Articles | Volume 20, issue 24
https://doi.org/10.5194/acp-20-15969-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-20-15969-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Measurement report
| 
22 Dec 2020
Measurement report |
| 22 Dec 2020
| 22 Dec 2020
Measurement report: Long-term variations in carbon monoxide at a background station in China's Yangtze River Delta region
Yijing Chen
College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
School of Environment, Tsinghua University, Beijing 100084, China
Qianli Ma
Lin'an Atmosphere Background National Observation and Research
Station, Lin'an 311307, Hangzhou, China
College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
Xiaobin Xu
Key Laboratory for Atmospheric Chemistry, Chinese Academy of
Meteorological Sciences, Beijing 100081, China
Jie Yao
Lin'an Atmosphere Background National Observation and Research
Station, Lin'an 311307, Hangzhou, China
Wei Gao
Shanghai Key Laboratory of Meteorology and Health, Shanghai
Meteorological Service, Shanghai 200030, China
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Atmos. Chem. Phys., 24, 9355–9368, https://doi.org/10.5194/acp-24-9355-2024, https://doi.org/10.5194/acp-24-9355-2024, 2024
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Atmos. Chem. Phys., 24, 3759–3768, https://doi.org/10.5194/acp-24-3759-2024, https://doi.org/10.5194/acp-24-3759-2024, 2024
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Jiyuan Yang, Guoyang Lei, Jinfeng Zhu, Yutong Wu, Chang Liu, Kai Hu, Junsong Bao, Zitong Zhang, Weili Lin, and Jun Jin
Atmos. Chem. Phys., 24, 123–136, https://doi.org/10.5194/acp-24-123-2024, https://doi.org/10.5194/acp-24-123-2024, 2024
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The atmospheric pollution and formation mechanisms of particulate-bound alkyl nitrate in Beijing were studied. C9–C16 long-chain n-alkyl nitrates negatively correlated with O3 but positively correlated with PM2.5 and NO2, so they may not be produced during gas-phase homogeneous reactions in the photochemical process but form through reactions between alkanes and nitrates on PM surfaces. Particulate-bound n-alkyl nitrates strongly affect both haze pollution and atmospheric visibility.
Xiaoxiao Li, Yijing Chen, Yuyang Li, Runlong Cai, Yiran Li, Chenjuan Deng, Jin Wu, Chao Yan, Hairong Cheng, Yongchun Liu, Markku Kulmala, Jiming Hao, James N. Smith, and Jingkun Jiang
Atmos. Chem. Phys., 23, 14801–14812, https://doi.org/10.5194/acp-23-14801-2023, https://doi.org/10.5194/acp-23-14801-2023, 2023
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Near-continuous measurements show the composition, sources, and seasonal variations of ultrafine particles (UFPs) in urban Beijing. Vehicle and cooking emissions and new particle formation are the main sources of UFPs, and aqueous/heterogeneous processes increase UFP mode diameters. UFPs are the highest in winter due to the highest primary particle emission rates and new particle formation rates, and CHO fractions are the highest in summer due to the strongest photooxidation.
Chunxiang Ye, Shuzheng Guo, Weili Lin, Fangjie Tian, Jianshu Wang, Chong Zhang, Suzhen Chi, Yi Chen, Yingjie Zhang, Limin Zeng, Xin Li, Duo Bu, Jiacheng Zhou, and Weixiong Zhao
Atmos. Chem. Phys., 23, 10383–10397, https://doi.org/10.5194/acp-23-10383-2023, https://doi.org/10.5194/acp-23-10383-2023, 2023
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Atmos. Chem. Phys., 23, 7635–7652, https://doi.org/10.5194/acp-23-7635-2023, https://doi.org/10.5194/acp-23-7635-2023, 2023
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Atmos. Chem. Phys., 23, 3015–3029, https://doi.org/10.5194/acp-23-3015-2023, https://doi.org/10.5194/acp-23-3015-2023, 2023
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Atmos. Chem. Phys., 23, 1329–1343, https://doi.org/10.5194/acp-23-1329-2023, https://doi.org/10.5194/acp-23-1329-2023, 2023
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The particle matter (PM2.5) at the top of the 632 m high Shanghai Tower was found to be higher than the surface from June to October due to unexpected larger PM2.5 levels during early to middle afternoon at Shanghai Tower. We suppose the significant chemical production of secondary species existed in the mid-upper planetary boundary layer. We found a high nitrate concentration at the tower site for both daytime and nighttime in winter, implying efficient gas-phase and heterogeneous formation.
