Articles | Volume 18, issue 15
https://doi.org/10.5194/acp-18-11261-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-18-11261-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Summertime fine particulate nitrate pollution in the North China Plain: increasing trends, formation mechanisms and implications for control policy
Liang Wen
Environment Research Institute, Shandong University, Jinan, Shandong, China
Likun Xue
CORRESPONDING AUTHOR
Environment Research Institute, Shandong University, Jinan, Shandong, China
Xinfeng Wang
Environment Research Institute, Shandong University, Jinan, Shandong, China
Caihong Xu
Environment Research Institute, Shandong University, Jinan, Shandong, China
Tianshu Chen
Environment Research Institute, Shandong University, Jinan, Shandong, China
Lingxiao Yang
Environment Research Institute, Shandong University, Jinan, Shandong, China
Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
Qingzhu Zhang
Environment Research Institute, Shandong University, Jinan, Shandong, China
Wenxing Wang
Environment Research Institute, Shandong University, Jinan, Shandong, China
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Men Xia, Xiang Peng, Weihao Wang, Chuan Yu, Zhe Wang, Yee Jun Tham, Jianmin Chen, Hui Chen, Yujing Mu, Chenglong Zhang, Pengfei Liu, Likun Xue, Xinfeng Wang, Jian Gao, Hong Li, and Tao Wang
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ClNO2 is an important precursor of chlorine radical that affects photochemistry. However, its production and impact are not well understood. Our study presents field observations of ClNO2 at three sites in northern China. These observations provide new insights into nighttime processes that produce ClNO2 and the significant impact of ClNO2 on secondary pollutions during daytime. The results improve the understanding of photochemical pollution in the lower part of the atmosphere.
Thierno Doumbia, Claire Granier, Nellie Elguindi, Idir Bouarar, Sabine Darras, Guy Brasseur, Benjamin Gaubert, Yiming Liu, Xiaoqin Shi, Trissevgeni Stavrakou, Simone Tilmes, Forrest Lacey, Adrien Deroubaix, and Tao Wang
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Most countries around the world have implemented control measures to combat the spread of the COVID-19 pandemic, resulting in significant changes in economic and personal activities. We developed the CONFORM (COvid-19 adjustmeNt Factors fOR eMissions) dataset to account for changes in emissions during lockdowns. This dataset was created with the intention of being directly applicable to existing global and regional inventories used in chemical transport models.
Yingnan Zhang, Likun Xue, William P. L. Carter, Chenglei Pei, Tianshu Chen, Jiangshan Mu, Yujun Wang, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 21, 11053–11068, https://doi.org/10.5194/acp-21-11053-2021, https://doi.org/10.5194/acp-21-11053-2021, 2021
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Jianing Dai and Tao Wang
Atmos. Chem. Phys., 21, 8747–8759, https://doi.org/10.5194/acp-21-8747-2021, https://doi.org/10.5194/acp-21-8747-2021, 2021
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Yuting Wang, Yong-Feng Ma, Domingo Muñoz-Esparza, Cathy W. Y. Li, Mary Barth, Tao Wang, and Guy P. Brasseur
Atmos. Chem. Phys., 21, 3531–3553, https://doi.org/10.5194/acp-21-3531-2021, https://doi.org/10.5194/acp-21-3531-2021, 2021
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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.
Jiarong Li, Chao Zhu, Hui Chen, Defeng Zhao, Likun Xue, Xinfeng Wang, Hongyong Li, Pengfei Liu, Junfeng Liu, Chenglong Zhang, Yujing Mu, Wenjin Zhang, Luming Zhang, Hartmut Herrmann, Kai Li, Min Liu, and Jianmin Chen
Atmos. Chem. Phys., 20, 13735–13751, https://doi.org/10.5194/acp-20-13735-2020, https://doi.org/10.5194/acp-20-13735-2020, 2020
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Based on a field study at Mt. Tai, China, the simultaneous variations of cloud microphysics, aerosol microphysics and their potential interactions during cloud life cycles were discussed. Results demonstrated that clouds on clean days were more susceptible to the concentrations of particle number, while clouds formed on polluted days might be more sensitive to meteorological parameters. Particles larger than 150 nm played important roles in forming cloud droplets with sizes of 5–10 μm.
Ying Jiang, Likun Xue, Rongrong Gu, Mengwei Jia, Yingnan Zhang, Liang Wen, Penggang Zheng, Tianshu Chen, Hongyong Li, Ye Shan, Yong Zhao, Zhaoxin Guo, Yujian Bi, Hengde Liu, Aijun Ding, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 20, 12115–12131, https://doi.org/10.5194/acp-20-12115-2020, https://doi.org/10.5194/acp-20-12115-2020, 2020
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We analyzed the characteristics and sources of HONO in the upper boundary layer and lower free troposphere in the North China Plain, based on the field measurements at Mount Tai. Higher-than-expected levels and broad daytime peaks of HONO were observed. Without presence of ground surfaces, aerosol surface plays a key role in the heterogeneous HONO formation at high altitudes. Models without additional HONO sources largely
underestimatedthe oxidation processes in the elevation atmospheres.
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.
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.
Tianshu Chen, Likun Xue, Penggang Zheng, Yingnan Zhang, Yuhong Liu, Jingjing Sun, Guangxuan Han, Hongyong Li, Xin Zhang, Yunfeng Li, Hong Li, Can Dong, Fei Xu, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 20, 7069–7086, https://doi.org/10.5194/acp-20-7069-2020, https://doi.org/10.5194/acp-20-7069-2020, 2020
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Oil production is a significant source of ambient VOCs, but its impact on air quality has long been overlooked in China. We addressed this gap by conducting field campaigns in an oil field region followed by chemical modeling analyses. The VOC speciation profiles from the oil field emissions were directly measured for the first time in China. This study emphasizes the importance of oil extraction to photochemical pollution and atmospheric chemistry in the oil production regions of China.
Yanhong Zhu, Andreas Tilgner, Erik Hans Hoffmann, Hartmut Herrmann, Kimitaka Kawamura, Lingxiao Yang, Likun Xue, and Wenxing Wang
Atmos. Chem. Phys., 20, 6725–6747, https://doi.org/10.5194/acp-20-6725-2020, https://doi.org/10.5194/acp-20-6725-2020, 2020
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The formation and processing of secondary inorganic and organic compounds at Mt. Tai, the highest mountain on the North China Plain, are modeled using a multiphase chemical model. The concentrations of key radical and non-radical oxidations in the formation processes are investigated. Sensitivity tests assess the impacts of emission data and glyoxal partitioning constants on modeled results. The key precursors of secondary organic compounds are also identified.
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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Surface ozone levels in urban areas of China were increasing despite the implementation of stringent emission control measures since 2013. Our modeling results show that the decrease in NOx, SO2, and PM emissions and increase in VOC emissions contributed to the urban ozone increases due to the nonlinear ozone chemistry and complex aerosol affects. VOC reduction measures should be implemented in the current and future policies to achieve the goal of improving the overall air quality.
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.
Gen Zhang, Honghui Xu, Hongli Wang, Likun Xue, Jianjun He, Wanyun Xu, Bing Qi, Rongguang Du, Chang Liu, Zeyuan Li, Ke Gui, Wanting Jiang, Linlin Liang, Yan Yan, and Xiaoyan Meng
Atmos. Chem. Phys., 20, 5391–5403, https://doi.org/10.5194/acp-20-5391-2020, https://doi.org/10.5194/acp-20-5391-2020, 2020
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.
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.
