the variations in them could be influenced by mixed sources.
Bowen Zhang, Dong Zhang, Zhe Dong, Xinshuai Song, Ruiqin Zhang, and Xiao Li
Atmos. Chem. Phys., 24, 13587–13601, https://doi.org/10.5194/acp-24-13587-2024, https://doi.org/10.5194/acp-24-13587-2024, 2024
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To gain insight into the impact of changes due to epidemic control policies, we undertook continuous online monitoring of volatile organic compounds (VOCs) at an urban site in Zhengzhou over a 2-month period. This study examines the characteristics of VOCs, their sources, and their temporal evolution. It also assesses the impact of the policy change on VOC pollution during the monitoring period, thus providing a basis for further research on VOC pollution and source control.
Jakob Boyd Pernov, Jens Liengaard Hjorth, Lise Lotte Sørensen, and Henrik Skov
Atmos. Chem. Phys., 24, 13603–13631, https://doi.org/10.5194/acp-24-13603-2024, https://doi.org/10.5194/acp-24-13603-2024, 2024
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Arctic ozone depletion events (ODEs) occur every spring and have vast implications for the oxidizing capacity, radiative balance, and mercury oxidation. In this study, we analyze ozone, ODEs, and their connection to meteorological and air mass history variables through statistical analyses, back trajectories, and machine learning (ML) at Villum Research Station. ODEs are favorable under sunny, calm conditions with air masses arriving from northerly wind directions with sea ice contact.
Marvin Dufresne, Thérèse Salameh, Thierry Léonardis, Grégory Gille, Alexandre Armengaud, and Stéphane Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-3576, https://doi.org/10.5194/egusphere-2024-3576, 2024
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This paper is about the eighteen-months measurement of Non-Methane Hydrocarbons (NMHC) at Marseille, were there was no measurement since early 2000 despite the impact of NMHC on air quality and climate. The traffic related sources are the first contributor to NMHC concentrations in Marseille and shipping strongly contribute to the formation of aerosols. Finally, the lockdown due to the Covid-19 had an impact on NMHC concentrations reaching a fifty percents decreasing for traffic-related sources.
Hagninou Elagnon Venance Donnou, Aristide Barthélémy Akpo, Money Ossohou, Claire Delon, Véronique Yoboué, Dungall Laouali, Marie Ouafo-Leumbe, Pieter Gideon Van Zyl, Ousmane Ndiaye, Eric Gardrat, Maria Dias-Alves, and Corinne Galy-Lacaux
Atmos. Chem. Phys., 24, 13151–13182, https://doi.org/10.5194/acp-24-13151-2024, https://doi.org/10.5194/acp-24-13151-2024, 2024
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Ozone is a secondary air pollutant that is detrimental to human and plant health. A better understanding of its chemical evolution is a challenge for Africa, where it is still undersampled. Out of 14 sites examined (1995–2020), high levels of O3 are reported in southern Africa. The dominant chemical processes leading to O3 formation are identified. A decrease in O3 is observed at Katibougou (Mali) and Banizoumbou (Niger), and an increase is found at Zoétélé (Cameroon) and Skukuza (South Africa).
Junwei Song, Georgios I. Gkatzelis, Ralf Tillmann, Nicolas Brüggemann, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 13199–13217, https://doi.org/10.5194/acp-24-13199-2024, https://doi.org/10.5194/acp-24-13199-2024, 2024
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Biogenic volatile organic compounds (BVOCs) and organic aerosol (OA) particles were measured online in a stressed spruce-dominated forest. OA was mainly attributed to the monoterpene oxidation products. The mixing ratios of BVOCs were higher than the values previously measured in other temperate forests. The results demonstrate that BVOCs are influenced not only by meteorology and biogenic emissions but also by local anthropogenic emissions and subsequent chemical transformation processes.
Sachin Mishra, Vinayak Sinha, Haseeb Hakkim, Arpit Awasthi, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Baerbel Sinha, and Madhavan N. Rajeevan
Atmos. Chem. Phys., 24, 13129–13150, https://doi.org/10.5194/acp-24-13129-2024, https://doi.org/10.5194/acp-24-13129-2024, 2024
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We quantified 111 gases using mass spectrometry to understand how seasonal and emission changes lead from clean air in the monsoon season to extremely polluted air in the post-monsoon season in Delhi. Averaged total mass concentrations (260 µg m-3) were > 4 times in polluted periods, driven by biomass burning emissions and reduced atmospheric ventilation. Reactive gaseous nitrogen, chlorine, and sulfur compounds hitherto unreported from such a polluted environment were discovered.
