Articles | Volume 14, issue 12
https://doi.org/10.5194/acp-14-6089-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-14-6089-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
20 Jun 2014
Research article |
| 20 Jun 2014
Variations of ground-level O3 and its precursors in Beijing in summertime between 2005 and 2011
Q. Zhang
State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
M. Shao
State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
X. Wang
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
S. Lu
State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
K. Lu
State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
M. Wang
State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
L. Chen
State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing, China
C.-C. Chang
Research Center for Environmental Change, Academia Sinica, Taipei 115, Taiwan
S. C. Liu
Research Center for Environmental Change, Academia Sinica, Taipei 115, Taiwan
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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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Mingfu Cai, Chenshuo Ye, Bin Yuan, Shan Huang, E Zheng, Suxia Yang, Zelong Wang, Yi Lin, Tiange Li, Weiwei Hu, Wei Chen, Qicong Song, Wei Li, Yuwen Peng, Baoling Liang, Qibin Sun, Jun Zhao, Duohong Chen, Jiaren Sun, Zhiyong Yang, and Min Shao
Atmos. Chem. Phys., 24, 13065–13079, https://doi.org/10.5194/acp-24-13065-2024, https://doi.org/10.5194/acp-24-13065-2024, 2024
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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.
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Atmos. Meas. Tech., 17, 4065–4079, https://doi.org/10.5194/amt-17-4065-2024, https://doi.org/10.5194/amt-17-4065-2024, 2024
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Atmos. Chem. Phys., 24, 4017–4027, https://doi.org/10.5194/acp-24-4017-2024, https://doi.org/10.5194/acp-24-4017-2024, 2024
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Yixin Hao, Jun Zhou, Jie-Ping Zhou, Yan Wang, Suxia Yang, Yibo Huangfu, Xiao-Bing Li, Chunsheng Zhang, Aiming Liu, Yanfeng Wu, Yaqing Zhou, Shuchun Yang, Yuwen Peng, Jipeng Qi, Xianjun He, Xin Song, Yubin Chen, Bin Yuan, and Min Shao
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By employing an improved net photochemical ozone production rate (NPOPR) detection system based on the dual-channel reaction chamber technique, we measured the net photochemical ozone production rate in the Pearl River Delta in China. The photochemical ozone formation mechanisms in the reaction and reference chambers were investigated using the observation-data-constrained box model, which helped us to validate the NPOPR detection system and understand photochemical ozone formation mechanism.
Yiyu Cai, Chenshuo Ye, Wei Chen, Weiwei Hu, Wei Song, Yuwen Peng, Shan Huang, Jipeng Qi, Sihang Wang, Chaomin Wang, Caihong Wu, Zelong Wang, Baolin Wang, Xiaofeng Huang, Lingyan He, Sasho Gligorovski, Bin Yuan, Min Shao, and Xinming Wang
Atmos. Chem. Phys., 23, 8855–8877, https://doi.org/10.5194/acp-23-8855-2023, https://doi.org/10.5194/acp-23-8855-2023, 2023
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We studied the variability and molecular composition of ambient oxidized organic nitrogen (OON) in both gas and particle phases using a state-of-the-art online mass spectrometer in urban air. Biomass burning and secondary formation were found to be the two major sources of OON. Daytime nitrate radical chemistry for OON formation was more important than previously thought. Our results improved the understanding of the sources and molecular composition of OON in the polluted urban atmosphere.
Kevin J. Nihill, Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Bin Yuan, Jordan E. Krechmer, Kanako Sekimoto, Jose L. Jimenez, Joost de Gouw, Christopher D. Cappa, Colette L. Heald, Carsten Warneke, and Jesse H. Kroll
Atmos. Chem. Phys., 23, 7887–7899, https://doi.org/10.5194/acp-23-7887-2023, https://doi.org/10.5194/acp-23-7887-2023, 2023
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In this work, we collect emissions from controlled burns of biomass fuels that can be found in the western United States into an environmental chamber in order to simulate their oxidation as they pass through the atmosphere. These findings provide a detailed characterization of the composition of the atmosphere downwind of wildfires. In turn, this will help to explore the effects of these changing emissions on downwind populations and will also directly inform atmospheric and climate models.
Yaqin Gao, Hongli Wang, Lingling Yuan, Shengao Jing, Bin Yuan, Guofeng Shen, Liang Zhu, Abigail Koss, Yingjie Li, Qian Wang, Dan Dan Huang, Shuhui Zhu, Shikang Tao, Shengrong Lou, and Cheng Huang
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A near-complete speciation of reactive organic gases from residential combustion was developed to get more insights into their atmospheric effects. Oxygenated species, higher hydrocarbons and nitrogen-containing species played larger roles in these emissions compared with common hydrocarbons. Based on the near-complete speciation, these emissions were largely underestimated, leading to more underestimation of their hydroxyl radical reactivity and secondary organic aerosol formation potential.
Juan Hong, Min Tang, Qiaoqiao Wang, Nan Ma, Shaowen Zhu, Shaobin Zhang, Xihao Pan, Linhong Xie, Guo Li, Uwe Kuhn, Chao Yan, Jiangchuan Tao, Ye Kuang, Yao He, Wanyun Xu, Runlong Cai, Yaqing Zhou, Zhibin Wang, Guangsheng Zhou, Bin Yuan, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 23, 5699–5713, https://doi.org/10.5194/acp-23-5699-2023, https://doi.org/10.5194/acp-23-5699-2023, 2023
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A comprehensive investigation of the characteristics of new particle formation (NPF) events was conducted at a rural site on the North China Plain (NCP), China, during the wintertime of 2018 by covering the particle number size distribution down to sub–3 nm. Potential mechanisms for NPF under the current environment were explored, followed by a further discussion on the factors governing the occurrence of NPF at this rural site compared with other regions (e.g., urban areas) in the NCP region.
Tingting Feng, Yingkun Wang, Weiwei Hu, Ming Zhu, Wei Song, Wei Chen, Yanyan Sang, Zheng Fang, Wei Deng, Hua Fang, Xu Yu, Cheng Wu, Bin Yuan, Shan Huang, Min Shao, Xiaofeng Huang, Lingyan He, Young Ro Lee, Lewis Gregory Huey, Francesco Canonaco, Andre S. H. Prevot, and Xinming Wang
Atmos. Chem. Phys., 23, 611–636, https://doi.org/10.5194/acp-23-611-2023, https://doi.org/10.5194/acp-23-611-2023, 2023
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To investigate the impact of aging processes on organic aerosols (OA), we conducted a comprehensive field study at a continental remote site using an on-line mass spectrometer. The results show that OA in the Chinese outflows were strongly influenced by upwind anthropogenic emissions. The aging processes can significantly decrease the OA volatility and result in a varied viscosity of OA under different circumstances, signifying the complex physiochemical properties of OA in aged plumes.
Yubin Chen, Bin Yuan, Chaomin Wang, Sihang Wang, Xianjun He, Caihong Wu, Xin Song, Yibo Huangfu, Xiao-Bing Li, Yijia Liao, and Min Shao
Atmos. Meas. Tech., 15, 6935–6947, https://doi.org/10.5194/amt-15-6935-2022, https://doi.org/10.5194/amt-15-6935-2022, 2022
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In this study, we demonstrate that selective online measurements of cycloalkanes can be achieved using proton transfer reaction time-of-flight mass spectrometry with NO+ chemical ionization (NO+ PTR-ToF-MS), with fast response and low detection limits. Applications of this method in both urban air and emission sources will be shown.
Haichao Wang, Bin Yuan, E Zheng, Xiaoxiao Zhang, Jie Wang, Keding Lu, Chenshuo Ye, Lei Yang, Shan Huang, Weiwei Hu, Suxia Yang, Yuwen Peng, Jipeng Qi, Sihang Wang, Xianjun He, Yubin Chen, Tiange Li, Wenjie Wang, Yibo Huangfu, Xiaobing Li, Mingfu Cai, Xuemei Wang, and Min Shao
Atmos. Chem. Phys., 22, 14837–14858, https://doi.org/10.5194/acp-22-14837-2022, https://doi.org/10.5194/acp-22-14837-2022, 2022
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We present intensive field measurement of ClNO2 in the Pearl River Delta in 2019. Large variation in the level, formation, and atmospheric impacts of ClNO2 was found in different air masses. ClNO2 formation was limited by the particulate chloride (Cl−) and aerosol surface area. Our results reveal that Cl− originated from various anthropogenic emissions rather than sea sources and show minor contribution to the O3 pollution and photochemistry.
Biao Luo, Ye Kuang, Shan Huang, Qicong Song, Weiwei Hu, Wei Li, Yuwen Peng, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 22, 12401–12415, https://doi.org/10.5194/acp-22-12401-2022, https://doi.org/10.5194/acp-22-12401-2022, 2022
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We performed comprehensive analysis on biomass burning organic aerosol (BBOA) size distributions, as well as mass scattering and absorption efficiencies, with an improved method of on-line quantification of brown carbon absorptions. Both BBOA volume size distribution and retrieved refractive index depend highly on combustion conditions represented by the black carbon content, which has significant implications for BBOA climate effect simulations.
Xiao-Bing Li, Bin Yuan, Sihang Wang, Chunlin Wang, Jing Lan, Zhijie Liu, Yongxin Song, Xianjun He, Yibo Huangfu, Chenglei Pei, Peng Cheng, Suxia Yang, Jipeng Qi, Caihong Wu, Shan Huang, Yingchang You, Ming Chang, Huadan Zheng, Wenda Yang, Xuemei Wang, and Min Shao
Atmos. Chem. Phys., 22, 10567–10587, https://doi.org/10.5194/acp-22-10567-2022, https://doi.org/10.5194/acp-22-10567-2022, 2022
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High-time-resolution measurements of volatile organic compounds (VOCs) were made using an online mass spectrometer at a 600 m tall tower in urban region. Compositions, temporal variations, and sources of VOCs were quantitatively investigated in this study. We find that VOC measurements in urban regions aloft could better characterize source characteristics of anthropogenic emissions. Our results could provide important implications in making future strategies for control of VOCs.