Jun Zhang, Xinfeng Wang, Rui Li, Shuwei Dong, Yingnan Zhang, Penggang Zheng, Min Li, Tianshu Chen, Yuhong Liu, Likun Xue, Wei Nie, Aijun Ding, Mingjin Tang, Xuehua Zhou, Lin Du, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-757, https://doi.org/10.5194/acp-2019-757, 2019
Preprint withdrawn
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This study presents the concentrations, variation characteristics, and key influencing factors of particulate organic nitrates at four urban and rural sites in eastern China. The effects of anthropogenic activities (i.e. biomass burning and coal combustion) and meteorological conditions (in particular the humidity) on the secondary formation of organic nitrates have been investigated. The results highlight the greater role of SO2 in organic nitrate chemistry than previously assumed.
Siyang Li, Xiaotong Jiang, Marie Roveretto, Christian George, Ling Liu, Wei Jiang, Qingzhu Zhang, Wenxing Wang, Maofa Ge, and Lin Du
Atmos. Chem. Phys., 19, 9887–9902, https://doi.org/10.5194/acp-19-9887-2019, https://doi.org/10.5194/acp-19-9887-2019, 2019
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We stimulated the photochemical aging of organic film coated on aqueous aerosol in the presence of imidazole-2-carboxaldehyde, humic acid, an atmospheric PM2.5 sample, and a secondary organic aerosol sample from the lab. The unsaturated lipid mixed with photosensitizer under UV irradiation produced hydroperoxides, leading to surface area increase in organic film. Our results reveal the modification of organic film on aqueous aerosol has potential influence on the hygroscopic growth of droplets.
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
Xiaopu Lyu, Nan Wang, Hai Guo, Likun Xue, Fei Jiang, Yangzong Zeren, Hairong Cheng, Zhe Cai, Lihui Han, and Ying Zhou
Atmos. Chem. Phys., 19, 3025–3042, https://doi.org/10.5194/acp-19-3025-2019, https://doi.org/10.5194/acp-19-3025-2019, 2019
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Through analyses on the synoptic systems, pollution characteristics of O3 precursors, and modeling of local O3 formation and processes influencing O3 level, we found that this O3 pollution event was induced by a uniform pressure field over the Shandong Peninsula and also aggravated by a low-pressure trough in the last few days. This finding indicated that the NCP might be an O3 source region, which exported photochemical pollution to the adjoining regions or even to the neighboring countries.
Lei Sun, Likun Xue, Yuhang Wang, Longlei Li, Jintai Lin, Ruijing Ni, Yingying Yan, Lulu Chen, Juan Li, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 19, 1455–1469, https://doi.org/10.5194/acp-19-1455-2019, https://doi.org/10.5194/acp-19-1455-2019, 2019
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We quantified the detailed impacts of meteorology and anthropogenic emissions on surface O3 increase in central eastern China between 2003 and 2015 using GEOS-Chem. The emission change plays a more important role than the meteorological change, while the regions with a larger O3 increase are more sensitive to meteorology. NMVOC emission change dominated the O3 increase in eastern CEC, while NOx emission change led to an O3 increase in western and central CEC and O3 decrease in urban areas.
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.
Yanhong Zhu, Lingxiao Yang, Jianmin Chen, Kimitaka Kawamura, Mamiko Sato, Andreas Tilgner, Dominik van Pinxteren, Ying Chen, Likun Xue, Xinfeng Wang, Isobel J. Simpson, Hartmut Herrmann, Donald R. Blake, and Wenxing Wang
Atmos. Chem. Phys., 18, 10741–10758, https://doi.org/10.5194/acp-18-10741-2018, https://doi.org/10.5194/acp-18-10741-2018, 2018
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Molecular distributions of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls in the free troposphere are identified, and their concentration variations between 2014 and 2006 are presented. High nighttime concentrations were probably due to precursor emissions and aqueous-phase oxidation. Biomass burning was significant, but its tracer levoglucosan in 2014 was 5 times lower than 2006 concentrations. Finally, regional emission from anthropogenic activities was identified as a major source.
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.
Caihong Xu, Min Wei, Jianmin Chen, Chao Zhu, Jiarong Li, Ganglin Lv, Xianmang Xu, Lulu Zheng, Guodong Sui, Weijun Li, Bing Chen, Wenxing Wang, Qingzhu Zhang, Aijun Ding, and Abdelwahid Mellouki
Atmos. Chem. Phys., 17, 11247–11260, https://doi.org/10.5194/acp-17-11247-2017, https://doi.org/10.5194/acp-17-11247-2017, 2017
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Fungi are ubiquitous throughout the near-surface atmosphere, where they represent an important component of primary biological aerosol particles. The diversity and composition of the fungal communities varied over the different seasons between the fine (PM2.5) and submicron (PM1) particles at the summit of Mt. Tai located in the North China Plain, China. This work may serve as an important reference for the fungal contribution to primary biological aerosol particles.
Jiarong Li, Xinfeng Wang, Jianmin Chen, Chao Zhu, Weijun Li, Chengbao Li, Lu Liu, Caihong Xu, Liang Wen, Likun Xue, Wenxing Wang, Aijun Ding, and Hartmut Herrmann
Atmos. Chem. Phys., 17, 9885–9896, https://doi.org/10.5194/acp-17-9885-2017, https://doi.org/10.5194/acp-17-9885-2017, 2017
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Cloud events at Mt. Tai were investigated for the chemical composition and size distribution of cloud droplets. An obvious rise in pH was found for elevated NH+4 during the last decade. Higher PM2.5 levels resulted in higher concentrations of water-soluble ions, smaller sizes and higher numbers of cloud droplets. The mechanism of cloud-droplet formation and the mass transfer between aerosol–gas–cloud phases were summarized to enrich the knowledge of cloud chemical and microphysical properties.
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.
Min Wei, Caihong Xu, Jianmin Chen, Chao Zhu, Jiarong Li, and Ganglin Lv
Atmos. Chem. Phys., 17, 5253–5270, https://doi.org/10.5194/acp-17-5253-2017, https://doi.org/10.5194/acp-17-5253-2017, 2017
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Bacterial communities in cloud water collected at the summit of Mt Tai from 24 July to 23 August 2014 were investigated. A highly diverse bacterial community was retrieved. Community function prediction suggested that pathways related to metabolism and disease infections were significantly correlated with the predominant genera. Potential pathogens were enriched in the polluted cloud samples, whereas the diverse ecological function groups were significant in the non-polluted samples.
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.
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.
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.
Yi Zhu, Jiping Zhang, Junxia Wang, Wenyuan Chen, Yiqun Han, Chunxiang Ye, Yingruo Li, Jun Liu, Limin Zeng, Yusheng Wu, Xinfeng Wang, Wenxing Wang, Jianmin Chen, and Tong Zhu
Atmos. Chem. Phys., 16, 12551–12565, https://doi.org/10.5194/acp-16-12551-2016, https://doi.org/10.5194/acp-16-12551-2016, 2016
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With five repeated experiments using a mobile laboratory, we obtained the spatial distribution of major air pollutants over the surface of the North China Plain (NCP). All the pollutants were at high levels, with pollutant peak values in nearby major cities and along transport routes. With simulated wind fields, we identified the prevalent transport routes of air pollutants on different parts of the NCP, reflecting the transport of air pollution between megacities and surrounding regions.
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.
Xuezhe Xu, Weixiong Zhao, Qilei Zhang, Shuo Wang, Bo Fang, Weidong Chen, Dean S. Venables, Xinfeng Wang, Wei Pu, Xin Wang, Xiaoming Gao, and Weijun Zhang
Atmos. Chem. Phys., 16, 6421–6439, https://doi.org/10.5194/acp-16-6421-2016, https://doi.org/10.5194/acp-16-6421-2016, 2016
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We report on the field measurement of the optical properties and chemical composition of PM1.0 particles in a suburban environment in Beijing during the winter coal heating season. Organic mass was the largest contributor to the total extinction of PM1.0, while EC, owing to its high absorption efficiency, contributed appreciably to PM1.0 extinction and should be a key target to air quality controls. Non-BC absorption from secondary organic aerosol also contributes to particle absorption.