Gérard Ancellet, Camille Viatte, Anne Boynard, François Ravetta, Jacques Pelon, Cristelle Cailteau-Fischbach, Pascal Genau, Julie Capo, Axel Roy, and Philippe Nédélec
Atmos. Chem. Phys., 24, 12963–12983, https://doi.org/10.5194/acp-24-12963-2024, https://doi.org/10.5194/acp-24-12963-2024, 2024
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Characterization of ozone pollution in urban areas benefited from a measurement campaign in summer 2022 in the Paris region. The analysis is based on 21 d of lidar and aircraft observations. The main objective is an analysis of the sensitivity of ozone pollution to the micrometeorological processes in the urban atmospheric boundary layer and the transport of regional pollution. The paper also discusses to what extent satellite observations can track observed ozone plumes.
Simone T. Andersen, Rolf Sander, Patrick Dewald, Laura Wüst, Tobias Seubert, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Chaoyang Xue, Abdelwahid Mellouki, Alexandre Kukui, Vincent Michoud, Manuela Cirtog, Mathieu Cazaunau, Astrid Bauville, Hichem Bouzidi, Paola Formenti, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Christopher Cantrell, Jos Lelieveld, and John N. Crowley
EGUsphere, https://doi.org/10.5194/egusphere-2024-3437, https://doi.org/10.5194/egusphere-2024-3437, 2024
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Measurements and modelling of reactive nitrogen gases observed in a suburban temperate forest in Rambouillet, France circa 50 km southwest of Paris in 2022 indicate that the biosphere rapidly scavenges organic nitrates of mixed biogenic and anthropogenic origin, resulting in short lifetimes for e.g. alkyl nitrates and peroxy nitrates.
Xiaoyi Zhang, Wanyun Xu, Weili Lin, Gen Zhang, Jinjian Geng, Li Zhou, Huarong Zhao, Sanxue Ren, Guangsheng Zhou, Jianmin Chen, and Xiaobin Xu
Atmos. Chem. Phys., 24, 12323–12340, https://doi.org/10.5194/acp-24-12323-2024, https://doi.org/10.5194/acp-24-12323-2024, 2024
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Ozone (O3) deposition is a key process that removes surface O3, affecting air quality, ecosystems and climate change. We conducted O3 deposition measurement over a wheat canopy using a newly relaxed eddy accumulation flux system. Large variabilities in O3 deposition were detected, mainly determined by crop growth and modulated by various environmental factors. More O3 deposition observations over different surfaces are needed for exploring deposition mechanisms and model optimization.
Chunmeng Li, Xiaorui Chen, Haichao Wang, Tianyu Zhai, Xuefei Ma, Xinping Yang, Shiyi Chen, Min Zhou, Shengrong Lou, Xin Li, Limin Zeng, and Keding Lu
EGUsphere, https://doi.org/10.5194/egusphere-2024-3337, https://doi.org/10.5194/egusphere-2024-3337, 2024
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This study reports an observation of organic nitrate (including total peroxy nitrates and total alkyl nitrates) in Shanghai, China during the summer of 2021, by a homemade thermal dissociation cavity-enhanced absorption spectrometer (TD-CEAS, Atmos. Meas. Tech., 14, 4033–4051, 2021). The distribution of organic nitrates and their effects on local ozone production are analyzed based on the field observation in conjunction with model simulation.
Honglei Wang, David W. Tarasick, Jane Liu, Herman G. J. Smit, Roeland Van Malderen, Lijuan Shen, Romain Blot, and Tianliang Zhao
Atmos. Chem. Phys., 24, 11927–11942, https://doi.org/10.5194/acp-24-11927-2024, https://doi.org/10.5194/acp-24-11927-2024, 2024
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In this study, we identify 23 suitable pairs of sites from World Ozone and Ultraviolet Radiation Data Centre (WOUDC) and In-service Aircraft for a Global Observing System (IAGOS) datasets (1995 to 2021), compare the average vertical distributions of tropospheric O3 from ozonesonde and aircraft measurements, and analyze the differences based on ozonesonde type and station–airport distance.