Sihang Wang, Bin Yuan, Caihong Wu, Chaomin Wang, Tiange Li, Xianjun He, Yibo Huangfu, Jipeng Qi, Xiao-Bing Li, Qing'e Sha, Manni Zhu, Shengrong Lou, Hongli Wang, Thomas Karl, Martin Graus, Zibing Yuan, and Min Shao
Atmos. Chem. Phys., 22, 9703–9720, https://doi.org/10.5194/acp-22-9703-2022, https://doi.org/10.5194/acp-22-9703-2022, 2022
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Volatile organic compound (VOC) emissions from vehicles are measured using online mass spectrometers. Differences between gasoline and diesel vehicles are observed with higher emission factors of most oxygenated VOCs (OVOCs) and heavier aromatics from diesel vehicles. A higher aromatics / toluene ratio could provide good indicators to distinguish emissions from both vehicle types. We show that OVOCs account for significant contributions to VOC emissions from vehicles, especially diesel vehicles.
Yihang Yu, Peng Cheng, Huirong Li, Wenda Yang, Baobin Han, Wei Song, Weiwei Hu, Xinming Wang, Bin Yuan, Min Shao, Zhijiong Huang, Zhen Li, Junyu Zheng, Haichao Wang, and Xiaofang Yu
Atmos. Chem. Phys., 22, 8951–8971, https://doi.org/10.5194/acp-22-8951-2022, https://doi.org/10.5194/acp-22-8951-2022, 2022
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We have investigated the budget of HONO at an urban site in Guangzhou. Budget and comprehensive uncertainty analysis suggest that at such locations as ours, HONO direct emissions and NO + OH can become comparable or even surpass other HONO sources that typically receive greater attention and interest, such as the NO2 heterogeneous source and the unknown daytime photolytic source. Our findings emphasize the need to reduce the uncertainties of both conventional and novel HONO sources and sinks.
Qi Zhang, Shiguo Jia, Weihua Chen, Jingying Mao, Liming Yang, Padmaja Krishnan, Sayantan Sarkar, Min Shao, and Xuemei Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-394, https://doi.org/10.5194/acp-2022-394, 2022
Revised manuscript not accepted
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We use satellite data in the establishment of methylamines marine biological emission (MBE) inventory for the first time, which considers effects of actual marine environment on methylamines emission fluxes. MBE fluxes of monomethylamine and trimethylamines can be comparable with or even higher than that of terrestrial anthropogenic emissions , while for dimethylamines, the ocean acts as a sink. Wind and Chlorophyll-a were potentially the most important factors affecting MBE fluxes.
Mingfu Cai, Shan Huang, Baoling Liang, Qibin Sun, Li Liu, Bin Yuan, Min Shao, Weiwei Hu, Wei Chen, Qicong Song, Wei Li, Yuwen Peng, Zelong Wang, Duohong Chen, Haobo Tan, Hanbin Xu, Fei Li, Xuejiao Deng, Tao Deng, Jiaren Sun, and Jun Zhao
Atmos. Chem. Phys., 22, 8117–8136, https://doi.org/10.5194/acp-22-8117-2022, https://doi.org/10.5194/acp-22-8117-2022, 2022
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This study investigated the size dependence and diurnal variation in organic aerosol hygroscopicity, volatility, and cloud condensation nuclei (CCN) activity. We found that the physical properties of OA could vary in a large range at different particle sizes and affected the number concentration of CCN (NCCN) at all supersaturations. Our results highlight the importance of evaluating the atmospheric evolution processes of OA at different size ranges and their impact on climate effects.
Li Liu, Ye Kuang, Miaomiao Zhai, Biao Xue, Yao He, Jun Tao, Biao Luo, Wanyun Xu, Jiangchuan Tao, Changqin Yin, Fei Li, Hanbing Xu, Tao Deng, Xuejiao Deng, Haobo Tan, and Min Shao
Atmos. Chem. Phys., 22, 7713–7726, https://doi.org/10.5194/acp-22-7713-2022, https://doi.org/10.5194/acp-22-7713-2022, 2022
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Using simultaneous measurements of a humidified nephelometer system and an aerosol chemical speciation monitor in winter in Guangzhou, the strongest scattering ability of more oxidized oxygenated organic aerosol (MOOA) among aerosol components considering their dry-state scattering ability and water uptake ability was revealed, leading to large impacts of MOOA on visibility degradation. This has important implications for visibility improvement in China and aerosol radiative effect simulation.
Suxia Yang, Bin Yuan, Yuwen Peng, Shan Huang, Wei Chen, Weiwei Hu, Chenglei Pei, Jun Zhou, David D. Parrish, Wenjie Wang, Xianjun He, Chunlei Cheng, Xiao-Bing Li, Xiaoyun Yang, Yu Song, Haichao Wang, Jipeng Qi, Baolin Wang, Chen Wang, Chaomin Wang, Zelong Wang, Tiange Li, E Zheng, Sihang Wang, Caihong Wu, Mingfu Cai, Chenshuo Ye, Wei Song, Peng Cheng, Duohong Chen, Xinming Wang, Zhanyi Zhang, Xuemei Wang, Junyu Zheng, and Min Shao
Atmos. Chem. Phys., 22, 4539–4556, https://doi.org/10.5194/acp-22-4539-2022, https://doi.org/10.5194/acp-22-4539-2022, 2022
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We use a model constrained using observations to study the formation of nitrate aerosol in and downwind of a representative megacity. We found different contributions of various chemical reactions to ground-level nitrate concentrations between urban and suburban regions. We also show that controlling VOC emissions are effective for decreasing nitrate formation in both urban and regional environments, although VOCs are not direct precursors of nitrate aerosol.
Wenjie Wang, Bin Yuan, Yuwen Peng, Hang Su, Yafang Cheng, Suxia Yang, Caihong Wu, Jipeng Qi, Fengxia Bao, Yibo Huangfu, Chaomin Wang, Chenshuo Ye, Zelong Wang, Baolin Wang, Xinming Wang, Wei Song, Weiwei Hu, Peng Cheng, Manni Zhu, Junyu Zheng, and Min Shao
Atmos. Chem. Phys., 22, 4117–4128, https://doi.org/10.5194/acp-22-4117-2022, https://doi.org/10.5194/acp-22-4117-2022, 2022
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From thorough measurements of numerous oxygenated volatile organic compounds, we show that their photodissociation can be important for radical production and ozone formation in the atmosphere. This effect was underestimated in previous studies, as measurements of them were lacking.
Xiajie Yang, Qiaoqiao Wang, Nan Ma, Weiwei Hu, Yang Gao, Zhijiong Huang, Junyu Zheng, Bin Yuan, Ning Yang, Jiangchuan Tao, Juan Hong, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3743–3762, https://doi.org/10.5194/acp-22-3743-2022, https://doi.org/10.5194/acp-22-3743-2022, 2022
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We use the GEOS-Chem model with additional anthropogenic and biomass burning chlorine emissions combined with updated parameterizations for N2O5 ＋ Cl chemistry to investigate the impacts of chlorine chemistry on air quality in China. Our study not only significantly improves the model's performance but also demonstrates the importance of non-sea-salt chlorine sources as well as an appropriate parameterization for N2O5 ＋ Cl chemistry to the impact of chlorine chemistry in China.
Ziwei Mo, Ru Cui, Bin Yuan, Huihua Cai, Brian C. McDonald, Meng Li, Junyu Zheng, and Min Shao
Atmos. Chem. Phys., 21, 13655–13666, https://doi.org/10.5194/acp-21-13655-2021, https://doi.org/10.5194/acp-21-13655-2021, 2021
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There is a lack of detailed understanding of NMVOC emissions from the use of volatile chemical products (VCPs) in China. This study used a mass balance method to compile a long-term emission inventory for solvent use (including coatings, adhesives, inks, pesticides, cleaners and personal care products) in China during 2000–2017. The striking growth and recent trend of solvent use NMVOC emissions can give important implications for air quality modeling and NMVOC control strategies in China.
Luolin Wu, Jian Hang, Xuemei Wang, Min Shao, and Cheng Gong
Geosci. Model Dev., 14, 4655–4681, https://doi.org/10.5194/gmd-14-4655-2021, https://doi.org/10.5194/gmd-14-4655-2021, 2021
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In order to investigate street-scale flow and air quality, this study has developed APFoam 1.0 to examine the reactive pollutant formation and dispersion in the urban area. The model has been validated and shows good agreement with wind tunnel experimental data. Model sensitivity cases reveal that vehicle emissions, background concentrations, and wind conditions are the key factors affecting the photochemical reaction process.
Benjamin A. Nault, Duseong S. Jo, Brian C. McDonald, Pedro Campuzano-Jost, Douglas A. Day, Weiwei Hu, Jason C. Schroder, James Allan, Donald R. Blake, Manjula R. Canagaratna, Hugh Coe, Matthew M. Coggon, Peter F. DeCarlo, Glenn S. Diskin, Rachel Dunmore, Frank Flocke, Alan Fried, Jessica B. Gilman, Georgios Gkatzelis, Jacqui F. Hamilton, Thomas F. Hanisco, Patrick L. Hayes, Daven K. Henze, Alma Hodzic, James Hopkins, Min Hu, L. Greggory Huey, B. Thomas Jobson, William C. Kuster, Alastair Lewis, Meng Li, Jin Liao, M. Omar Nawaz, Ilana B. Pollack, Jeffrey Peischl, Bernhard Rappenglück, Claire E. Reeves, Dirk Richter, James M. Roberts, Thomas B. Ryerson, Min Shao, Jacob M. Sommers, James Walega, Carsten Warneke, Petter Weibring, Glenn M. Wolfe, Dominique E. Young, Bin Yuan, Qiang Zhang, Joost A. de Gouw, and Jose L. Jimenez
Atmos. Chem. Phys., 21, 11201–11224, https://doi.org/10.5194/acp-21-11201-2021, https://doi.org/10.5194/acp-21-11201-2021, 2021
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Secondary organic aerosol (SOA) is an important aspect of poor air quality for urban regions around the world, where a large fraction of the population lives. However, there is still large uncertainty in predicting SOA in urban regions. Here, we used data from 11 urban campaigns and show that the variability in SOA production in these regions is predictable and is explained by key emissions. These results are used to estimate the premature mortality associated with SOA in urban regions.