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: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
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Chemical composition, sources and formation mechanism of urban PM2.5 in Southwest China: a case study at the beginning of 2023
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Real-world observations of reduced nitrogen and ultrafine particles in commercial cooking organic aerosol emissions
Source apportionment of PM2.5 in Montréal, Canada, and health risk assessment for potentially toxic elements
Physicochemical and temporal characteristics of individual atmospheric aerosol particles in urban Seoul during KORUS-AQ campaign: insights from single-particle analysis
Mass spectrometric analysis of unprecedented high levels of carbonaceous aerosol particles long-range transported from wildfires in the Siberian Arctic
Short-term source apportionment of fine particulate matter with time-dependent profiles using SoFi Pro: exploring the reliability of rolling positive matrix factorization (PMF) applied to bihourly molecular and elemental tracer data
Particulate-bound alkyl nitrate pollution and formation mechanisms in Beijing, China
Non-negligible secondary contribution to brown carbon in autumn and winter: inspiration from particulate nitrated and oxygenated aromatic compounds in urban Beijing
Characterization of water-soluble brown carbon chromophores from wildfire plumes in the western USA using size-exclusion chromatography
Marine carbohydrates in Arctic aerosol particles and fog – diversity of oceanic sources and atmospheric transformations
Investigating the contribution of grown new particles to cloud condensation nuclei with largely varying preexisting particles – Part 1: Observational data analysis
Measurement report: Brown carbon aerosol in polluted urban air of the North China Plain – day–night differences in the chromophores and optical properties
Source apportionment of soot particles and aqueous-phase processing of black carbon coatings in an urban environment
Daytime and nighttime aerosol soluble iron formation in clean and slightly-polluted moisture air in a coastal city in eastern China
Impact of Weather Patterns and Meteorological Factors on PM2.5 and O3 during the Covid-19 Lockdown in China
Seasonal variations in composition and sources of atmospheric ultrafine particles in urban Beijing based on near-continuous measurements
Summertime response of ozone and fine particulate matter to mixing layer meteorology over the North China Plain
Trace elements in PM2.5 aerosols in East Asian outflow in the spring of 2018: emission, transport, and source apportionment
Measurement Report: Investigation on the sources and formation processes of dicarboxylic acids and related species in urban aerosols before and during the COVID-19 lockdown in Jinan, East China
pH dependence of brown-carbon optical properties in cloud water
Oxidative potential in rural, suburban and city centre atmospheric environments in central Europe
Secondary aerosol formation during a special dust transport event: impacts from unusually enhanced ozone and dust backflows over the ocean
Intra-event evolution of elemental and ionic concentrations in wet deposition in an urban environment
Spatial and diurnal variations of aerosol organosulfates in summertime Shanghai, China: potential influence of photochemical processes and anthropogenic sulfate pollution
Bayesian Inference-Based Estimation of Hourly Primary and Secondary Organic Carbon at Suburban Hong Kong: Multi-temporal Scale Variations and Evolution Characteristics during PM2.5 episodes
Simultaneous organic aerosol source apportionment at two Antarctic sites reveals large-scale and eco-region specific components
Characterizing water-soluble brown carbon in fine particles in four typical cities in northwestern China during wintertime: integrating optical properties with chemical processes
Chemical composition-dependent hygroscopic behavior of individual ambient aerosol particles collected at a coastal site
Gas–particle partitioning of semivolatile organic compounds when wildfire smoke comes to town
Enrichment of calcium in sea spray aerosol: insights from bulk measurements and individual particle analysis during the R/V Xuelong cruise in the summertime in Ross Sea, Antarctica
Source apportionment study on particulate air pollution in two high-altitude Bolivian cities: La Paz and El Alto
Morphological features and water solubility of iron in aged fine aerosol particles over the Indian Ocean
What chemical species are responsible for new particle formation and growth in the Netherlands? A hybrid positive matrix factorization (PMF) analysis using aerosol composition (ACSM) and size (SMPS)
Measurement report: Stoichiometry of dissolved iron and aluminum as an indicator of the factors controlling the fractional solubility of aerosol iron – results of the annual observations of size-fractionated aerosol particles in Japan
In-depth study of the formation processes of single atmospheric particles in the south-eastern margin of the Tibetan Plateau
Yi-Jia Ma, Yu Xu, Ting Yang, Hong-Wei Xiao, and Hua-Yun Xiao
Atmos. Chem. Phys., 24, 4331–4346, https://doi.org/10.5194/acp-24-4331-2024, https://doi.org/10.5194/acp-24-4331-2024, 2024
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This study provides field-based evidence about the differential impacts of combustion of fresh and aged biomass materials on aerosol nitrogen-containing organic compounds (NOCs) in different seasons in Ürümqi, bridging the linkages between the observations and previous laboratory studies showing the formation mechanisms of NOCs.
Maud Leriche, Pierre Tulet, Laurent Deguillaume, Frédéric Burnet, Aurélie Colomb, Agnès Borbon, Corinne Jambert, Valentin Duflot, Stéphan Houdier, Jean-Luc Jaffrezo, Mickaël Vaïtilingom, Pamela Dominutti, Manon Rocco, Camille Mouchel-Vallon, Samira El Gdachi, Maxence Brissy, Maroua Fathalli, Nicolas Maury, Bert Verreyken, Crist Amelynck, Niels Schoon, Valérie Gros, Jean-Marc Pichon, Mickael Ribeiro, Eric Pique, Emmanuel Leclerc, Thierry Bourrianne, Axel Roy, Eric Moulin, Joël Barrie, Jean-Marc Metzger, Guillaume Péris, Christian Guadagno, Chatrapatty Bhugwant, Jean-Mathieu Tibere, Arnaud Tournigand, Evelyn Freney, Karine Sellegri, Anne-Marie Delort, Pierre Amato, Muriel Joly, Jean-Luc Baray, Pascal Renard, Angelica Bianco, Anne Réchou, and Guillaume Payen
Atmos. Chem. Phys., 24, 4129–4155, https://doi.org/10.5194/acp-24-4129-2024, https://doi.org/10.5194/acp-24-4129-2024, 2024
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Aerosol particles in the atmosphere play a key role in climate change and air pollution. A large number of aerosol particles are formed from the oxidation of volatile organic compounds (VOCs and secondary organic aerosols – SOA). An important field campaign was organized on Réunion in March–April 2019 to understand the formation of SOA in a tropical atmosphere mostly influenced by VOCs emitted by forest and in the presence of clouds. This work synthesizes the results of this campaign.
Ryan N. Farley, James E. Lee, Laura-Hélèna Rivellini, Alex K. Y. Lee, Rachael Dal Porto, Christopher D. Cappa, Kyle Gorkowski, Abu Sayeed Md Shawon, Katherine B. Benedict, Allison C. Aiken, Manvendra K. Dubey, and Qi Zhang
Atmos. Chem. Phys., 24, 3953–3971, https://doi.org/10.5194/acp-24-3953-2024, https://doi.org/10.5194/acp-24-3953-2024, 2024
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The black carbon aerosol composition and mixing state were characterized using a soot particle aerosol mass spectrometer. Single-particle measurements revealed the major role of atmospheric processing in modulating the black carbon mixing state. A significant fraction of soot particles were internally mixed with oxidized organic aerosol and sulfate, with implications for activation as cloud nuclei.