Noémie Taquet, Wolfgang Stremme, María Eugenia González del Castillo, Victor Almanza, Alejandro Bezanilla, Olivier Laurent, Carlos Alberti, Frank Hase, Michel Ramonet, Thomas Lauvaux, Ke Che, and Michel Grutter
Atmos. Chem. Phys., 24, 11823–11848, https://doi.org/10.5194/acp-24-11823-2024, https://doi.org/10.5194/acp-24-11823-2024, 2024
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We characterize the variability in CO and CO2 emissions over Mexico City from long-term time-resolved Fourier transform infrared spectroscopy solar absorption and surface measurements from 2013 to 2021. Using the average intraday CO growth rate from total columns, the average CO / CO2 ratio and TROPOMI data, we estimate the interannual variability in the CO and CO2 anthropogenic emissions of Mexico City, highlighting the effect of an unprecedented drop in activity due to the COVID-19 lockdown.
Akima Ringsdorf, Achim Edtbauer, Bruna Holanda, Christopher Poehlker, Marta O. Sá, Alessandro Araújo, Jürgen Kesselmeier, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 24, 11883–11910, https://doi.org/10.5194/acp-24-11883-2024, https://doi.org/10.5194/acp-24-11883-2024, 2024
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We show the average height distribution of separately observed aldehydes and ketones over a day and discuss their rainforest-specific sources and sinks as well as their seasonal changes above the Amazon. Ketones have much longer atmospheric lifetimes than aldehydes and thus different implications for atmospheric chemistry. However, they are commonly observed together, which we overcome by measuring with a NO+ chemical ionization mass spectrometer for the first time in the Amazon rainforest.
Theresa Harlass, Rebecca Dischl, Stefan Kaufmann, Raphael Märkl, Daniel Sauer, Monika Scheibe, Paul Stock, Tiziana Bräuer, Andreas Dörnbrack, Anke Roiger, Hans Schlager, Ulrich Schumann, Magdalena Pühl, Tobias Schripp, Tobias Grein, Linda Bondorf, Charles Renard, Maxime Gauthier, Mark Johnson, Darren Luff, Paul Madden, Peter Swann, Denise Ahrens, Reetu Sallinen, and Christiane Voigt
Atmos. Chem. Phys., 24, 11807–11822, https://doi.org/10.5194/acp-24-11807-2024, https://doi.org/10.5194/acp-24-11807-2024, 2024
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Emissions from aircraft have a direct impact on our climate. Here, we present airborne and ground-based measurement data of nitrogen oxides that were collected in the exhaust of an Airbus aircraft. We study the impact of burning fossil and sustainable aviation fuel on nitrogen oxide emissions at different engine settings related to combustor temperature, pressure and fuel flow. Further, we compare observations with engine emission models.
Simone T. Andersen, Max R. McGillen, Chaoyang Xue, Tobias Seubert, Patrick Dewald, Gunther N. T. E. Türk, Jan Schuladen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Abdelwahid Mellouki, Lucy J. Carpenter, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 11603–11618, https://doi.org/10.5194/acp-24-11603-2024, https://doi.org/10.5194/acp-24-11603-2024, 2024
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Using measurements of various trace gases in a suburban forest near Paris in the summer of 2022, we were able to gain insight into the sources and sinks of NOx (NO+NO2) with a special focus on their nighttime chemical and physical loss processes. NO was observed as a result of nighttime soil emissions when O3 levels were strongly depleted by deposition. NO oxidation products were not observed at night, indicating that soil and/or foliar surfaces are an efficient sink of reactive N.
Lee Tiszenkel, James H. Flynn, and Shan-Hu Lee
Atmos. Chem. Phys., 24, 11351–11363, https://doi.org/10.5194/acp-24-11351-2024, https://doi.org/10.5194/acp-24-11351-2024, 2024
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Ammonia and amines are important ingredients for aerosol formation in urban environments, but the measurements of these compounds are extremely challenging. Our observations show that urban ammonia and amines in Houston are emitted from urban sources, and diurnal variations in their concentrations are likely governed by gas-to-particle conversion and emissions.