Ye Kuang, Shan Huang, Biao Xue, Biao Luo, Qicong Song, Wei Chen, Weiwei Hu, Wei Li, Pusheng Zhao, Mingfu Cai, Yuwen Peng, Jipeng Qi, Tiange Li, Sihang Wang, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 21, 10375–10391, https://doi.org/10.5194/acp-21-10375-2021, https://doi.org/10.5194/acp-21-10375-2021, 2021
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We found that organic aerosol factors with identified sources perform much better than oxidation level parameters in characterizing variations in organic aerosol hygroscopicity, and secondary aerosol formations associated with different sources have distinct effects on organic aerosol hygroscopicity. It reveals that source-oriented organic aerosol hygroscopicity investigations might result in more appropriate parameterization approaches in chemical and climate models.
Mingfu Cai, Baoling Liang, Qibin Sun, Li Liu, Bin Yuan, Min Shao, Shan Huang, Yuwen Peng, Zelong Wang, Haobo Tan, Fei Li, Hanbin Xu, Duohong Chen, and Jun Zhao
Atmos. Chem. Phys., 21, 8575–8592, https://doi.org/10.5194/acp-21-8575-2021, https://doi.org/10.5194/acp-21-8575-2021, 2021
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This study investigated the contribution of new particle formation (NPF) events to the number concentration of cloud condensation nuclei (NCCN) and its controlling factors in the Pearl River Delta region. The results show that the surfactant effect can decrease the critical diameter and significantly increase the NCCN during the NPF event. In addition, the growth rate is founded to be the most important controlling factor that affects NCCN for growth of newly-formed particles to the CCN sizes.
Chenshuo Ye, Bin Yuan, Yi Lin, Zelong Wang, Weiwei Hu, Tiange Li, Wei Chen, Caihong Wu, Chaomin Wang, Shan Huang, Jipeng Qi, Baolin Wang, Chen Wang, Wei Song, Xinming Wang, E Zheng, Jordan E. Krechmer, Penglin Ye, Zhanyi Zhang, Xuemei Wang, Douglas R. Worsnop, and Min Shao
Atmos. Chem. Phys., 21, 8455–8478, https://doi.org/10.5194/acp-21-8455-2021, https://doi.org/10.5194/acp-21-8455-2021, 2021
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We performed measurements of gaseous and particulate organic compounds using a state-of-the-art online mass spectrometer in urban air. Using the dataset, we provide a holistic chemical characterization of oxygenated organic compounds in the polluted urban atmosphere, which can serve as a reference for the future field measurements of organic compounds in cities.
Wenjie Wang, Jipeng Qi, Jun Zhou, Bin Yuan, Yuwen Peng, Sihang Wang, Suxia Yang, Jonathan Williams, Vinayak Sinha, and Min Shao
Atmos. Meas. Tech., 14, 2285–2298, https://doi.org/10.5194/amt-14-2285-2021, https://doi.org/10.5194/amt-14-2285-2021, 2021
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We designed a new reactor for measurements of OH reactivity (i.e., OH radical loss frequency) based on the comparative reactivity method under
high-NOx conditions, such as in cities. We performed a series of laboratory tests to evaluate the new reactor. The new reactor was used in the field and performed well in measuring OH reactivity in air influenced by upwind cities.
Wenjie Wang, David D. Parrish, Xin Li, Min Shao, Ying Liu, Ziwei Mo, Sihua Lu, Min Hu, Xin Fang, Yusheng Wu, Limin Zeng, and Yuanhang Zhang
Atmos. Chem. Phys., 20, 15617–15633, https://doi.org/10.5194/acp-20-15617-2020, https://doi.org/10.5194/acp-20-15617-2020, 2020
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During the past decade, China has devoted very substantial resources to improving the environment. These efforts have improved atmospheric particulate matter loading, but ambient ozone levels have continued to increase. In this paper we investigate the causes of the increasing ozone concentrations through analysis of a data set that is, to our knowledge, unique: a 12-year data set including ground-level O3, NOx, and VOC precursors collected at an urban site in Beijing.
Caihong Wu, Chaomin Wang, Sihang Wang, Wenjie Wang, Bin Yuan, Jipeng Qi, Baolin Wang, Hongli Wang, Chen Wang, Wei Song, Xinming Wang, Weiwei Hu, Shengrong Lou, Chenshuo Ye, Yuwen Peng, Zelong Wang, Yibo Huangfu, Yan Xie, Manni Zhu, Junyu Zheng, Xuemei Wang, Bin Jiang, Zhanyi Zhang, and Min Shao
Atmos. Chem. Phys., 20, 14769–14785, https://doi.org/10.5194/acp-20-14769-2020, https://doi.org/10.5194/acp-20-14769-2020, 2020
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Based on measurements from an online mass spectrometer, we quantify volatile organic compound (VOC) concentrations from numerous ions of the mass spectrometer, using information from laboratory-obtained calibration results. We find that most VOC concentrations are from oxygenated VOCs (OVOCs). We further show that these OVOCs also contribute significantly to OH reactivity. Our results suggest the important role of OVOCs in VOC emissions and chemistry in urban air.
Sarah E. Benish, Hao He, Xinrong Ren, Sandra J. Roberts, Ross J. Salawitch, Zhanqing Li, Fei Wang, Yuying Wang, Fang Zhang, Min Shao, Sihua Lu, and Russell R. Dickerson
Atmos. Chem. Phys., 20, 14523–14545, https://doi.org/10.5194/acp-20-14523-2020, https://doi.org/10.5194/acp-20-14523-2020, 2020
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Airborne observations of ozone and related pollutants show smog was pervasive in spring 2016 over Hebei Province, China. We find high amounts of ozone precursors throughout and even above the PBL, continuing to generate ozone at high rates to be potentially transported downwind. Concentrations even in the rural areas of this highly industrialized province promote widespread ozone production, and we show that to improve air quality over Hebei both NOx and VOCs should be targeted.
Chaomin Wang, Bin Yuan, Caihong Wu, Sihang Wang, Jipeng Qi, Baolin Wang, Zelong Wang, Weiwei Hu, Wei Chen, Chenshuo Ye, Wenjie Wang, Yele Sun, Chen Wang, Shan Huang, Wei Song, Xinming Wang, Suxia Yang, Shenyang Zhang, Wanyun Xu, Nan Ma, Zhanyi Zhang, Bin Jiang, Hang Su, Yafang Cheng, Xuemei Wang, and Min Shao
Atmos. Chem. Phys., 20, 14123–14138, https://doi.org/10.5194/acp-20-14123-2020, https://doi.org/10.5194/acp-20-14123-2020, 2020
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We utilized a novel online mass spectrometry method to measure the total concentration of higher alkanes at each carbon number at two different sites in China, allowing us to take into account SOA contributions from all isomers for higher alkanes. We found that higher alkanes account for significant fractions of SOA formation at the two sites. The contributions are comparable to or even higher than single-ring aromatics, the most-recognized SOA precursors in urban air.
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.
Mingfu Cai, Baoling Liang, Qibin Sun, Shengzhen Zhou, Xiaoyang Chen, Bin Yuan, Min Shao, Haobo Tan, and Jun Zhao
Atmos. Chem. Phys., 20, 9153–9167, https://doi.org/10.5194/acp-20-9153-2020, https://doi.org/10.5194/acp-20-9153-2020, 2020
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Cloud condensation nuclei activity in marine atmosphere affects cloud formation and the solar radiation balance over ocean. We employed advanced instruments to measure aerosol hygroscopicity and chemical composition in the northern South China Sea. Our results show that marine aerosols can be affected by local emissions or pollutants from long-range transport. Our study highlights dynamical variations in particle properties and the impact of long-range transport on this region during summertime.
James M. Roberts, Chelsea E. Stockwell, Robert J. Yokelson, Joost de Gouw, Yong Liu, Vanessa Selimovic, Abigail R. Koss, Kanako Sekimoto, Matthew M. Coggon, Bin Yuan, Kyle J. Zarzana, Steven S. Brown, Cristina Santin, Stefan H. Doerr, and Carsten Warneke
Atmos. Chem. Phys., 20, 8807–8826, https://doi.org/10.5194/acp-20-8807-2020, https://doi.org/10.5194/acp-20-8807-2020, 2020
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We measured total reactive nitrogen, Nr, in lab fires from western North American fuels, along with measurements of individual nitrogen compounds. We measured the amount of N that gets converted to inactive compounds (avg. 70 %), and the amount that is accounted for by individual species (85 % of remaining N). We provide guidelines for how the reactive nitrogen is distributed among individual compounds such as NOx and ammonia. This will help estimates and predictions of wildfire emissions.
Luolin Wu, Ming Chang, Xuemei Wang, Jian Hang, Jinpu Zhang, Liqing Wu, and Min Shao
Geosci. Model Dev., 13, 23–40, https://doi.org/10.5194/gmd-13-23-2020, https://doi.org/10.5194/gmd-13-23-2020, 2020
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We developed the Real-time On-road Emission (ROE v1.0) model to obtain the street-scale on-road hot emissions by using real-time big data for traffic provided by the Gaode Map navigation application. The results are close to other emission inventories. Meanwhile, we applied our results to a street-level air quality model for studying the impact of the national holiday traffic volume change on air quality. The model can be further extended to more districts in China or other countries.
Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Kanako Sekimoto, Bin Yuan, Jessica B. Gilman, David H. Hagan, Vanessa Selimovic, Kyle J. Zarzana, Steven S. Brown, James M. Roberts, Markus Müller, Robert Yokelson, Armin Wisthaler, Jordan E. Krechmer, Jose L. Jimenez, Christopher Cappa, Jesse H. Kroll, Joost de Gouw, and Carsten Warneke
Atmos. Chem. Phys., 19, 14875–14899, https://doi.org/10.5194/acp-19-14875-2019, https://doi.org/10.5194/acp-19-14875-2019, 2019
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Wildfire emissions significantly contribute to adverse air quality; however, the chemical processes that lead to hazardous pollutants, such as ozone, are not fully understood. In this study, we describe laboratory experiments where we simulate the atmospheric chemistry of smoke emitted from a range of biomass fuels. We show that certain understudied compounds, such as furans and phenolic compounds, are significant contributors to pollutants formed as a result of typical atmospheric oxidation.
Yahui Bian, Zhijiong Huang, Jiamin Ou, Zhuangmin Zhong, Yuanqian Xu, Zhiwei Zhang, Xiao Xiao, Xiao Ye, Yuqi Wu, Xiaohong Yin, Cheng Li, Liangfu Chen, Min Shao, and Junyu Zheng
Atmos. Chem. Phys., 19, 11701–11719, https://doi.org/10.5194/acp-19-11701-2019, https://doi.org/10.5194/acp-19-11701-2019, 2019
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During 2006–2015, emissions of SO2, NOx, PM2.5 and PM10 saw an obvious downtrend. However, most emissions still have large reduction potential. On-road mobile sources and solvent use are the two key sources that should receive more effective control measures in GD. Also, controls measures on VOC and NH3 should be weighted since they still increased in 2006–2015. Since most control measures focused on PRD rather than non-PRD in GD, emissions in non-PRD were increasingly important.