Xinya Liu, Bas Henzing, Arjan Hensen, Jan Mulder, Peng Yao, Danielle van Dinther, Jerry van Bronckhorst, Rujin Huang, and Ulrike Dusek
Atmos. Chem. Phys., 24, 3405–3420, https://doi.org/10.5194/acp-24-3405-2024, https://doi.org/10.5194/acp-24-3405-2024, 2024
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We evaluated the time-of-flight aerosol chemical speciation monitor (TOF-ACSM) following the implementation of the PM2.5 aerodynamic lens and a capture vaporizer (CV). The results showed that it significantly improved the accuracy and precision of ACSM in the field observations. The paper elucidates the measurement outcomes of various instruments and provides an analysis of their biases. This comprehensive evaluation is expected to benefit the ACSM community and other aerosol field measurements.
Eva-Lou Edwards, Yonghoon Choi, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Claire E. Robinson, Michael A. Shook, Edward L. Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 24, 3349–3378, https://doi.org/10.5194/acp-24-3349-2024, https://doi.org/10.5194/acp-24-3349-2024, 2024
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We investigate Cl− depletion in sea salt particles over the northwest Atlantic from December 2021 to June 2022 using an airborne dataset. Losses of Cl− are greatest in May and least in December–February and March. Inorganic acidic species can account for all depletion observed for December–February, March, and June near Bermuda but none in May. Quantifying Cl− depletion as a percentage captures seasonal trends in depletion but fails to convey the effects it may have on atmospheric oxidation.
Yue Sun, Yujiao Zhu, Yanbin Qi, Lanxiadi Chen, Jiangshan Mu, Ye Shan, Yu Yang, Yanqiu Nie, Ping Liu, Can Cui, Ji Zhang, Mingxuan Liu, Lingli Zhang, Yufei Wang, Xinfeng Wang, Mingjin Tang, Wenxing Wang, and Likun Xue
Atmos. Chem. Phys., 24, 3241–3256, https://doi.org/10.5194/acp-24-3241-2024, https://doi.org/10.5194/acp-24-3241-2024, 2024
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Field observations were conducted at the summit of Changbai Mountain in northeast Asia. The cumulative number concentration of ice-nucleating particles (INPs) varied from 1.6 × 10−3 to 78.3 L−1 over the temperature range of −5.5 to −29.0 ℃. Biological INPs (bio-INPs) accounted for the majority of INPs, and the proportion exceeded 90% above −13.0 ℃. Planetary boundary layer height, valley breezes, and long-distance transport of air mass influence the abundance of bio-INPs.
Cuizhi Sun, Yongyun Zhang, Baoling Liang, Min Gao, Xi Sun, Fei Li, Xue Ni, Qibin Sun, Hengjia Ou, Dexian Chen, Shengzhen Zhou, and Jun Zhao
Atmos. Chem. Phys., 24, 3043–3063, https://doi.org/10.5194/acp-24-3043-2024, https://doi.org/10.5194/acp-24-3043-2024, 2024
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In a May–June 2021 expedition in the South China Sea, we analyzed black and brown carbon in marine aerosols, key to light absorption and climate impact. Using advanced in situ and microscope techniques, we observed particle size, structure, and tar balls mixed with various elements. Results showed biomass burning and fossil fuels majorly influence light absorption, especially during significant burning events. This research aids the understanding of carbonaceous aerosols' role in marine climate.
C. Isabel Moreno, Radovan Krejci, Jean-Luc Jaffrezo, Gaëlle Uzu, Andrés Alastuey, Marcos F. Andrade, Valeria Mardóñez, Alkuin Maximilian Koenig, Diego Aliaga, Claudia Mohr, Laura Ticona, Fernando Velarde, Luis Blacutt, Ricardo Forno, David N. Whiteman, Alfred Wiedensohler, Patrick Ginot, and Paolo Laj
Atmos. Chem. Phys., 24, 2837–2860, https://doi.org/10.5194/acp-24-2837-2024, https://doi.org/10.5194/acp-24-2837-2024, 2024
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Aerosol chemical composition (ions, sugars, carbonaceous matter) from 2011 to 2020 was studied at Mt. Chacaltaya (5380 m a.s.l., Bolivian Andes). Minimum concentrations occur in the rainy season with maxima in the dry and transition seasons. The origins of the aerosol are located in a radius of hundreds of kilometers: nearby urban and rural areas, natural biogenic emissions, vegetation burning from Amazonia and Chaco, Pacific Ocean emissions, soil dust, and Peruvian volcanism.
Junke Zhang, Yunfei Su, Chunying Chen, Wenkai Guo, Qinwen Tan, Miao Feng, Danlin Song, Tao Jiang, Qiang Chen, Yuan Li, Wei Li, Yizhi Wang, Xiaojuan Huang, Lin Han, Wanqing Wu, and Gehui Wang
Atmos. Chem. Phys., 24, 2803–2820, https://doi.org/10.5194/acp-24-2803-2024, https://doi.org/10.5194/acp-24-2803-2024, 2024
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Typical haze events in Chengdu at the beginning of 2023 were investigated with bulk-chemical and single-particle analyses along with numerical model simulations. By integrating the obtained chemical composition, source, mixing state and numerical simulation results, we infer that Haze-1 was mainly caused by pollutants related to fossil fuel combustion, especially local mobile sources, while Haze-2 was triggered by the secondary pollutants, which mainly came from regional transmission.
Elena Barbaro, Matteo Feltracco, Fabrizio De Blasi, Clara Turetta, Marta Radaelli, Warren Cairns, Giulio Cozzi, Giovanna Mazzi, Marco Casula, Jacopo Gabrieli, Carlo Barbante, and Andrea Gambaro
Atmos. Chem. Phys., 24, 2821–2835, https://doi.org/10.5194/acp-24-2821-2024, https://doi.org/10.5194/acp-24-2821-2024, 2024
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The study analyzed a year of atmospheric aerosol composition at Col Margherita in the Italian Alps. Over 100 chemical markers were identified, including major ions, organic compounds, and trace elements. It revealed sources of aerosol, highlighted impacts of Saharan dust events, and showed anthropogenic pollution's influence despite the site's remoteness. Enrichment factors emphasized non-natural sources of trace elements. Source apportionment identified four key factors affecting the area.
Karl Espen Yttri, Are Bäcklund, Franz Conen, Sabine Eckhardt, Nikolaos Evangeliou, Markus Fiebig, Anne Kasper-Giebl, Avram Gold, Hans Gundersen, Cathrine Lund Myhre, Stephen Matthew Platt, David Simpson, Jason D. Surratt, Sönke Szidat, Martin Rauber, Kjetil Tørseth, Martin Album Ytre-Eide, Zhenfa Zhang, and Wenche Aas
Atmos. Chem. Phys., 24, 2731–2758, https://doi.org/10.5194/acp-24-2731-2024, https://doi.org/10.5194/acp-24-2731-2024, 2024
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We discuss carbonaceous aerosol (CA) observed at the high Arctic Zeppelin Observatory (2017 to 2020). We find that organic aerosol is a significant fraction of the Arctic aerosol, though less than sea salt aerosol and mineral dust, as well as non-sea-salt sulfate, originating mainly from anthropogenic sources in winter and from natural sources in summer, emphasizing the importance of wildfires for biogenic secondary organic aerosol and primary biological aerosol particles observed in the Arctic.