Arpit Awasthi, Baerbel Sinha, Haseeb Hakkim, Sachin Mishra, Varkrishna Mummidivarapu, Gurmanjot Singh, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Vinayak Sinha, and Madhavan N. Rajeevan
Atmos. Chem. Phys., 24, 10279–10304, https://doi.org/10.5194/acp-24-10279-2024, https://doi.org/10.5194/acp-24-10279-2024, 2024
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We use 111 volatile organic compounds (VOCs), PM10, and PM2.5 in a positive matrix factorization (PMF) model to resolve 11 pollution sources validated with chemical fingerprints. Crop residue burning and heating account for ~ 50 % of the PM, while traffic and industrial emissions dominate the gas-phase VOC burden and formation potential of secondary organic aerosols (> 60 %). Non-tailpipe emissions from compressed-natural-gas-fuelled commercial vehicles dominate the transport sector's PM burden.
Luke D. Schiferl, Cong Cao, Bronte Dalton, Andrew Hallward-Driemeier, Ricardo Toledo-Crow, and Róisín Commane
Atmos. Chem. Phys., 24, 10129–10142, https://doi.org/10.5194/acp-24-10129-2024, https://doi.org/10.5194/acp-24-10129-2024, 2024
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Carbon monoxide (CO) is an air pollutant and an important indicator of the incomplete combustion of fossil fuels in cities. Using 4 years of winter and spring observations in New York City, we found that both the magnitude and variability of CO from the metropolitan area are greater than expected. Transportation emissions cannot explain the missing and variable CO, which points to energy from buildings as a likely underappreciated source of urban air pollution and greenhouse gas emissions.
Chengzhi Xing, Cheng Liu, Chunxiang Ye, Jingkai Xue, Hongyu Wu, Xiangguang Ji, Jinping Ou, and Qihou Hu
Atmos. Chem. Phys., 24, 10093–10112, https://doi.org/10.5194/acp-24-10093-2024, https://doi.org/10.5194/acp-24-10093-2024, 2024
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We identified the contributions of ozone (O3) and nitrous acid (HONO) to the production rates of hydroxide (OH) in vertical space on the Tibetan Plateau (TP). A new insight was offered: the contributions of HONO and O3 to the production rates of OH on the TP are even greater than in lower-altitudes areas. This study enriches the understanding of vertical distribution of atmospheric components and explains the strong atmospheric oxidation capacity (AOC) on the TP.
Pengfei Han, Ning Zeng, Bo Yao, Wen Zhang, Weijun Quan, Pucai Wang, Ting Wang, Minqiang Zhou, Qixiang Cai, Yuzhong Zhang, Ruosi Liang, Wanqi Sun, and Shengxiang Liu
EGUsphere, https://doi.org/10.5194/egusphere-2024-2162, https://doi.org/10.5194/egusphere-2024-2162, 2024
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Methane (CH4) is a potent greenhouse gas. Northern China contributes a large proportion of CH4 emissions yet large observation gaps are existed. Here we compiled a comprehensive dataset which is publicly available including ground-based, satellite-based, inventory and modeling results, to show the CH4 concentrations, enhancements and spatial-temporal variations. The data can benefit the research community, and policy makers for future observations, atmospheric inversions and policy-making.
Xinyuan Zhang, Lingling Wang, Nan Wang, Shuangliang Ma, Shenbo Wang, Ruiqin Zhang, Dong Zhang, Mingkai Wang, and Hongyu Zhang
Atmos. Chem. Phys., 24, 9885–9898, https://doi.org/10.5194/acp-24-9885-2024, https://doi.org/10.5194/acp-24-9885-2024, 2024
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This study highlights the importance of the redox reaction of NO2 with SO2 based on actual atmospheric observations. The particle pH in future China is expected to rise steadily. Consequently, this reaction could become a significant source of HONO in China. Therefore, it is crucial to coordinate the control of SO2, NOx, and NH3 emissions to avoid a rapid increase in the particle pH.