Wenjie Wang, Xin Li, Min Shao, Min Hu, Limin Zeng, Yusheng Wu, and Tianyi Tan
Atmos. Chem. Phys., 19, 9413–9429, https://doi.org/10.5194/acp-19-9413-2019, https://doi.org/10.5194/acp-19-9413-2019, 2019
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We quantitatively evaluated the relationship between photolysis frequencies and AOD based on 4 years of observational data in Beijing. This study concludes that the influence of aerosol on photolysis frequencies and thus on the rate of oxidation of VOCs and NOx to ozone is important for determining the atmospheric effects of controlling the precursor emissions of these two important air pollutants (aerosols and ozone).
Xin Chen, Dylan B. Millet, Hanwant B. Singh, Armin Wisthaler, Eric C. Apel, Elliot L. Atlas, Donald R. Blake, Ilann Bourgeois, Steven S. Brown, John D. Crounse, Joost A. de Gouw, Frank M. Flocke, Alan Fried, Brian G. Heikes, Rebecca S. Hornbrook, Tomas Mikoviny, Kyung-Eun Min, Markus Müller, J. Andrew Neuman, Daniel W. O'Sullivan, Jeff Peischl, Gabriele G. Pfister, Dirk Richter, James M. Roberts, Thomas B. Ryerson, Stephen R. Shertz, Chelsea R. Thompson, Victoria Treadaway, Patrick R. Veres, James Walega, Carsten Warneke, Rebecca A. Washenfelder, Petter Weibring, and Bin Yuan
Atmos. Chem. Phys., 19, 9097–9123, https://doi.org/10.5194/acp-19-9097-2019, https://doi.org/10.5194/acp-19-9097-2019, 2019
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Volatile organic compounds (VOCs) affect air quality and modify the lifetimes of other pollutants. We combine a high-resolution 3-D atmospheric model with an ensemble of aircraft observations to perform an integrated analysis of the VOC budget over North America. We find that biogenic emissions provide the main source of VOC reactivity even in most major cities. Our findings point to key gaps in current models related to oxygenated VOCs and to the distribution of VOCs in the free troposphere.
Zhuoran He, Xuemei Wang, Zhenhao Ling, Jun Zhao, Hai Guo, Min Shao, and Zhe Wang
Atmos. Chem. Phys., 19, 8801–8816, https://doi.org/10.5194/acp-19-8801-2019, https://doi.org/10.5194/acp-19-8801-2019, 2019
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In this study, source apportionment of volatile organic compounds (VOCs) and their contributions to photochemical O3 formation were analyzed by the positive matrix factorization model and an observation-based model using data collected at a receptor site in the Pearl River Delta (PRD) region. Furthermore, the policies for controlling VOCs are briefly reviewed. The findings could provide quantitative information for devising appropriate measures against VOCs, NOx and O3 pollution in the PRD.
Liqing Wu, Xuemei Wang, Sihua Lu, Min Shao, and Zhenhao Ling
Atmos. Chem. Phys., 19, 8141–8161, https://doi.org/10.5194/acp-19-8141-2019, https://doi.org/10.5194/acp-19-8141-2019, 2019
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Semi-volatile and intermediate-volatility organic compounds (S–IVOCs) are considered critical precursors of secondary organic aerosol (SOA), which is an important component of fine particulate matter (PM2.5). In this study, an emission inventory of S–IVOCs in the Pearl River Delta (PRD) region was developed for the first time for the year 2010, while the contributions of S–IVOCs to SOA formation was evaluated by the WRF-Chem model.
Zhaofeng Tan, Keding Lu, Andreas Hofzumahaus, Hendrik Fuchs, Birger Bohn, Frank Holland, Yuhan Liu, Franz Rohrer, Min Shao, Kang Sun, Yusheng Wu, Limin Zeng, Yinsong Zhang, Qi Zou, Astrid Kiendler-Scharr, Andreas Wahner, and Yuanhang Zhang
Atmos. Chem. Phys., 19, 7129–7150, https://doi.org/10.5194/acp-19-7129-2019, https://doi.org/10.5194/acp-19-7129-2019, 2019
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Atmospheric OH, HO2, and RO2 radicals; OH reactivity; and trace gases measured in the Pearl River Delta in autumn 2014 are used for radical budget analyses. The RO2 budget suggests that unexplained OH reactivity is due to unmeasured volatile organic compounds. The OH budget points to a missing OH source and that of RO2 to a missing RO2 sink at low NO. This could indicate a common, unknown process that converts RO2 to OH without the involvement of NO, which would reduce ozone production by 30 %.
Guo Li, Yafang Cheng, Uwe Kuhn, Rongjuan Xu, Yudong Yang, Hannah Meusel, Zhibin Wang, Nan Ma, Yusheng Wu, Meng Li, Jonathan Williams, Thorsten Hoffmann, Markus Ammann, Ulrich Pöschl, Min Shao, and Hang Su
Atmos. Chem. Phys., 19, 2209–2232, https://doi.org/10.5194/acp-19-2209-2019, https://doi.org/10.5194/acp-19-2209-2019, 2019
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VOCs play a key role in atmospheric chemistry. Emission and deposition on soil have been suggested as important sources and sinks of atmospheric trace gases. The exchange characteristics and heterogeneous chemistry of VOCs on soil, however, are not well understood. We used a newly designed differential coated-wall flow tube system to investigate the long-term variability of bidirectional air–soil exchange of 13 VOCs at ambient air conditions of an urban background site in Beijing.
Kyle J. Zarzana, Vanessa Selimovic, Abigail R. Koss, Kanako Sekimoto, Matthew M. Coggon, Bin Yuan, William P. Dubé, Robert J. Yokelson, Carsten Warneke, Joost A. de Gouw, James M. Roberts, and Steven S. Brown
Atmos. Chem. Phys., 18, 15451–15470, https://doi.org/10.5194/acp-18-15451-2018, https://doi.org/10.5194/acp-18-15451-2018, 2018
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Emissions of glyoxal and methylglyoxal from fuels common to the western United States were measured using cavity-enhanced spectroscopy, which provides a more selective measurement of those compounds than was previously available. Primary emissions of glyoxal were lower than previously reported and showed variability between the different fuel groups. However, emissions of glyoxal relative to formaldehyde were constant across almost all the fuel groups at 6 %–7 %.
Daocheng Gong, Hao Wang, Shenyang Zhang, Yu Wang, Shaw Chen Liu, Hai Guo, Min Shao, Congrong He, Duohong Chen, Lingyan He, Lei Zhou, Lidia Morawska, Yuanhang Zhang, and Boguang Wang
Atmos. Chem. Phys., 18, 14417–14432, https://doi.org/10.5194/acp-18-14417-2018, https://doi.org/10.5194/acp-18-14417-2018, 2018
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The complex air pollution in the air-polluted Pearl River Delta (PRD) region in southern China has significantly elevated the background atmospheric oxidative capacity of the adjacent forests and subsequently lowered the levels of important biogenic volatile organic compounds, such as isoprene, which probably affect the regional air quality and ecological environment in the long term.
Weiqiang Yang, Yanli Zhang, Xinming Wang, Sheng Li, Ming Zhu, Qingqing Yu, Guanghui Li, Zhonghui Huang, Huina Zhang, Zhenfeng Wu, Wei Song, Jihua Tan, and Min Shao
Atmos. Chem. Phys., 18, 12663–12682, https://doi.org/10.5194/acp-18-12663-2018, https://doi.org/10.5194/acp-18-12663-2018, 2018
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We present observation-based evaluations of the reduction of ambient VOCs under intervention control measures during APEC China 2014 in Beijing and the contributions of emissions from domestic solid fuel burning to ambient VOCs during winter heating. Controlling vehicle exhaust and solvent use was found to be effective in reducing ambient VOCs in non-heating periods, and controlling emissions from residential burning of solid fuels became much more important during winter heating.
Zhaofeng Tan, Franz Rohrer, Keding Lu, Xuefei Ma, Birger Bohn, Sebastian Broch, Huabin Dong, Hendrik Fuchs, Georgios I. Gkatzelis, Andreas Hofzumahaus, Frank Holland, Xin Li, Ying Liu, Yuhan Liu, Anna Novelli, Min Shao, Haichao Wang, Yusheng Wu, Limin Zeng, Min Hu, Astrid Kiendler-Scharr, Andreas Wahner, and Yuanhang Zhang
Atmos. Chem. Phys., 18, 12391–12411, https://doi.org/10.5194/acp-18-12391-2018, https://doi.org/10.5194/acp-18-12391-2018, 2018
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We present the first wintertime OH, HO2, and RO2 measurements in Beijing, China. OH concentrations are nearly 2-fold larger than those observed in foreign cities during wintertime. The high OH and large OH reactivities indicate photochemical processes can be effective even during wintertime. A box model largely underestimated HO2 and RO2 concentrations during pollution episodes correlated with high NOx, indicating a deficit current chemistry in the high NOx regime.
Kanako Sekimoto, Abigail R. Koss, Jessica B. Gilman, Vanessa Selimovic, Matthew M. Coggon, Kyle J. Zarzana, Bin Yuan, Brian M. Lerner, Steven S. Brown, Carsten Warneke, Robert J. Yokelson, James M. Roberts, and Joost de Gouw
Atmos. Chem. Phys., 18, 9263–9281, https://doi.org/10.5194/acp-18-9263-2018, https://doi.org/10.5194/acp-18-9263-2018, 2018
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We found that on average 85 % of the VOC emissions from biomass burning across various fuels representative of the western US (including various coniferous and chaparral fuels) can be explained using only two emission profiles: (i) a high-temperature pyrolysis profile and (ii) a low-temperature pyrolysis profile. The high-temperature profile is quantitatively similar between different fuel types (r2 > 0.84), and likewise for the low-temperature profile.