Wei Huang, Cheng Wu, Linyu Gao, Yvette Gramlich, Sophie L. Haslett, Joel Thornton, Felipe D. Lopez-Hilfiker, Ben H. Lee, Junwei Song, Harald Saathoff, Xiaoli Shen, Ramakrishna Ramisetty, Sachchida N. Tripathi, Dilip Ganguly, Feng Jiang, Magdalena Vallon, Siegfried Schobesberger, Taina Yli-Juuti, and Claudia Mohr
Atmos. Chem. Phys., 24, 2607–2624, https://doi.org/10.5194/acp-24-2607-2024, https://doi.org/10.5194/acp-24-2607-2024, 2024
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We present distinct molecular composition and volatility of oxygenated organic aerosol particles in different rural, urban, and mountain environments. We do a comprehensive investigation of the relationship between the chemical composition and volatility of oxygenated organic aerosol particles across different systems and environments. This study provides implications for volatility descriptions of oxygenated organic aerosol particles in different model frameworks.
Jing Cai, Juha Sulo, Yifang Gu, Sebastian Holm, Runlong Cai, Steven Thomas, Almuth Neuberger, Fredrik Mattsson, Marco Paglione, Stefano Decesari, Matteo Rinaldi, Rujing Yin, Diego Aliaga, Wei Huang, Yuanyuan Li, Yvette Gramlich, Giancarlo Ciarelli, Lauriane Quéléver, Nina Sarnela, Katrianne Lehtipalo, Nora Zannoni, Cheng Wu, Wei Nie, Juha Kangasluoma, Claudia Mohr, Markku Kulmala, Qiaozhi Zha, Dominik Stolzenburg, and Federico Bianchi
Atmos. Chem. Phys., 24, 2423–2441, https://doi.org/10.5194/acp-24-2423-2024, https://doi.org/10.5194/acp-24-2423-2024, 2024
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By combining field measurements, simulations and recent chamber experiments, we investigate new particle formation (NPF) and growth in the Po Valley, where both haze and frequent NPF occur. Our results show that sulfuric acid, ammonia and amines are the dominant NPF precursors there. A high NPF rate and a lower condensation sink lead to a greater survival probability for newly formed particles, highlighting the importance of gas-to-particle conversion for aerosol concentrations.
Kaori Kawana, Fumikazu Taketani, Kazuhiko Matsumoto, Yutaka Tobo, Yoko Iwamoto, Takuma Miyakawa, Akinori Ito, and Yugo Kanaya
Atmos. Chem. Phys., 24, 1777–1799, https://doi.org/10.5194/acp-24-1777-2024, https://doi.org/10.5194/acp-24-1777-2024, 2024
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Based on comprehensive shipborne observations, we found strong links between sea-surface biological materials and the formation of atmospheric fluorescent bioaerosols, cloud condensation nuclei, and ice-nucleating particles over the Arctic Ocean and Bering Sea during autumn 2019. Taking the wind-speed effect into account, we propose equations to approximate the links for this cruise, which can be used as a guide for modeling as well as for systematic comparisons with other observations.
Chen He, Hanxiong Che, Zier Bao, Yiliang Liu, Qing Li, Miao Hu, Jiawei Zhou, Shumin Zhang, Xiaojiang Yao, Quan Shi, Chunmao Chen, Yan Han, Lingshuo Meng, Xin Long, Fumo Yang, and Yang Chen
Atmos. Chem. Phys., 24, 1627–1639, https://doi.org/10.5194/acp-24-1627-2024, https://doi.org/10.5194/acp-24-1627-2024, 2024
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We examined the daily evolution of high molecular-weight organic compounds with a molecular weight of up to 1000 Da in order to comprehend their behaviors in the atmosphere under actual conditions. These compounds were proven to undergo multi-generation oxidation, carboxylation, and nitrification via both day- and nighttime chemistry.
Karine Desboeufs, Paola Formenti, Raquel Torres-Sánchez, Kerstin Schepanski, Jean-Pierre Chaboureau, Hendrik Andersen, Jan Cermak, Stefanie Feuerstein, Benoit Laurent, Danitza Klopper, Andreas Namwoonde, Mathieu Cazaunau, Servanne Chevaillier, Anaïs Feron, Cécile Mirande-Bret, Sylvain Triquet, and Stuart J. Piketh
Atmos. Chem. Phys., 24, 1525–1541, https://doi.org/10.5194/acp-24-1525-2024, https://doi.org/10.5194/acp-24-1525-2024, 2024
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This study investigates the fractional solubility of iron (Fe) in dust particles along the coast of Namibia, a critical region for the atmospheric Fe supply of the South Atlantic Ocean. Our results suggest a possible two-way interplay whereby marine biogenic emissions from the coastal marine ecosystems into the atmosphere would increase the solubility of Fe-bearing dust by photo-reduction processes. The subsequent deposition of soluble Fe could act to further enhance marine biogenic emissions.
Sunhye Kim, Jo Machesky, Drew R. Gentner, and Albert A. Presto
Atmos. Chem. Phys., 24, 1281–1298, https://doi.org/10.5194/acp-24-1281-2024, https://doi.org/10.5194/acp-24-1281-2024, 2024
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Cooking emissions are often an overlooked source of air pollution. We used a mobile lab to measure the characteristics of particles emitted from cooking sites in two cities. Our findings showed that cooking releases a substantial number of fine particles. While most emissions were similar, a bakery site showed distinctive chemical compositions with higher nitrogen compound levels. Thus, understanding the particle emissions from different cooking activities is crucial.
Nansi Fakhri, Robin Stevens, Arnold Downey, Konstantina Oikonomou, Jean Sciare, Charbel Afif, and Patrick L. Hayes
Atmos. Chem. Phys., 24, 1193–1212, https://doi.org/10.5194/acp-24-1193-2024, https://doi.org/10.5194/acp-24-1193-2024, 2024
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We investigated the chemical composition of atmospheric fine particles, their emission sources, and the potential human health risk associated with trace elements in particles for an urban site in Montréal over a 3-month period (August–November). This study represents the first time that such extensive composition measurements were included in an urban source apportionment study in Canada, and it provides greater resolution of fine-particle sources than has been previously achieved in Canada.
Hanjin Yoo, Li Wu, Hong Geng, and Chul-Un Ro
Atmos. Chem. Phys., 24, 853–867, https://doi.org/10.5194/acp-24-853-2024, https://doi.org/10.5194/acp-24-853-2024, 2024
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We conducted an investigation of atmospheric aerosols collected in Seoul, South Korea, during the KORUS-AQ campaign on a single-particle basis. We were able to identify their sources, the atmospheric fate, and the impacts of local emissions and long-range transport on aerosol composition. Additionally, we traced potential sources of non-exhaust heavy-metal particles. This comprehensive analysis provides valuable insights into the complex dynamics of urban aerosols.
Eric Schneider, Hendryk Czech, Olga Popovicheva, Marina Chichaeva, Vasily Kobelev, Nikolay Kasimov, Tatiana Minkina, Christopher Paul Rüger, and Ralf Zimmermann
Atmos. Chem. Phys., 24, 553–576, https://doi.org/10.5194/acp-24-553-2024, https://doi.org/10.5194/acp-24-553-2024, 2024
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This study provides insights into the complex chemical composition of long-range-transported wildfire plumes from Yakutia, which underwent different levels of atmospheric processing. With complementary mass spectrometric techniques, we improve our understanding of the chemical processes and atmospheric fate of wildfire plumes. Unprecedented high levels of carbonaceous aerosols crossed the polar circle with implications for the Arctic ecosystem and consequently climate.