Jun Zhou, Chunsheng Zhang, Aiming Liu, Bin Yuan, Yan Wang, Wenjie Wang, Jie-Ping Zhou, Yixin Hao, Xiao-Bing Li, Xianjun He, Xin Song, Yubin Chen, Suxia Yang, Shuchun Yang, Yanfeng Wu, Bin Jiang, Shan Huang, Junwen Liu, Yuwen Peng, Jipeng Qi, Minhui Deng, Bowen Zhong, Yibo Huangfu, and Min Shao
Atmos. Chem. Phys., 24, 9805–9826, https://doi.org/10.5194/acp-24-9805-2024, https://doi.org/10.5194/acp-24-9805-2024, 2024
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In-depth understanding of the near-ground vertical variability in photochemical ozone (O3) formation is crucial for mitigating O3 pollution. Utilizing a self-built vertical observation system, a direct net photochemical O3 production rate detection system, and an observation-based model, we diagnosed the vertical distributions and formation mechanism of net photochemical O3 production rates and sensitivity in the Pearl River Delta region, one of the most O3-polluted areas in China.
Eleanor J. Derry, Tyler R. Elgiar, Taylor Y. Wilmot, Nicholas W. Hoch, Noah S. Hirshorn, Peter Weiss-Penzias, Christopher F. Lee, John C. Lin, A. Gannet Hallar, Rainer Volkamer, Seth N. Lyman, and Lynne E. Gratz
Atmos. Chem. Phys., 24, 9615–9643, https://doi.org/10.5194/acp-24-9615-2024, https://doi.org/10.5194/acp-24-9615-2024, 2024
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Mercury (Hg) is a globally distributed neurotoxic pollutant. Atmospheric deposition is the main source of Hg in ecosystems. However, measurement biases hinder understanding of the origins and abundance of the more bioavailable oxidized form. We used an improved, calibrated measurement system to study air mass composition and transport of atmospheric Hg at a remote mountaintop site in the central US. Oxidized Hg originated upwind in the low to middle free troposphere under clean, dry conditions.
Benjamin A. Nault, Katherine R. Travis, James H. Crawford, Donald R. Blake, Pedro Campuzano-Jost, Ronald C. Cohen, Joshua P. DiGangi, Glenn S. Diskin, Samuel R. Hall, L. Gregory Huey, Jose L. Jimenez, Kyung-Eun Min, Young Ro Lee, Isobel J. Simpson, Kirk Ullmann, and Armin Wisthaler
Atmos. Chem. Phys., 24, 9573–9595, https://doi.org/10.5194/acp-24-9573-2024, https://doi.org/10.5194/acp-24-9573-2024, 2024
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Ozone (O3) is a pollutant formed from the reactions of gases emitted from various sources. In urban areas, the density of human activities can increase the O3 formation rate (P(O3)), thus impacting air quality and health. Observations collected over Seoul, South Korea, are used to constrain P(O3). A high local P(O3) was found; however, local P(O3) was partly reduced due to compounds typically ignored. These observations also provide constraints for unmeasured compounds that will impact P(O3).
Fan Zhang, Binyu Xiao, Zeyu Liu, Yan Zhang, Chongguo Tian, Rui Li, Can Wu, Yali Lei, Si Zhang, Xinyi Wan, Yubao Chen, Yong Han, Min Cui, Cheng Huang, Hongli Wang, Yingjun Chen, and Gehui Wang
Atmos. Chem. Phys., 24, 8999–9017, https://doi.org/10.5194/acp-24-8999-2024, https://doi.org/10.5194/acp-24-8999-2024, 2024
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Mandatory use of low-sulfur fuel due to global sulfur limit regulations means large uncertainties in volatile organic compound (VOC) emissions. On-board tests of VOCs from nine cargo ships in China were carried out. Results showed that switching from heavy-fuel oil to diesel increased emission factor VOCs by 48 % on average, enhancing O3 and the secondary organic aerosol formation potential. Thus, implementing a global ultra-low-sulfur oil policy needs to be optimized in the near future.
Patrick Dewald, Tobias Seubert, Simone T. Andersen, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Chaoyang Xue, Abdelwahid Mellouki, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 8983–8997, https://doi.org/10.5194/acp-24-8983-2024, https://doi.org/10.5194/acp-24-8983-2024, 2024
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In the scope of a field campaign in a suburban forest near Paris in the summer of 2022, we measured the reactivity of the nitrate radical NO3 towards biogenic volatile organic compounds (BVOCs; e.g. monoterpenes) mainly below but also above the canopy. NO3 reactivity was the highest during nights with strong temperature inversions and decreased strongly with height. Reactions with BVOCs were the main removal process of NO3 throughout the diel cycle below the canopy.