Zhuofei Du, Min Hu, Jianfei Peng, Wenbin Zhang, Jing Zheng, Fangting Gu, Yanhong Qin, Yudong Yang, Mengren Li, Yusheng Wu, Min Shao, and Shijin Shuai
Atmos. Chem. Phys., 18, 9011–9023, https://doi.org/10.5194/acp-18-9011-2018, https://doi.org/10.5194/acp-18-9011-2018, 2018
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By combining approaches involving chassis dynamometer measurements and environmental chamber simulations, we find that gasoline direct injection (GDI) vehicles contribute more primary aerosol and secondary organic aerosol than port fuel injection (PFI) vehicles. Our results highlight the considerable potential contribution of GDI vehicles to urban air pollution, since the market share of GDI vehicles will dominate over that of PFI vehicles in the future.
Abigail R. Koss, Kanako Sekimoto, Jessica B. Gilman, Vanessa Selimovic, Matthew M. Coggon, Kyle J. Zarzana, Bin Yuan, Brian M. Lerner, Steven S. Brown, Jose L. Jimenez, Jordan Krechmer, James M. Roberts, Carsten Warneke, Robert J. Yokelson, and Joost de Gouw
Atmos. Chem. Phys., 18, 3299–3319, https://doi.org/10.5194/acp-18-3299-2018, https://doi.org/10.5194/acp-18-3299-2018, 2018
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Non-methane organic gases (NMOGs) were detected by proton-transfer-reaction mass spectrometry (PTR-ToF) during an extensive laboratory characterization of wildfire emissions. Identifications for PTR-ToF ion masses are proposed and supported by a combination of techniques. Overall excellent agreement with other instrumentation is shown. Scalable emission factors and ratios are reported for many newly reported reactive species. An analysis of chemical characteristics is presented.
Guo Li, Hang Su, Uwe Kuhn, Hannah Meusel, Markus Ammann, Min Shao, Ulrich Pöschl, and Yafang Cheng
Atmos. Chem. Phys., 18, 2669–2686, https://doi.org/10.5194/acp-18-2669-2018, https://doi.org/10.5194/acp-18-2669-2018, 2018
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Coated-wall flow tube reactors are frequently used to investigate gas uptake and heterogeneous or multiphase reaction kinetics under laminar flow conditions. In previous applications, the effects of coating surface roughness on flow conditions were not well quantified. In this study, a criterion is proposed to eliminate/minimize the potential effects of coating surface roughness on laminar flow in coated-wall flow tube experiments and validate the applications of diffusion correction methods.
Jianfei Peng, Min Hu, Song Guo, Zhuofei Du, Dongjie Shang, Jing Zheng, Jun Zheng, Limin Zeng, Min Shao, Yusheng Wu, Don Collins, and Renyi Zhang
Atmos. Chem. Phys., 17, 10333–10348, https://doi.org/10.5194/acp-17-10333-2017, https://doi.org/10.5194/acp-17-10333-2017, 2017
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Rapid growth of BC particles was observed in Beijing using a new outdoor chamber, with an average growth rate of 26 ± 11 nm h−1. Secondary organic aerosol (SOA) accounted for more than 90 % of the coating mass. The hygroscopic growth factor of BC particles increased to 1.06–1.08 upon ageing. The κ (kappa) values for BC particles were calculated as only 0.035, indicating that initial photochemical ageing of BC particles does not appreciably alter the particle hygroscopicity in Beijing.
Abigail Koss, Bin Yuan, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Patrick R. Veres, Jeff Peischl, Scott Eilerman, Rob Wild, Steven S. Brown, Chelsea R. Thompson, Thomas Ryerson, Thomas Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Mitchell Thayer, Frank N. Keutsch, Shane Murphy, and Joost de Gouw
Atmos. Meas. Tech., 10, 2941–2968, https://doi.org/10.5194/amt-10-2941-2017, https://doi.org/10.5194/amt-10-2941-2017, 2017
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Oil and gas extraction activity can cause air quality issues through emission of reactive chemicals. VOCs related to extraction operations in the United States were measured by PTR-ToF-MS from aircraft during the SONGNEX campaign in March–April 2015. The detailed analysis in this work provides a guide to interpreting PTR-ToF measurements in oil- and gas-producing regions, and it includes fundamental observations of VOC speciation and mixing ratios.
Yudong Yang, Min Shao, Stephan Keßel, Yue Li, Keding Lu, Sihua Lu, Jonathan Williams, Yuanhang Zhang, Liming Zeng, Anke C. Nölscher, Yusheng Wu, Xuemei Wang, and Junyu Zheng
Atmos. Chem. Phys., 17, 7127–7142, https://doi.org/10.5194/acp-17-7127-2017, https://doi.org/10.5194/acp-17-7127-2017, 2017
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Total OH reactivity is an important parameter to evaluate understanding of atmospheric chemistry, especially the VOC contribution to air pollution. Measured by comparative reactivity methods, total OH reactivity in Beijing and Heshan revealed significant differences between measured and calculated results, such as missing reactivity, which were related to unmeasured primary or secondary species. This missing reactivity would introduce a 21–30 % underestimation for ozone production efficiency.
Bin Yuan, Matthew M. Coggon, Abigail R. Koss, Carsten Warneke, Scott Eilerman, Jeff Peischl, Kenneth C. Aikin, Thomas B. Ryerson, and Joost A. de Gouw
Atmos. Chem. Phys., 17, 4945–4956, https://doi.org/10.5194/acp-17-4945-2017, https://doi.org/10.5194/acp-17-4945-2017, 2017
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In this study, we measured emissions of volatile organic compounds (VOCs) from concentrated animal feeding operations (CAFOs) using both mobile laboratory and aircraft measurements. We will use this data set to investigate chemical compositions of VOC emissions and sources apportionment for these VOC emissions in different facilities.
Brian M. Lerner, Jessica B. Gilman, Kenneth C. Aikin, Elliot L. Atlas, Paul D. Goldan, Martin Graus, Roger Hendershot, Gabriel A. Isaacman-VanWertz, Abigail Koss, William C. Kuster, Richard A. Lueb, Richard J. McLaughlin, Jeff Peischl, Donna Sueper, Thomas B. Ryerson, Travis W. Tokarek, Carsten Warneke, Bin Yuan, and Joost A. de Gouw
Atmos. Meas. Tech., 10, 291–313, https://doi.org/10.5194/amt-10-291-2017, https://doi.org/10.5194/amt-10-291-2017, 2017
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Whole air sampling followed by analysis by gas chromatography is a common technique for characterization of trace volatile organic compounds in the atmosphere. We describe a new automated gas chromatograph–mass spectrograph which uses a Stirling cooler for sample preconcentration at −165 °C without the need for a cryogen such as liquid nitrogen. We also discuss potential sources of artifacts from our electropolished stainless steel sampling system and present results from two field campaigns.
Zhaofeng Tan, Hendrik Fuchs, Keding Lu, Andreas Hofzumahaus, Birger Bohn, Sebastian Broch, Huabin Dong, Sebastian Gomm, Rolf Häseler, Lingyan He, Frank Holland, Xin Li, Ying Liu, Sihua Lu, Franz Rohrer, Min Shao, Baolin Wang, Ming Wang, Yusheng Wu, Limin Zeng, Yinsong Zhang, Andreas Wahner, and Yuanhang Zhang
Atmos. Chem. Phys., 17, 663–690, https://doi.org/10.5194/acp-17-663-2017, https://doi.org/10.5194/acp-17-663-2017, 2017
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In this study, we performed accurate OH measurements as well as selective HO2 and RO2 measurements at a rural site in North China Plain with state-of-the-art instruments newly developed. We confirmed the previous discovery on the enhancement of the OH in low NOx with which little O3 production was associated, and we found a missing RO2 source in high NOx which promoted higher O3 production. Our results are of vital importance for ozone abatement strategies currently under discussion for China.
Hendrik Fuchs, Zhaofeng Tan, Keding Lu, Birger Bohn, Sebastian Broch, Steven S. Brown, Huabin Dong, Sebastian Gomm, Rolf Häseler, Lingyan He, Andreas Hofzumahaus, Frank Holland, Xin Li, Ying Liu, Sihua Lu, Kyung-Eun Min, Franz Rohrer, Min Shao, Baolin Wang, Ming Wang, Yusheng Wu, Limin Zeng, Yinson Zhang, Andreas Wahner, and Yuanhang Zhang
Atmos. Chem. Phys., 17, 645–661, https://doi.org/10.5194/acp-17-645-2017, https://doi.org/10.5194/acp-17-645-2017, 2017
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OH reactivity was measured during a 1-month long campaign at a rural site in the North China Plain in 2014. OH reactivity measurements are compared to calculations using OH reactant measurements. Good agreement is found indicating that all important OH reactants were measured. In addition, the chemical OH budget is analyzed. In contrast to previous campaigns in China in 2006, no significant imbalance between OH production and destruction is found.
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.
Maria Zatko, Joseph Erbland, Joel Savarino, Lei Geng, Lauren Easley, Andrew Schauer, Timothy Bates, Patricia K. Quinn, Bonnie Light, David Morison, Hans D. Osthoff, Seth Lyman, William Neff, Bin Yuan, and Becky Alexander
Atmos. Chem. Phys., 16, 13837–13851, https://doi.org/10.5194/acp-16-13837-2016, https://doi.org/10.5194/acp-16-13837-2016, 2016
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This manuscript presents chemical and optical observations collected in the air and snow during UBWOS2014 in eastern Utah. These observations are used to calculate fluxes of reactive nitrogen associated with snow nitrate photolysis. Snow-sourced reactive nitrogen fluxes are compared to reactive nitrogen emission inventories to find that snow-sourced reactive nitrogen is a minor contributor to the reactive nitrogen budget, and thus wintertime ground-level ozone formation, in the Uintah Basin.
Wei Hu, Min Hu, Wei-Wei Hu, Hongya Niu, Jing Zheng, Yusheng Wu, Wentai Chen, Chen Chen, Lingyu Li, Min Shao, Shaodong Xie, and Yuanhang Zhang
Atmos. Chem. Phys., 16, 13213–13230, https://doi.org/10.5194/acp-16-13213-2016, https://doi.org/10.5194/acp-16-13213-2016, 2016
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An Aerodyne high-resolution time-of-flight AMS was deployed at a suburban site in the Sichuan Basin, southwestern China, under high emission intensity, and unique geographical and adverse meteorological conditions. OA was the most abundant component (36 %) in PM1, characterized by a relatively high oxidation state. The contributions of BBOA and BC to PM1 were high in primary emission episodes, highlighting the critical influence of biomass burning.