Chenhong Zhou, Fan Wang, Yike Guo, Cheng Liu, Dongsheng Ji, Yuesi Wang, Xiaobin Xu, Xiao Lu, Yan Wang, Gregory Carmichael, and Meng Gao
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-187, https://doi.org/10.5194/essd-2022-187, 2022
Manuscript not accepted for further review
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We develop an eXtreme Gradient Boosting (XGBoost) model integrating high-resolution meteorological data, satellite retrievals of trace gases, etc. to provide reconstructed daily ground-level O3 over 2005–2021 in China. It can facilitate climatological, ecological, and health research. The dataset is freely available at Zenodo (https://zenodo.org/record/6507706#.Yo8hKujP13g; Zhou, 2022).
Xueli Liu, Liang Ran, Weili Lin, Xiaobin Xu, Zhiqiang Ma, Fan Dong, Di He, Liyan Zhou, Qingfeng Shi, and Yao Wang
Atmos. Chem. Phys., 22, 7071–7085, https://doi.org/10.5194/acp-22-7071-2022, https://doi.org/10.5194/acp-22-7071-2022, 2022
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Significant decreases in annual mean NOx from 2011 to 2016 and SO2 from 2008 to 2016 confirm the effectiveness of relevant control measures on the reduction in NOx and SO2 emissions in the North China Plain (NCP). NOx at SDZ had a weaker influence than SO2 on the emission reduction in Beijing and other areas in the NCP. An increase in the number of motor vehicles and weak traffic restrictions have caused vehicle emissions of NOx, which indicates that NOx emission control should be strengthened.
Qingqing Yin, Qianli Ma, Weili Lin, Xiaobin Xu, and Jie Yao
Atmos. Chem. Phys., 22, 1015–1033, https://doi.org/10.5194/acp-22-1015-2022, https://doi.org/10.5194/acp-22-1015-2022, 2022
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China has been experiencing rapid changes in emissions of air pollutants in recent decades. NOx and SO2 measurements from 2006 to 2016 at the Lin’an World Meteorological Organization Global Atmospheric Watch station were used to characterize the seasonal and diurnal variations and study the long-term trends. This study reaffirms China’s success in controlling both NOx and SO2 in the Yangtze River Delta but indicates at the same time a necessity to strengthen the NOx emission control.
Tongqiang Liu, Qianshan He, Yonghang Chen, Jie Liu, Qiong Liu, Wei Gao, Guan Huang, Wenhao Shi, and Xiaohong Yu
Atmos. Chem. Phys., 21, 5377–5391, https://doi.org/10.5194/acp-21-5377-2021, https://doi.org/10.5194/acp-21-5377-2021, 2021
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The variation in aerosol 355 nm lidar ratio and its influence factors were analyzed in Shanghai. About 90 % of the lidar ratio was distributed in 10 sr–80 sr, with an average of 41.0±22.5 sr, and the lidar ratio decreased with the increase in height. Due to aerosol radiative effects, the vertical slope of the lidar ratio presented a decreasing trend with increasing atmospheric turbidity. A large lidar ratio above 1 km was related to biomass burning aerosols and high relative humidity.
Ziru Lan, Weili Lin, Weiwei Pu, and Zhiqiang Ma
Atmos. Chem. Phys., 21, 4561–4573, https://doi.org/10.5194/acp-21-4561-2021, https://doi.org/10.5194/acp-21-4561-2021, 2021
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Haze related to particulate matter has become a big problem in eastern China, and ammonia (NH3) plays an important role in secondary particulate matter formation. In this work, variations in the NH3 mixing ratio showed that the contributions of NH3 sources and sinks in urban and suburban areas were quite different, although the areas were under the influence of similar weather systems. This study furthers the understanding of the behavior of NH3 in a megacity environment.
Weili Lin, Feng Wang, Chunxiang Ye, and Tong Zhu
The Cryosphere Discuss., https://doi.org/10.5194/tc-2021-32, https://doi.org/10.5194/tc-2021-32, 2021
Preprint withdrawn
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Field observations found that released NOx on the glacier surface of the Tibetan Plateau, an important snow-covered region in the northern mid-latitudes, had a higher concentration than in Antarctic and Arctic regions. Such evidence, and such high fluxes as observed here on the Tibetan plateau is novel. That such high concentrations of nitrogen oxides can be found in remote areas is interesting and important for the oxidative budget of the boundary layer.