Qiongqiong Wang, Shuhui Zhu, Shan Wang, Cheng Huang, Yusen Duan, and Jian Zhen Yu
Atmos. Chem. Phys., 24, 475–486, https://doi.org/10.5194/acp-24-475-2024, https://doi.org/10.5194/acp-24-475-2024, 2024
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We investigated short-term source apportionment of PM2.5 utilizing rolling positive matrix factorization (PMF) and online PM chemical speciation data, which included source-specific organic tracers collected over a period of 37 d during the winter of 2019–2020 in suburban Shanghai, China. The findings highlight that by imposing constraints on the primary source profiles, short-term PMF analysis successfully replicated both the individual primary sources and the total secondary sources.
Jiyuan Yang, Guoyang Lei, Jinfeng Zhu, Yutong Wu, Chang Liu, Kai Hu, Junsong Bao, Zitong Zhang, Weili Lin, and Jun Jin
Atmos. Chem. Phys., 24, 123–136, https://doi.org/10.5194/acp-24-123-2024, https://doi.org/10.5194/acp-24-123-2024, 2024
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The atmospheric pollution and formation mechanisms of particulate-bound alkyl nitrate in Beijing were studied. C9–C16 long-chain n-alkyl nitrates negatively correlated with O3 but positively correlated with PM2.5 and NO2, so they may not be produced during gas-phase homogeneous reactions in the photochemical process but form through reactions between alkanes and nitrates on PM surfaces. Particulate-bound n-alkyl nitrates strongly affect both haze pollution and atmospheric visibility.
Yanqin Ren, Zhenhai Wu, Yuanyuan Ji, Fang Bi, Junling Li, Haijie Zhang, Hao Zhang, Hong Li, and Gehui Wang
EGUsphere, https://doi.org/10.5194/egusphere-2023-2593, https://doi.org/10.5194/egusphere-2023-2593, 2024
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Nitrated aromatic compounds (NACs) and oxygenated derivatives of polycyclic aromatic hydrocarbons (OPAHs) in PM2.5 were examined from an urban area in Beijing during the autumn and winter. The OPAHs and NACs concentrations were much higher during heating than those before heating. They majorly originated from the combustion of biomass and automobile emissions, and the secondary generation was the major contributor throughout the whole sampling period.
Lisa Azzarello, Rebecca A. Washenfelder, Michael A. Robinson, Alessandro Franchin, Caroline C. Womack, Christopher D. Holmes, Steven S. Brown, Ann Middlebrook, Tim Newberger, Colm Sweeney, and Cora J. Young
Atmos. Chem. Phys., 23, 15643–15654, https://doi.org/10.5194/acp-23-15643-2023, https://doi.org/10.5194/acp-23-15643-2023, 2023
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We present a molecular size-resolved offline analysis of water-soluble brown carbon collected on an aircraft during FIREX-AQ. The smoke plumes were aged 0 to 5 h, where absorption was dominated by small molecular weight molecules, brown carbon absorption downwind did not consistently decrease, and the measurements differed from online absorption measurements of the same samples. We show how differences between online and offline absorption could be related to different measurement conditions.
Sebastian Zeppenfeld, Manuela van Pinxteren, Markus Hartmann, Moritz Zeising, Astrid Bracher, and Hartmut Herrmann
Atmos. Chem. Phys., 23, 15561–15587, https://doi.org/10.5194/acp-23-15561-2023, https://doi.org/10.5194/acp-23-15561-2023, 2023
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Marine carbohydrates are produced in the surface of the ocean, enter the atmophere as part of sea spray aerosol particles, and potentially contribute to the formation of fog and clouds. Here, we present the results of a sea–air transfer study of marine carbohydrates conducted in the high Arctic. Besides a chemo-selective transfer, we observed a quick atmospheric aging of carbohydrates, possibly as a result of both biotic and abiotic processes.
Xing Wei, Yanjie Shen, Xiao-Ying Yu, Yang Gao, Huiwang Gao, Ming Chu, Yujiao Zhu, and Xiaohong Yao
Atmos. Chem. Phys., 23, 15325–15350, https://doi.org/10.5194/acp-23-15325-2023, https://doi.org/10.5194/acp-23-15325-2023, 2023
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We investigate the contribution of grown new particles to Nccn at a rural mountain site in the North China Plain. The total particle number concentrations (Ncn) observed on 8 new particle formation (NPF) days were higher compared to non-NPF days. The Nccn at 0.2 % supersaturation (SS) and 0.4 % SS on the NPF days was significantly lower than on non-NPF days. Only one of eight NPF events had detectable net contributions to Nccn at 0.4 % SS and 1.0 % SS with increased κ values.
Yuquan Gong, Ru-Jin Huang, Lu Yang, Ting Wang, Wei Yuan, Wei Xu, Wenjuan Cao, Yang Wang, and Yongjie Li
Atmos. Chem. Phys., 23, 15197–15207, https://doi.org/10.5194/acp-23-15197-2023, https://doi.org/10.5194/acp-23-15197-2023, 2023
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This study reveals the large day–night differences in brown carbon (BrC) chromophore composition, which was not known previously. The results provide insights into the effects of atmospheric processes and emissions on BrC composition.
Ryan N. Farley, Sonya Collier, Christopher D. Cappa, Leah R. Williams, Timothy B. Onasch, Lynn M. Russell, Hwajin Kim, and Qi Zhang
Atmos. Chem. Phys., 23, 15039–15056, https://doi.org/10.5194/acp-23-15039-2023, https://doi.org/10.5194/acp-23-15039-2023, 2023
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Soot particles, also known as black carbon (BC), have important implications for global climate and regional air quality. After the particles are emitted, BC can be coated with other material, impacting the aerosol properties. We selectively measured the composition of particles containing BC to explore their sources and chemical transformations in the atmosphere. We focus on a persistent, multiday fog event in order to study the effects of chemical reactions occurring within liquid droplets.
Wenshuai Li, Yuxuan Qi, Yingchen Liu, Guanru Wu, Yanjing Zhang, Jinhui Shi, Wenjun Qu, Lifang Sheng, Wencai Wang, Daizhou Zhang, and Yang Zhou
EGUsphere, https://doi.org/10.5194/egusphere-2023-2698, https://doi.org/10.5194/egusphere-2023-2698, 2023
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Aerosol particles from mainland can transport to oceans and deposit, providing soluble Fe and affecting phytoplankton growth. Thus, we studied the dissolution process of aerosol Fe and found that photochemistry played a key role in promoting Fe dissolution in clean conditions. RH-dependent reactions were more influential in slightly-polluted conditions. These results highlight the distinct roles of two weather-related parameters (radiation and RH) in influencing geochemical cycles related to Fe.
Fuzhen Shen, Michaela I. Hegglin, and Yue Yuan
EGUsphere, https://doi.org/10.5194/egusphere-2023-2425, https://doi.org/10.5194/egusphere-2023-2425, 2023
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We attempt to use a novel structural Self-Organising Map and Machine Learning models to identify a weather system and quantify the importance of each meteorological factor in driving the unexpected PM2.5 and O3 changes under the specific weather system during the COVID-19 lockdown in China. The result highlights temperature under the double-centre high-pressure system plays the most crucial role in abnormal events.
Xiaoxiao Li, Yijing Chen, Yuyang Li, Runlong Cai, Yiran Li, Chenjuan Deng, Jin Wu, Chao Yan, Hairong Cheng, Yongchun Liu, Markku Kulmala, Jiming Hao, James N. Smith, and Jingkun Jiang
Atmos. Chem. Phys., 23, 14801–14812, https://doi.org/10.5194/acp-23-14801-2023, https://doi.org/10.5194/acp-23-14801-2023, 2023
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Near-continuous measurements show the composition, sources, and seasonal variations of ultrafine particles (UFPs) in urban Beijing. Vehicle and cooking emissions and new particle formation are the main sources of UFPs, and aqueous/heterogeneous processes increase UFP mode diameters. UFPs are the highest in winter due to the highest primary particle emission rates and new particle formation rates, and CHO fractions are the highest in summer due to the strongest photooxidation.