Guo Li, Hang Su, Xin Li, Uwe Kuhn, Hannah Meusel, Thorsten Hoffmann, Markus Ammann, Ulrich Pöschl, Min Shao, and Yafang Cheng
Atmos. Chem. Phys., 16, 10299–10311, https://doi.org/10.5194/acp-16-10299-2016, https://doi.org/10.5194/acp-16-10299-2016, 2016
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Indoor and outdoor formaldehyde (HCHO) are both of considerable concern because of its health effects and its role in atmospheric chemistry. The heterogeneous reactions between gaseous HCHO with soils can pose important impact on both HCHO budget and soil ecosystem. Our results confirms that HCHO uptake by soil is a complex process involving both adsorption/desorption and chemical reactions. Soil and soil-derived airborne particles can either act as a source or a sink for HCHO.
Abigail R. Koss, Carsten Warneke, Bin Yuan, Matthew M. Coggon, Patrick R. Veres, and Joost A. de Gouw
Atmos. Meas. Tech., 9, 2909–2925, https://doi.org/10.5194/amt-9-2909-2016, https://doi.org/10.5194/amt-9-2909-2016, 2016
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Using laboratory and field experiments, we have explored how the technique of NO+ chemical ionization mass spectrometry can be used to measure volatile organic compounds (VOCs) in the troposphere. Results include the design and operation of the instrument, an evaluation of the technique’s utility for atmospheric measurement, and a guide for data interpretation. Use of this technique will improve our understanding of VOC chemistry.
Bin Yuan, Abigail Koss, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Harald Stark, and Joost A. de Gouw
Atmos. Meas. Tech., 9, 2735–2752, https://doi.org/10.5194/amt-9-2735-2016, https://doi.org/10.5194/amt-9-2735-2016, 2016
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We present the development of a hydronium (H3O+) time of flight chemical ionization mass spectrometer (H3O+ ToF-CIMS). We characterize the humidity dependence of the reagent ions and VOC signals in details. The low mass cutoff issue of RF-only quadrupole leads to unusual humidity dependence of reagent ions. The new H3O+ ToF-CIMS was successfully deployed on the NOAA WP-3D research aircraft for the SONGNEX campaign in 2015 and some initial results from the SONGNEX campaign are presented.
Luping Su, Edward G. Patton, Jordi Vilà-Guerau de Arellano, Alex B. Guenther, Lisa Kaser, Bin Yuan, Fulizi Xiong, Paul B. Shepson, Li Zhang, David O. Miller, William H. Brune, Karsten Baumann, Eric Edgerton, Andrew Weinheimer, Pawel K. Misztal, Jeong-Hoo Park, Allen H. Goldstein, Kate M. Skog, Frank N. Keutsch, and John E. Mak
Atmos. Chem. Phys., 16, 7725–7741, https://doi.org/10.5194/acp-16-7725-2016, https://doi.org/10.5194/acp-16-7725-2016, 2016
Xuekun Fang, Min Shao, Andreas Stohl, Qiang Zhang, Junyu Zheng, Hai Guo, Chen Wang, Ming Wang, Jiamin Ou, Rona L. Thompson, and Ronald G. Prinn
Atmos. Chem. Phys., 16, 3369–3382, https://doi.org/10.5194/acp-16-3369-2016, https://doi.org/10.5194/acp-16-3369-2016, 2016
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This is the first study reporting top-down estimates of benzene and toluene emissions in southern China using atmospheric measurement data from a rural site in the area, an atmospheric transport model and an inverse modeling method. This study shows in detail the temporal and spatial differences between the inversion estimate and four different bottom-up emission inventories (RCP, REAS, MEIC; Yin et al., 2015). We propose that more observations are urgently needed in future.
Bin Yuan, John Liggio, Jeremy Wentzell, Shao-Meng Li, Harald Stark, James M. Roberts, Jessica Gilman, Brian Lerner, Carsten Warneke, Rui Li, Amy Leithead, Hans D. Osthoff, Robert Wild, Steven S. Brown, and Joost A. de Gouw
Atmos. Chem. Phys., 16, 2139–2153, https://doi.org/10.5194/acp-16-2139-2016, https://doi.org/10.5194/acp-16-2139-2016, 2016
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We describe high-resolution measurements of nitrated phenols using a time-of-flight chemical ionization mass spectrometer (ToF-CIMS). Strong diurnal profiles were observed for nitrated phenols, with concentration maxima at night. Box model simulations were able to reproduce the measured nitrated phenols.
Yaning Kang, Mingxu Liu, Yu Song, Xin Huang, Huan Yao, Xuhui Cai, Hongsheng Zhang, Ling Kang, Xuejun Liu, Xiaoyuan Yan, Hong He, Qiang Zhang, Min Shao, and Tong Zhu
Atmos. Chem. Phys., 16, 2043–2058, https://doi.org/10.5194/acp-16-2043-2016, https://doi.org/10.5194/acp-16-2043-2016, 2016
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The multi-year (1980–2012) comprehensive ammonia emissions inventories were compiled for China on 1 km × 1 km grid.
Various realistic parameters (ambient temperature, wind speed, soil acidity, synthetic fertilizer types, etc.) were considered in these inventories to synthetically refine the emission factors of ammonia volatilization according to local agricultural practice.
This paper shows the interannual trend and spatial distribution of ammonia emissions in details over recent decades.
R. J. Wild, P. M. Edwards, T. S. Bates, R. C. Cohen, J. A. de Gouw, W. P. Dubé, J. B. Gilman, J. Holloway, J. Kercher, A. R. Koss, L. Lee, B. M. Lerner, R. McLaren, P. K. Quinn, J. M. Roberts, J. Stutz, J. A. Thornton, P. R. Veres, C. Warneke, E. Williams, C. J. Young, B. Yuan, K. J. Zarzana, and S. S. Brown
Atmos. Chem. Phys., 16, 573–583, https://doi.org/10.5194/acp-16-573-2016, https://doi.org/10.5194/acp-16-573-2016, 2016
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High wintertime ozone levels have been observed in the Uintah Basin, Utah, a sparsely populated rural region with intensive oil and gas operations. The reactive nitrogen budget plays an important role in tropospheric ozone formation, and we find that nighttime chemistry has a large effect on its partitioning. Much of the oxidation of reactive nitrogen during a high-ozone year occurred via heterogeneous uptake onto aerosol at night, keeping NOx at concentrations comparable to a low-ozone year.
A. R. Koss, J. de Gouw, C. Warneke, J. B. Gilman, B. M. Lerner, M. Graus, B. Yuan, P. Edwards, S. S. Brown, R. Wild, J. M. Roberts, T. S. Bates, and P. K. Quinn
Atmos. Chem. Phys., 15, 5727–5741, https://doi.org/10.5194/acp-15-5727-2015, https://doi.org/10.5194/acp-15-5727-2015, 2015
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Extraction of natural gas and oil is associated with a range of possible atmospheric environmental issues. Here we present an analysis of gas-phase hydrocarbon measurements taken in an oil and natural gas extraction area in Utah during a period of high wintertime ozone. We are able to constrain important chemical parameters related to emission sources and rates, hydrocarbon photochemistry, and VOC composition.
Y. Liu, B. Yuan, X. Li, M. Shao, S. Lu, Y. Li, C.-C. Chang, Z. Wang, W. Hu, X. Huang, L. He, L. Zeng, M. Hu, and T. Zhu
Atmos. Chem. Phys., 15, 3045–3062, https://doi.org/10.5194/acp-15-3045-2015, https://doi.org/10.5194/acp-15-3045-2015, 2015
B. Yuan, P. R. Veres, C. Warneke, J. M. Roberts, J. B. Gilman, A. Koss, P. M. Edwards, M. Graus, W. C. Kuster, S.-M. Li, R. J. Wild, S. S. Brown, W. P. Dubé, B. M. Lerner, E. J. Williams, J. E. Johnson, P. K. Quinn, T. S. Bates, B. Lefer, P. L. Hayes, J. L. Jimenez, R. J. Weber, R. Zamora, B. Ervens, D. B. Millet, B. Rappenglück, and J. A. de Gouw
Atmos. Chem. Phys., 15, 1975–1993, https://doi.org/10.5194/acp-15-1975-2015, https://doi.org/10.5194/acp-15-1975-2015, 2015
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In this work, secondary formation of formic acid at an urban site and a site in an oil and gas production region is studied. We investigated various gas phase formation pathways of formic acid, including those recently proposed, using a box model. The contributions from aerosol-related processes, fog events and air-snow exchange to formic acid are also quantified.
M. Wang, M. Shao, W. Chen, S. Lu, Y. Liu, B. Yuan, Q. Zhang, Q. Zhang, C.-C. Chang, B. Wang, L. Zeng, M. Hu, Y. Yang, and Y. Li
Atmos. Chem. Phys., 15, 1489–1502, https://doi.org/10.5194/acp-15-1489-2015, https://doi.org/10.5194/acp-15-1489-2015, 2015
C. Warneke, P. Veres, S. M. Murphy, J. Soltis, R. A. Field, M. G. Graus, A. Koss, S.-M. Li, R. Li, B. Yuan, J. M. Roberts, and J. A. de Gouw
Atmos. Meas. Tech., 8, 411–420, https://doi.org/10.5194/amt-8-411-2015, https://doi.org/10.5194/amt-8-411-2015, 2015
R. Ahmadov, S. McKeen, M. Trainer, R. Banta, A. Brewer, S. Brown, P. M. Edwards, J. A. de Gouw, G. J. Frost, J. Gilman, D. Helmig, B. Johnson, A. Karion, A. Koss, A. Langford, B. Lerner, J. Olson, S. Oltmans, J. Peischl, G. Pétron, Y. Pichugina, J. M. Roberts, T. Ryerson, R. Schnell, C. Senff, C. Sweeney, C. Thompson, P. R. Veres, C. Warneke, R. Wild, E. J. Williams, B. Yuan, and R. Zamora
Atmos. Chem. Phys., 15, 411–429, https://doi.org/10.5194/acp-15-411-2015, https://doi.org/10.5194/acp-15-411-2015, 2015
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High 2013 wintertime O3 pollution events associated with oil/gas production within the Uinta Basin are studied using a 3D model. It's able quantitatively to reproduce these events using emission estimates of O3 precursors based on ambient measurements (top-down approach), but unable to reproduce them using a recent bottom-up emission inventory for the oil/gas industry. The role of various physical and meteorological processes, chemical species and pathways contributing to high O3 are quantified.