Jian Wang, Lei Xue, Qianyao Ma, Feng Xu, Gaobin Xu, Shibo Yan, Jiawei Zhang, Jianlong Li, Honghai Zhang, Guiling Zhang, and Zhaohui Chen
Atmos. Chem. Phys., 24, 8721–8736, https://doi.org/10.5194/acp-24-8721-2024, https://doi.org/10.5194/acp-24-8721-2024, 2024
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This study investigated the distribution and sources of non-methane hydrocarbons (NMHCs) in the lower atmosphere over the marginal seas of China. NMHCs, a subset of volatile organic compounds (VOCs), play a crucial role in atmospheric chemistry. Derived from systematic atmospheric sampling in coastal cities and marginal sea regions, this study offers valuable insights into the interaction between land and sea in shaping offshore atmospheric NMHCs.
Yusheng Zhang, Feixue Zheng, Zemin Feng, Chaofan Lian, Weigang Wang, Xiaolong Fan, Wei Ma, Zhuohui Lin, Chang Li, Gen Zhang, Chao Yan, Ying Zhang, Veli-Matti Kerminen, Federico Bianch, Tuukka Petäjä, Juha Kangasluoma, Markku Kulmala, and Yongchun Liu
Atmos. Chem. Phys., 24, 8569–8587, https://doi.org/10.5194/acp-24-8569-2024, https://doi.org/10.5194/acp-24-8569-2024, 2024
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The nitrous acid (HONO) budget was validated during a COVID-19 lockdown event. The main conclusions are (1) HONO concentrations showed a significant decrease from 0.97 to 0.53 ppb during lockdown; (2) vehicle emissions accounted for 53 % of nighttime sources, with the heterogeneous conversion of NO2 on ground surfaces more important than aerosol; and (3) the dominant daytime source shifted from the homogenous reaction between NO and OH (51 %) to nitrate photolysis (53 %) during lockdown.
Dong Zhang, Xiao Li, Minghao Yuan, Yifei Xu, Qixiang Xu, Fangcheng Su, Shenbo Wang, and Ruiqin Zhang
Atmos. Chem. Phys., 24, 8549–8567, https://doi.org/10.5194/acp-24-8549-2024, https://doi.org/10.5194/acp-24-8549-2024, 2024
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The increasing concentration of O3 precursors and unfavorable meteorological conditions are key factors in the formation of O3 pollution in Zhengzhou. Vehicular exhausts (28 %), solvent usage (27 %), and industrial production (22 %) are identified as the main sources of NMVOCs. Moreover, O3 formation in Zhengzhou is found to be in an anthropogenic volatile organic compound (AVOC)-limited regime. Thus, to reduce O3 formation, a minimum AVOCs / NOx reduction ratio ≥ 3 : 1 is recommended.
Petra Bauerová, Josef Keder, Adriana Šindelářová, Ondřej Vlček, William Patiño, Jaroslav Resler, Pavel Krč, Jan Geletič, Hynek Řezníček, Martin Bureš, Kryštof Eben, Michal Belda, Jelena Radović, Vladimír Fuka, Radek Jareš, and Igor Ezau
EGUsphere, https://doi.org/10.5194/egusphere-2024-1222, https://doi.org/10.5194/egusphere-2024-1222, 2024
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We implemented an observation campaign focused on street-level air quality and vertical meteorological profile measurement in Prague using low-cost sensors and remote sensing devices. Low-cost sensors have undergone long-term field testing, own data correction and drift evaluation procedures. A high level of NO2 pollution was confirmed due to the traffic load in streets, peaks of aerosol pollution appeared more under inversion conditions. The data will be further used for PALM model validation.
Arianna Peron, Martin Graus, Marcus Striednig, Christian Lamprecht, Georg Wohlfahrt, and Thomas Karl
Atmos. Chem. Phys., 24, 7063–7083, https://doi.org/10.5194/acp-24-7063-2024, https://doi.org/10.5194/acp-24-7063-2024, 2024
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The anthropogenic fraction of non-methane volatile organic compound (NMVOC) emissions associated with biogenic sources (e.g., terpenes) is investigated based on eddy covariance observations. The anthropogenic fraction of terpene emissions is strongly dependent on season. When analyzing volatile chemical product (VCP) emissions in urban environments, we caution that observations from short-term campaigns might over-/underestimate their significance depending on local and seasonal circumstances.