Jiaqi Wang, Jian Gao, Fei Che, Xin Yang, Yuanqin Yang, Lei Liu, Yan Xiang, and Haisheng Li
Atmos. Chem. Phys., 23, 14715–14733, https://doi.org/10.5194/acp-23-14715-2023, https://doi.org/10.5194/acp-23-14715-2023, 2023
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Regional-scale observations of surface O3, PM2.5 and its major chemical species, mixing layer height (MLH), and other meteorological parameters were made in the North China Plain during summer. Unlike the cold season, synchronized increases in MDA8 O3 and PM2.5 under medium MLH conditions have been witnessed. The increasing trend of PM2.5 was associated with enhanced secondary chemical formation. The correlation between MLH and secondary air pollutants should be treated with care in hot seasons.
Takuma Miyakawa, Akinori Ito, Chunmao Zhu, Atsushi Shimizu, Erika Matsumoto, Yusuke Mizuno, and Yugo Kanaya
Atmos. Chem. Phys., 23, 14609–14626, https://doi.org/10.5194/acp-23-14609-2023, https://doi.org/10.5194/acp-23-14609-2023, 2023
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This study conducted semi-continuous measurements of PM2.5 aerosols and their elemental composition in western Japan, during spring 2018. It analyzed the emissions, transport, and wet removal of elements such as Pb, Cu, Fe, and Mn. It also assessed the accuracy of modeled concentrations and found overestimations of BC and underestimations of Cu and anthropogenic Fe in East Asia. Insights into emissions, removals, and source apportionment of trace metals in the East Asian outflow were provided.
Jingjing Meng, Yachen Wang, Yuanyuan Li, Tonglin Huang, Zhifei Wang, Yiqiu Wang, Min Chen, Zhanfang Hou, Houhua Zhou, Keding Lu, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 23, 14481–14503, https://doi.org/10.5194/acp-23-14481-2023, https://doi.org/10.5194/acp-23-14481-2023, 2023
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This study investigated the effect of COVID-19 lockdown (LCD) measures on the formation and evolutionary process of diacids and related compounds from field observations. Results demonstrate that more aged organic aerosols are observed during the LCD due to the enhanced photochemical oxidation. Our study also found that the reactivity of 13C was higher than that of 12C in the gaseous photochemical oxidation, leading to higher δ13C values of C2 during the LCD than before the LCD.
Christopher J. Hennigan, Michael McKee, Vikram Pratap, Bryanna Boegner, Jasper Reno, Lucia Garcia, Madison McLaren, and Sara M. Lance
Atmos. Chem. Phys., 23, 14437–14449, https://doi.org/10.5194/acp-23-14437-2023, https://doi.org/10.5194/acp-23-14437-2023, 2023
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This study characterized the optical properties of light-absorbing organic compounds, called brown carbon (BrC), in atmospheric cloud water samples. In all samples, light absorption by BrC increased linearly with increasing pH. There was variability in the sensitivity of the absorption–pH relationship, depending on the degree of influence from fire emissions. Overall, these results show that the climate forcing of BrC is quite strongly affected by its pH-dependent absorption.
Máté Vörösmarty, Gaëlle Uzu, Jean-Luc Jaffrezo, Pamela Dominutti, Zsófia Kertész, Enikő Papp, and Imre Salma
Atmos. Chem. Phys., 23, 14255–14269, https://doi.org/10.5194/acp-23-14255-2023, https://doi.org/10.5194/acp-23-14255-2023, 2023
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Poor air quality caused by high concentrations of particulate matter is one of the most severe public health concerns for humans worldwide. One of the most important biological mechanisms inducing adverse health effects is the oxidant–antioxidant imbalance. We showed that the oxidative stress changed substantially and in a complex manner with location and season. Biomass burning exhibited the dominant influence, while motor vehicles played an important role in the non-heating period.
Da Lu, Hao Li, Mengke Tian, Guochen Wang, Xiaofei Qin, Na Zhao, Juntao Huo, Fan Yang, Yanfen Lin, Jia Chen, Qingyan Fu, Yusen Duan, Xinyi Dong, Congrui Deng, Sabur F. Abdullaev, and Kan Huang
Atmos. Chem. Phys., 23, 13853–13868, https://doi.org/10.5194/acp-23-13853-2023, https://doi.org/10.5194/acp-23-13853-2023, 2023
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Environmental conditions during dust are usually not favorable for secondary aerosol formation. However in this study, an unusual dust event was captured in a Chinese mega-city and showed “anomalous” meteorology and a special dust backflow transport pathway. The underlying formation mechanisms of secondary aerosols are probed in the context of this special dust event. This study shows significant implications for the varying dust aerosol chemistry in the future changing climate.
Thomas Audoux, Benoit Laurent, Karine Desboeufs, Gael Noyalet, Franck Maisonneuve, Olivier Lauret, and Servanne Chevaillier
Atmos. Chem. Phys., 23, 13485–13503, https://doi.org/10.5194/acp-23-13485-2023, https://doi.org/10.5194/acp-23-13485-2023, 2023
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In the Paris region, a campaign was conducted to study wet deposition of aerosol particles during rainfall events. Simultaneous measurements of aerosol and wet deposition allowed us to discuss their transfer from the atmosphere to rain. Chemical evolution within events revealed meteorology, atmospheric conditions and local vs. long range sources as key factors. This study highlights the variability of wet deposition and the need to consider event-specific factors to understand its mechanisms.
Ting Yang, Yu Xu, Qing Ye, Yi-Jia Ma, Yu-Chen Wang, Jian-Zhen Yu, Yu-Sen Duan, Chen-Xi Li, Hong-Wei Xiao, Zi-Yue Li, Yue Zhao, and Hua-Yun Xiao
Atmos. Chem. Phys., 23, 13433–13450, https://doi.org/10.5194/acp-23-13433-2023, https://doi.org/10.5194/acp-23-13433-2023, 2023
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In this study, 130 OS species were quantified in ambient fine particulate matter (PM2.5) collected in urban and suburban Shanghai (East China) in the summer of 2021. The daytime OS formation was concretized based on the interactions among OSs, ultraviolet (UV), ozone (O3), and sulfate. Our finding provides field evidence for the influence of photochemical process and anthropogenic sulfate on OS formation and has important implications for the mitigation of organic particulate pollution.
Shan Wang, Kezheng Liao, Zijing Zhang, Yuk Ying Cheng, Qiongqiong Wang, Hanzhe Chen, and Jian Zhen Yu
EGUsphere, https://doi.org/10.5194/egusphere-2023-2286, https://doi.org/10.5194/egusphere-2023-2286, 2023
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In this work, hourly primary and secondary organic carbon were estimated by a novel Bayesian inference approach in suburban Hong Kong. Their multi-temporal scale variations and evolution characteristics during PM2.5 episodes were examined. The methodology could serve as a guide for other locations with similar monitoring capabilities. The observation-based results are helpful for understanding the evolving nature of secondary organic aerosols and refining the accuracy of model simulations.