X. Li, F. Rohrer, T. Brauers, A. Hofzumahaus, K. Lu, M. Shao, Y. H. Zhang, and A. Wahner
Atmos. Chem. Phys., 14, 12291–12305, https://doi.org/10.5194/acp-14-12291-2014, https://doi.org/10.5194/acp-14-12291-2014, 2014
M. Wang, M. Shao, W. Chen, B. Yuan, S. Lu, Q. Zhang, L. Zeng, and Q. Wang
Atmos. Chem. Phys., 14, 5871–5891, https://doi.org/10.5194/acp-14-5871-2014, https://doi.org/10.5194/acp-14-5871-2014, 2014
M. Li, Q. Zhang, D. G. Streets, K. B. He, Y. F. Cheng, L. K. Emmons, H. Huo, S. C. Kang, Z. Lu, M. Shao, H. Su, X. Yu, and Y. Zhang
Atmos. Chem. Phys., 14, 5617–5638, https://doi.org/10.5194/acp-14-5617-2014, https://doi.org/10.5194/acp-14-5617-2014, 2014
K. D. Lu, F. Rohrer, F. Holland, H. Fuchs, T. Brauers, A. Oebel, R. Dlugi, M. Hu, X. Li, S. R. Lou, M. Shao, T. Zhu, A. Wahner, Y. H. Zhang, and A. Hofzumahaus
Atmos. Chem. Phys., 14, 4979–4999, https://doi.org/10.5194/acp-14-4979-2014, https://doi.org/10.5194/acp-14-4979-2014, 2014
W. T. Chen, M. Shao, S. H. Lu, M. Wang, L. M. Zeng, B. Yuan, and Y. Liu
Atmos. Chem. Phys., 14, 3047–3062, https://doi.org/10.5194/acp-14-3047-2014, https://doi.org/10.5194/acp-14-3047-2014, 2014
Z. B. Wang, M. Hu, D. Mogensen, D. L. Yue, J. Zheng, R. Y. Zhang, Y. Liu, B. Yuan, X. Li, M. Shao, L. Zhou, Z. J. Wu, A. Wiedensohler, and M. Boy
Atmos. Chem. Phys., 13, 11157–11167, https://doi.org/10.5194/acp-13-11157-2013, https://doi.org/10.5194/acp-13-11157-2013, 2013
W. W. Hu, M. Hu, B. Yuan, J. L. Jimenez, Q. Tang, J. F. Peng, W. Hu, M. Shao, M. Wang, L. M. Zeng, Y. S. Wu, Z. H. Gong, X. F. Huang, and L. Y. He
Atmos. Chem. Phys., 13, 10095–10112, https://doi.org/10.5194/acp-13-10095-2013, https://doi.org/10.5194/acp-13-10095-2013, 2013
C.-C. Chang, M. Shao, C. C. K. Chou, S.-C. Liu, J.-L. Wang, K.-Z. Lee, C.-H. Lai, T. Zhu, and P.-H. Lin
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-25939-2013, https://doi.org/10.5194/acpd-13-25939-2013, 2013
Revised manuscript not accepted
B. Yuan, W. W. Hu, M. Shao, M. Wang, W. T. Chen, S. H. Lu, L. M. Zeng, and M. Hu
Atmos. Chem. Phys., 13, 8815–8832, https://doi.org/10.5194/acp-13-8815-2013, https://doi.org/10.5194/acp-13-8815-2013, 2013
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Observation and modeling of atmospheric OH and HO2∗ radicals at a subtropical rural site and implications for secondary pollutants
Tracing elevated abundance of CH2Cl2 in the subarctic upper troposphere to the Asian Summer Monsoon
Carbonyl compounds from typical combustion sources: emission characteristics, influencing factors, and their contribution to ozone formation
Formation drivers and photochemical effects of ClNO2 in a coastal city of Southeast China
Significant influence of oxygenated volatile organic compounds on atmospheric chemistry: a case study in a typical industrial city in China
Global ground-based tropospheric ozone measurements: reference data and individual site trends (2000–2022) from the TOAR-II/HEGIFTOM project
Understanding summertime H2O2 chemistry in the North China Plain through observations and modeling studies
Volatile organic compound sources and impacts in an urban Mediterranean area (Marseille, France)
Short-lived organic nitrates in a suburban temperate forest: an indication of efficient assimilation of reactive nitrogen by the biosphere?
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
Marine emissions and trade winds control the atmospheric nitrous oxide in the Galapagos Islands
Measurement report: A complex street-level air quality observation campaign in a heavy-traffic area utilizing the multivariate adaptive regression splines method for field calibration of low-cost sensors
The impact of organic nitrates on summer ozone formation in Shanghai, China
Differences in the key volatile organic compound species between their emitted and ambient concentrations in ozone formation
Tracing Ammonia Emission Sources in California's Salton Sea Region: Insights from Airborne Longwave-Infrared Hyperspectral Imaging and Ground Monitoring
Mechanistic insights into chloroacetic acid production from atmospheric multiphase volatile organic compound–chlorine chemistry
Accurate elucidation of oxidation under heavy ozone pollution: a full suite of radical measurements in the chemically complex atmosphere
Isotopic signatures of methane emission from oil and natural gas plants in southwestern China
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
Airborne quantification of Angolan offshore oil and gas methane emissions
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
Evaluating urban methane emissions and their attributes in a megacity, Osaka, Japan, via mobile and eddy covariance measurements
Ozone (O3) observations in Saxony, Germany for 1997–2020: Trends, modelling and implications for O3 control
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
Hemispheric differences in ozone across the stratosphere-troposphere exchange region
Molecular and seasonal characteristics of organic vapors in urban Beijing: insights from Vocus-PTR measurements
BVOC and speciated monoterpene concentrations and fluxes at a Scandinavian boreal forest
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
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
Ozone deposition measurements over wheat fields in the North China Plain: variability and related factors of deposition flux and velocity
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
Zhouxing Zou, Tianshu Chen, Qianjie Chen, Weihang Sun, Shichun Han, Zhuoyue Ren, Xinyi Li, Wei Song, Aoqi Ge, Qi Wang, Xiao Tian, Chenglei Pei, Xinming Wang, Yanli Zhang, and Tao Wang
Atmos. Chem. Phys., 25, 8147–8161, https://doi.org/10.5194/acp-25-8147-2025, https://doi.org/10.5194/acp-25-8147-2025, 2025
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We measured ambient OH and HO2* (HO2 and contribution from RO2, organic peroxyl radicals) concentrations at a subtropical rural site and compared our observations with model results. During warm periods, the model overestimated concentrations of OH and HO2, leading to overestimation of ozone and nitric acid production. Our findings highlight the need to better understand how OH and HO2 are formed and removed, which is important for accurate air quality and climate predictions.
Markus Jesswein, Valentin Lauther, Nicolas Emig, Peter Hoor, Timo Keber, Hans-Christoph Lachnitt, Linda Ort, Tanja Schuck, Johannes Strobel, Ronja Van Luijt, C. Michael Volk, Franziska Weyland, and Andreas Engel
Atmos. Chem. Phys., 25, 8107–8126, https://doi.org/10.5194/acp-25-8107-2025, https://doi.org/10.5194/acp-25-8107-2025, 2025
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The study investigates transport within the Asian Summer Monsoon, focusing on how CH2Cl2 reaches the subarctic tropopause region. Using data from the PHILEAS campaign in 2023, events with increased mixing ratios were detected. Their origin, the transport paths to the tropopause region, and the potential entry into the stratosphere were analyzed. The East Asian Summer Monsoon was identified as the main transport pathway, with only a small contribution to the stratosphere in the following days.
Yanjie Lu, Xinxin Feng, Yanli Feng, Minjun Jiang, Yu Peng, Tian Chen, and Yingjun Chen
Atmos. Chem. Phys., 25, 8043–8059, https://doi.org/10.5194/acp-25-8043-2025, https://doi.org/10.5194/acp-25-8043-2025, 2025
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Through lab tests and field measurements from typical sources, we found that carbonyl compounds from biomass burning are an order of magnitude higher than those from vehicles. The formation of carbonyl compounds in solid and liquid fuel is governed by combustion temperature and emission standards, respectively. Fuel type determines the chemical composition. Biomass burning and farm machinery are key drivers of atmospheric oxidation capacity. This study provides actionable solutions to safeguard public health.
Gaojie Chen, Xiaolong Fan, Haichao Wang, Yee Jun Tham, Ziyi Lin, Xiaoting Ji, Lingling Xu, Baoye Hu, and Jinsheng Chen
Atmos. Chem. Phys., 25, 7815–7828, https://doi.org/10.5194/acp-25-7815-2025, https://doi.org/10.5194/acp-25-7815-2025, 2025
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Our study revealed that the nighttime heterogeneous dinitrogen pentoxide (N2O5) uptake process was the major contributor of nitryl chloride (ClNO2) sources, while nitrate photolysis may promote the elevation of daytime ClNO2 concentrations. The rates of alkane oxidation by chlorine (Cl) radical in the early morning exceeded those by OH radical, significantly promoted the formation of ROx and ozone (O3), and further enhanced the atmospheric oxidation capacity levels.
Jingwen Dai, Kun Zhang, Yanli Feng, Xin Yi, Rui Li, Jin Xue, Qing Li, Lishu Shi, Jiaqiang Liao, Yanan Yi, Fangting Wang, Liumei Yang, Hui Chen, Ling Huang, Jiani Tan, Yangjun Wang, and Li Li
Atmos. Chem. Phys., 25, 7467–7484, https://doi.org/10.5194/acp-25-7467-2025, https://doi.org/10.5194/acp-25-7467-2025, 2025
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Oxygenated volatile organic compounds (OVOCs) are important ozone (O3) precursors. However, most O3 formation analysis based on the box model (OBM) does not include any OVOC constraint. To access the interference of OVOCs with O3 simulation, this study presents results from a field campaign and OBM analysis. Our results indicate that no OVOC constraint in the OBM can lead to overestimation of OVOCs, free radicals, and O3.