Sihang Wang, Bin Yuan, Xianjun He, Ru Cui, Xin Song, Yubin Chen, Caihong Wu, Chaomin Wang, Yibo Huangfu, Xiao-Bing Li, Boguang Wang, and Min Shao
Atmos. Chem. Phys., 24, 7101–7121, https://doi.org/10.5194/acp-24-7101-2024, https://doi.org/10.5194/acp-24-7101-2024, 2024
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Emissions of reactive organic gases from industrial volatile chemical product sources are measured. There are large differences among these industrial sources. We show that oxygenated species account for significant contributions to reactive organic gas emissions, especially for industrial sources utilizing water-borne chemicals.
Qing Yang, Xiao-Bing Li, Bin Yuan, Xiaoxiao Zhang, Yibo Huangfu, Lei Yang, Xianjun He, Jipeng Qi, and Min Shao
Atmos. Chem. Phys., 24, 6865–6882, https://doi.org/10.5194/acp-24-6865-2024, https://doi.org/10.5194/acp-24-6865-2024, 2024
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Online vertical gradient measurements of formic and isocyanic acids were made based on a 320 m tower in a megacity. Vertical variations and sources of the two acids were analyzed in this study. We find that formic and isocyanic acids exhibited positive vertical gradients and were mainly contributed by photochemical formations. The formation of formic and isocyanic acids was also significantly enhanced in urban regions aloft.
Junwei Song, Harald Saathoff, Feng Jiang, Linyu Gao, Hengheng Zhang, and Thomas Leisner
Atmos. Chem. Phys., 24, 6699–6717, https://doi.org/10.5194/acp-24-6699-2024, https://doi.org/10.5194/acp-24-6699-2024, 2024
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This study presents concurrent online measurements of organic gas and particles (VOCs and OA) at a forested site in summer. Both VOCs and OA were largely contributed by oxygenated organic compounds. Semi-volatile oxygenated OA and organic nitrate formed from monoterpenes and sesquiterpenes contributed significantly to nighttime particle growth. The results help us to understand the causes of nighttime particle growth regularly observed in summer in central European rural forested environments.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
Atmos. Chem. Phys., 24, 5863–5886, https://doi.org/10.5194/acp-24-5863-2024, https://doi.org/10.5194/acp-24-5863-2024, 2024
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This study uses snow samples collected from a Canadian high Arctic site, Eureka, to demonstrate that surface snow in early spring is a net sink of atmospheric bromine and nitrogen. Surface snow bromide and nitrate are significantly correlated, indicating the oxidation of reactive nitrogen is accelerated by reactive bromine. In addition, we show evidence that snow photochemical release of reactive bromine is very weak, and its emission flux is much smaller than the deposition flux of bromide.
Rebecca M. Garland, Katye E. Altieri, Laura Dawidowski, Laura Gallardo, Aderiana Mbandi, Nestor Y. Rojas, and N'datchoh E. Touré
Atmos. Chem. Phys., 24, 5757–5764, https://doi.org/10.5194/acp-24-5757-2024, https://doi.org/10.5194/acp-24-5757-2024, 2024
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This opinion piece focuses on two geographical areas in the Global South where the authors are based that are underrepresented in atmospheric science. This opinion provides context on common challenges and constraints, with suggestions on how the community can address these. The focus is on the strengths of atmospheric science research in these regions. It is these strengths, we believe, that highlight the critical role of Global South researchers in the future of atmospheric science research.
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Short summary
Our field campaigns observed a strong diel pattern of chloroacetic acid as well as a strong correlation between its level and that of reactive chlorine species at a coastal site. Using quantum chemical calculations and box model simulation with an updated Master Chemical Mechanism, we found that the formation pathway of chloroacetic acid involved multiphase processes. Our study enhances understanding of atmospheric organic chlorine chemistry and emphasizes the importance of multiphase reactions.
Our field campaigns observed a strong diel pattern of chloroacetic acid as well as a strong...
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