Marco Paglione, David C. S. Beddows, Anna Jones, Thomas Lachlan-Cope, Matteo Rinaldi, Stefano Decesari, Francesco Manarini, Mara Russo, Karam Mansour, Roy M. Harrison, Andrea Mazzanti, Emilio Tagliavini, and Manuel Dall'Osto
EGUsphere, https://doi.org/10.5194/egusphere-2023-2275, https://doi.org/10.5194/egusphere-2023-2275, 2023
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Applying factor analysis techniques to H-NMR spectra, we present the Organic Aerosol (OA) source apportionment of PM1 samples collected in parallel at two peri-Antarctic stations, namely Signy and Halley, important to investigate aerosol-climate interactions in an unperturbed atmosphere. Our results show remarkable differences between pelagic (open ocean) and sympagic (sea-ice influenced) air masses and indicate that various sources and processes are controlling Antarctic aerosols.
Miao Zhong, Jianzhong Xu, Huiqin Wang, Li Gao, Haixia Zhu, Lixiang Zhai, Xinghua Zhang, and Wenhui Zhao
Atmos. Chem. Phys., 23, 12609–12630, https://doi.org/10.5194/acp-23-12609-2023, https://doi.org/10.5194/acp-23-12609-2023, 2023
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This study focus on coal-combustion-dominated aerosol in urban areas in northwestern China and combines the results of optical measurement and chemical analysis to deduce the evolution of these characteristics in the atmosphere, which has previously been unknown. The results provide insights into the effects of atmospheric processes and emissions on brown carbon properties.
Li Wu, Hyo-Jin Eom, Hanjin Yoo, Dhrubajyoti Gupta, Hye-Rin Cho, Pingqing Fu, and Chul-Un Ro
Atmos. Chem. Phys., 23, 12571–12588, https://doi.org/10.5194/acp-23-12571-2023, https://doi.org/10.5194/acp-23-12571-2023, 2023
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Hygroscopicity of ambient marine aerosols is of critical relevance to investigate their atmospheric impacts, which, however, remain uncertain due to their complex compositions and mixing states. Therefore, a study on the hygroscopic behavior of ambient marine aerosols for understanding the phase states when interacting with water vapor at different RH levels and their subsequent impacts on the heterogeneous chemical reactions, atmospheric environment, and human health is of vital importance.
Yutong Liang, Rebecca A. Wernis, Kasper Kristensen, Nathan M. Kreisberg, Philip L. Croteau, Scott C. Herndon, Arthur W. H. Chan, Nga L. Ng, and Allen H. Goldstein
Atmos. Chem. Phys., 23, 12441–12454, https://doi.org/10.5194/acp-23-12441-2023, https://doi.org/10.5194/acp-23-12441-2023, 2023
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We measured the gas–particle partitioning behaviors of biomass burning markers and examined the effect of wildfire organic aerosol on the partitioning of semivolatile organic compounds. Most compounds measured are less volatile than model predictions. Wildfire aerosol enhanced the condensation of polar compounds and caused some nonpolar (e.g., polycyclic aromatic hydrocarbons) compounds to partition into the gas phase, thus affecting their lifetimes in the atmosphere and the mode of exposure.
Bojiang Su, Xinhui Bi, Zhou Zhang, Yue Liang, Congbo Song, Tao Wang, Yaohao Hu, Lei Li, Zhen Zhou, Jinpei Yan, Xinming Wang, and Guohua Zhang
Atmos. Chem. Phys., 23, 10697–10711, https://doi.org/10.5194/acp-23-10697-2023, https://doi.org/10.5194/acp-23-10697-2023, 2023
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During the R/V Xuelong cruise observation over the Ross Sea, Antarctica, the mass concentrations of water-soluble Ca2+ and the mass spectra of individual calcareous particles were measured. Our results indicated that lower temperature, lower wind speed, and the presence of sea ice may facilitate Ca2+ enrichment in sea spray aerosols and highlighted the potential contribution of organically complexed calcium to calcium enrichment, which is inaccurate based solely on water-soluble Ca2+ estimation.
Valeria Mardoñez, Marco Pandolfi, Lucille Joanna S. Borlaza, Jean-Luc Jaffrezo, Andrés Alastuey, Jean-Luc Besombes, Isabel Moreno R., Noemi Perez, Griša Močnik, Patrick Ginot, Radovan Krejci, Vladislav Chrastny, Alfred Wiedensohler, Paolo Laj, Marcos Andrade, and Gaëlle Uzu
Atmos. Chem. Phys., 23, 10325–10347, https://doi.org/10.5194/acp-23-10325-2023, https://doi.org/10.5194/acp-23-10325-2023, 2023
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La Paz and El Alto are two fast-growing, high-altitude Bolivian cities forming the second-largest metropolitan area in the country. The sources of particulate matter (PM) in this conurbation were not previously investigated. This study identified 11 main sources of PM, of which dust and vehicular emissions stand out as the main ones. The influence of regional biomass combustion and local waste combustion was also observed, with the latter being a major source of hazardous compounds.
Sayako Ueda, Yoko Iwamoto, Fumikazu Taketani, Mingxu Liu, and Hitoshi Matsui
Atmos. Chem. Phys., 23, 10117–10135, https://doi.org/10.5194/acp-23-10117-2023, https://doi.org/10.5194/acp-23-10117-2023, 2023
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We examine iron in atmospheric fine aerosol particles collected over the Indian Ocean during shipborne observations in November 2018. Transmission electron microscopy analysis with water dialysis shows that various types of iron (fly ash, iron oxide, and mineral dust) co-exist with ammonium sulfate and that their solubility differs depending on the iron type. Using PM2.5 bulk samples and global model simulations, we elucidate their origins, aging, and implications for present iron simulations.
Farhan R. Nursanto, Roy Meinen, Rupert Holzinger, Maarten C. Krol, Xinya Liu, Ulrike Dusek, Bas Henzing, and Juliane L. Fry
Atmos. Chem. Phys., 23, 10015–10034, https://doi.org/10.5194/acp-23-10015-2023, https://doi.org/10.5194/acp-23-10015-2023, 2023
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Particulate matter (PM) is a harmful air pollutant that depends on the complex mixture of natural and anthropogenic emissions into the atmosphere. Thus, in different regions and seasons, the way that PM is formed and grows can differ. In this study, we use a combined statistical analysis of the chemical composition and particle size distribution to determine what drives particle formation and growth across seasons, using varying wind directions to elucidate the role of different sources.
Kohei Sakata, Aya Sakaguchi, Yoshiaki Yamakawa, Chihiro Miyamoto, Minako Kurisu, and Yoshio Takahashi
Atmos. Chem. Phys., 23, 9815–9836, https://doi.org/10.5194/acp-23-9815-2023, https://doi.org/10.5194/acp-23-9815-2023, 2023
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Anthropogenic iron is the dominant source of dissolved Fe in aerosol particles, but its contribution to dissolved Fe in aerosol particles has not been quantitatively evaluated. We established the molar concentration ratio of dissolved Fe to dissolved Al as a new indicator to evaluate the contribution of anthropogenic iron. As a result, about 10 % of dissolved Fe in aerosol particles was derived from anthropogenic iron when aerosol particles were transported from East Asia to the Pacific Ocean.
Li Li, Qiyuan Wang, Jie Tian, Huikun Liu, Yong Zhang, Steven Sai Hang Ho, Weikang Ran, and Junji Cao
Atmos. Chem. Phys., 23, 9597–9612, https://doi.org/10.5194/acp-23-9597-2023, https://doi.org/10.5194/acp-23-9597-2023, 2023
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The Tibetan Plateau has a unique geographical location, but there is a lack of detailed research on the real-time characteristics of full aerosol composition. This study elaborates the changes in chemical characteristics between transport and local fine particles during the pre-monsoon, reveals the size distribution and the mixing states of different individual particles, and highlights the contributions of photooxidation and aqueous reaction to the formation of the secondary species.
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Short summary
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.
We present the first piece of observational evidence of the increasing trend of fine nitrate...
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