Roeland Van Malderen, Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Herman G. J. Smit, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, David W. Tarasick, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Stéphanie Evan, Victoria Flood, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Marco Iarlori, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Glen McConville, Katrin Müller, Tomoo Nagahama, Justus Notholt, Ankie Piters, Natalia Prats, Richard Querel, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 7187–7225, https://doi.org/10.5194/acp-25-7187-2025, https://doi.org/10.5194/acp-25-7187-2025, 2025
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Tropospheric ozone is an important greenhouse gas and is an air pollutant. The time variability of tropospheric ozone is mainly driven by anthropogenic emissions. In this paper, we study the distribution and time variability of ozone from harmonized ground-based observations from five different measurement techniques. Our findings provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
Can Ye, Pengfei Liu, Chaoyang Xue, Chenglong Zhang, Zhuobiao Ma, Chengtang Liu, Junfeng Liu, Keding Lu, Yujing Mu, and Yuanhang Zhang
Atmos. Chem. Phys., 25, 6991–7005, https://doi.org/10.5194/acp-25-6991-2025, https://doi.org/10.5194/acp-25-6991-2025, 2025
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This study investigates H2O2 chemistry in rural North China. The observed H2O2 showed distinct diurnal variations influenced by photochemical reactions. A box model revealed that H2O2 is primarily produced by HO2 recombination and removed mainly via particle uptake. Reductions in NOx, PM2.5, and alkanes raised H2O2 levels, while cutting alkenes, aromatics, CO, and HONO lowered them. A dual strategy focusing on VOC and NOx control is essential to reduce both H2O2 and ozone pollution.
Marvin Dufresne, Thérèse Salameh, Thierry Leonardis, Grégory Gille, Alexandre Armengaud, and Stéphane Sauvage
Atmos. Chem. Phys., 25, 5977–5999, https://doi.org/10.5194/acp-25-5977-2025, https://doi.org/10.5194/acp-25-5977-2025, 2025
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This paper discusses the 18-month-long measurement of non-methane hydrocarbons (NMHCs) in Marseille, where there was no measurement since early 2000, despite the impact of NMHCs on air quality and climate. Traffic-related sources are the largest contributor to NMHC concentrations in Marseille, and shipping strongly contributes to the formation of aerosols. Finally, the Covid-19 lockdown had an impact on NMHC concentrations, reaching a 50 % decrease for traffic-related sources.
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
Atmos. Chem. Phys., 25, 5893–5909, https://doi.org/10.5194/acp-25-5893-2025, https://doi.org/10.5194/acp-25-5893-2025, 2025
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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, for example, alkyl nitrates and peroxy nitrates.
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
Atmos. Chem. Phys., 25, 4965–4988, https://doi.org/10.5194/acp-25-4965-2025, https://doi.org/10.5194/acp-25-4965-2025, 2025
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Methane (CH4) is a potent greenhouse gas. Northern China contributes a large proportion of CH4 emissions, yet large observation gaps exist. Here we compiled a comprehensive dataset, which is publicly available, that includes 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.
Timur Cinay, Dickon Young, Nazaret Narváez Jimenez, Cristina Vintimilla-Palacios, Ariel Pila Alonso, Paul B. Krummel, William Vizuete, and Andrew R. Babbin
Atmos. Chem. Phys., 25, 4703–4718, https://doi.org/10.5194/acp-25-4703-2025, https://doi.org/10.5194/acp-25-4703-2025, 2025
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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 the coastal upwelling systems of Peru and Chile.
Petra Bauerová, Josef Keder, Adriana Šindelářová, Ondřej Vlček, William Patiño, Pavel Krč, Jan Geletič, Hynek Řezníček, Martin Bureš, Kryštof Eben, Michal Belda, Jelena Radović, Vladimír Fuka, Radek Jareš, Igor Esau, and Jaroslav Resler
Atmos. Chem. Phys., 25, 4477–4504, https://doi.org/10.5194/acp-25-4477-2025, https://doi.org/10.5194/acp-25-4477-2025, 2025
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The study explored urban air quality in Prague using low-cost sensors and highlighted the multivariate adaptive regression splines (MARS) correction method's effectiveness in enhancing accuracy. Results showed traffic's impact on nitrogen dioxide levels and atmospheric dynamics on particulate matter. The research confirmed MARS-corrected sensors as cost-effective for monitoring, despite challenges like sensor ageing and data quality control.
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
Atmos. Chem. Phys., 25, 3905–3918, https://doi.org/10.5194/acp-25-3905-2025, https://doi.org/10.5194/acp-25-3905-2025, 2025
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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 homemade thermal dissociation cavity-enhanced absorption spectroscopy (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 field observations in conjunction with model simulations.
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.
Sina Hasheminassab, David M. Tratt, Olga V. Kalashnikova, Clement S. Chang, Morad Alvarez, Kerry N. Buckland, Michael J. Garay, Francesca M. Hopkins, Eric R. Keim, Le Kuai, Yaning Miao, Payam Pakbin, William C. Porter, and Mohammad H. Sowlat
EGUsphere, https://doi.org/10.5194/egusphere-2025-1378, https://doi.org/10.5194/egusphere-2025-1378, 2025
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Ammonia (NH3) is a key air pollutant linked to fine particle pollution, yet its sources remain poorly understood. Using airborne infrared imaging and ground sensors, we mapped NH3 emissions in California’s Salton Sea region with unprecedented detail. We found high emissions from farms, geothermal plants, and waste sites, including sources missing from inventories. These findings highlight the need for better NH3 monitoring to improve air quality models and guide pollution reduction strategies.
Mingxue Li, Men Xia, Chunshui Lin, Yifan Jiang, Weihang Sun, Yurun Wang, Yingnan Zhang, Maoxia He, and Tao Wang
Atmos. Chem. Phys., 25, 3753–3764, https://doi.org/10.5194/acp-25-3753-2025, https://doi.org/10.5194/acp-25-3753-2025, 2025
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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.
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.
Dingxi Chen, Yi Liu, Zetong Niu, Ao Wang, Pius Otwil, Yuanyuan Huang, Zhongcong Sun, Xiaobing Pang, Liyang Zhan, and Longfei Yu
EGUsphere, https://doi.org/10.5194/egusphere-2025-377, https://doi.org/10.5194/egusphere-2025-377, 2025
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We carried out studies at 11 oil and gas sites in Southwest China (an important natural gas production area), investigating the methane concentration distribution pattern and emission inventory of oil and gas industrial sites through a combination of ground monitoring and drone airborne monitoring techniques, and at the same time, utilizing stable isotope techniques to trace back the methane from the oil and gas sites.
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.
Alina Fiehn, Maximilian Eckl, Magdalena Pühl, Tiziana Bräuer, Klaus-Dirk Gottschaldt, Heinfried Aufmhoff, Lisa Eirenschmalz, Gregor Neumann, Felicitas Sakellariou, Daniel Sauer, Robert Baumann, Guilherme De Aguiar Ventura, Winne Nayole Cadete, Dário Luciano Zua, Manuel Xavier, Paulo Correia, and Anke Roiger
EGUsphere, https://doi.org/10.5194/egusphere-2025-635, https://doi.org/10.5194/egusphere-2025-635, 2025
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In September 2022, the METHANE-To-Go Africa (MTGA) campaign, part of UNEP’s IMEO Methane Science Studies, conducted the first CH₄ emissions measurements from West Africa’s offshore oil and gas sector. Using an aircraft-based mass balance method, emissions from Angolan offshore facilities were quantified. Older, low-producing facilities showed higher emissions than newer ones. High-emission events were observed, highlighting the need for targeted monitoring and mitigation efforts.
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.
Masahito Ueyama, Taku Umezawa, Yukio Terao, Mark Lunt, and James Lawrence France
EGUsphere, https://doi.org/10.5194/egusphere-2024-3926, https://doi.org/10.5194/egusphere-2024-3926, 2025
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Methane (CH4) emissions were measured in Megacity Osaka, Japan, using mobile and eddy covariance methods. The CH4 emissions were much higher than those reported in local inventories, with natural gas contributing up to 74 % of the emissions. Several CH4 sources not accounted for in current inventories were identified. These results emphasize the need for more comprehensive emissions tracking in urban areas to enhance climate change mitigation efforts.
Yaru Wang, Dominik van Pinxteren, Andreas Tilgner, Erik Hans Hoffmann, Max Hell, Susanne Bastian, and Hartmut Herrmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-4202, https://doi.org/10.5194/egusphere-2024-4202, 2025
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Tropospheric ground-level ozone (O3) is a global air-quality pollutant and greenhouse gas. Long-term O3 trends from 16 stations in Saxony, Germany, were compared over three periods, revealing worsened O3 pollution over the last decade. O3 formation has been volatile organic compound (VOC)-limited at traffic and urban sites for the past 20 years. To mitigate O3 pollution, moderate nitrogen oxides and additional VOC controls, particularly in solvent use, should be prioritized in the coming years.
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.
Rodrigo J. Seguel, Charlie Opazo, Yann Cohen, Owen R. Cooper, Laura Gallardo, Björn-Martin Sinnhuber, Florian Obersteiner, Andreas Zahn, Peter Hoor, and Susanne Rohs
EGUsphere, https://doi.org/10.5194/egusphere-2024-3719, https://doi.org/10.5194/egusphere-2024-3719, 2024
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We explored differences in ozone levels between the Northern and Southern Hemispheres in the Stratosphere-troposphere exchange region. Using unique data from a research aircraft, we found significantly lower ozone levels (with stratospheric character) in the Southern Hemisphere, especially during years of severe ozone depletion. A Sudden Stratospheric Warming event in 2019 increased Southern Hemisphere ozone levels, highlighting the relationship between atmospheric events and ozone distribution.
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.
Ross Charles Petersen, Thomas Holst, Cheng Wu, Radovan Krejci, Jeremy Chan, Claudia Mohr, and Janne Rinne
EGUsphere, https://doi.org/10.5194/egusphere-2024-3410, https://doi.org/10.5194/egusphere-2024-3410, 2024
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Ecosystem-scale emissions of biogenic volatile organic compounds (BVOCs) are important for atmospheric chemistry. Here we investigate boreal BVOC fluxes from a forest in central Sweden. BVOC fluxes were measured above-canopy using proton-transfer-reaction mass spectrometry, while compound-specific monoterpene (MT) fluxes were assessed using a concentration gradient method. We also evaluate the impact of chemical degradation on observed sesquiterpene (SQT) and nighttime MT fluxes.
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.
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.
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.
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.
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