Yixuan Gu, Fengxia Yan, Jianming Xu, Yuanhao Qu, Wei Gao, Fangfang He, and Hong Liao
Atmos. Chem. Phys., 20, 14361–14375, https://doi.org/10.5194/acp-20-14361-2020, https://doi.org/10.5194/acp-20-14361-2020, 2020
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High levels and statistically insignificant changes of ozone are detected at a remote monitoring site on Sheshan Island in Shanghai, China, from 2012 to 2017; 6-year observations suggest regional transport exerted minimum influence on the offshore oceanic air in September and October. Both city plumes and oceanic air inflows could contribute to ozone enhancements in Shanghai, and the latter are found to lead to 20–30 % increases in urban ozone concentrations based on WRF-Chem simulations.
Tao Ma, Hiroshi Furutani, Fengkui Duan, Takashi Kimoto, Jingkun Jiang, Qiang Zhang, Xiaobin Xu, Ying Wang, Jian Gao, Guannan Geng, Meng Li, Shaojie Song, Yongliang Ma, Fei Che, Jie Wang, Lidan Zhu, Tao Huang, Michisato Toyoda, and Kebin He
Atmos. Chem. Phys., 20, 5887–5897, https://doi.org/10.5194/acp-20-5887-2020, https://doi.org/10.5194/acp-20-5887-2020, 2020
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The formation mechanisms of organic matter and sulfate in winter haze in the North China Plain remain unclear. This paper presents the identification and quantification of hydroxymethanesulfonate (HMS) in PM2.5 in Beijing winter and elucidates the heterogeneous HMS chemistry in favorable winter haze conditions. We show that the HMS not only contributes a substantial mass of organic matter, but also leads to an overestimation of sulfate in conventional measurements.
Sinikka T. Lennartz, Christa A. Marandino, Marc von Hobe, Meinrat O. Andreae, Kazushi Aranami, Elliot Atlas, Max Berkelhammer, Heinz Bingemer, Dennis Booge, Gregory Cutter, Pau Cortes, Stefanie Kremser, Cliff S. Law, Andrew Marriner, Rafel Simó, Birgit Quack, Günther Uher, Huixiang Xie, and Xiaobin Xu
Earth Syst. Sci. Data, 12, 591–609, https://doi.org/10.5194/essd-12-591-2020, https://doi.org/10.5194/essd-12-591-2020, 2020
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Sulfur-containing trace gases in the atmosphere influence atmospheric chemistry and the energy budget of the Earth by forming aerosols. The ocean is an important source of the most abundant sulfur gas in the atmosphere, carbonyl sulfide (OCS) and its most important precursor carbon disulfide (CS2). In order to assess global variability of the sea surface concentrations of both gases to calculate their oceanic emissions, we have compiled a database of existing shipborne measurements.
Wanyun Xu, Ye Kuang, Chunsheng Zhao, Jiangchuan Tao, Gang Zhao, Yuxuan Bian, Wen Yang, Yingli Yu, Chuanyang Shen, Linlin Liang, Gen Zhang, Weili Lin, and Xiaobin Xu
Atmos. Chem. Phys., 19, 10557–10570, https://doi.org/10.5194/acp-19-10557-2019, https://doi.org/10.5194/acp-19-10557-2019, 2019
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The study of HONO, the primary source of OH radicals, is crucial for atmospheric photochemistry and heterogeneous chemistry. Heterogeneous NO2 conversion was shown to be one of the missing sources of HONO on the North China Plain, but the reaction path is still under debate. In this work, evidence was found that NH3 was the key factor that promoted the hydrolysis of NO2, leading to the explosive growth of HONO and nitrate, suggesting that NH3 emission control measures are urgently needed.
Jianming Xu, Xuexi Tie, Wei Gao, Yanfen Lin, and Qingyan Fu
Atmos. Chem. Phys., 19, 9017–9035, https://doi.org/10.5194/acp-19-9017-2019, https://doi.org/10.5194/acp-19-9017-2019, 2019
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The PM2.5 in China has decreased significantly in recent years as a result of the implementation of the Chinese Clean Air Action Plan in 2013, while the O3 pollution is getting worse, especially in megacities. The work aims to better understand the elevated O3 pollution in the megacity of Shanghai, China, and its response to emission changes, which is important for developing an effective emission control strategy in the future.
Qianshan He, Jianzhong Ma, Xiangdong Zheng, Xiaolu Yan, Holger Vömel, Frank G. Wienhold, Wei Gao, Dongwei Liu, Guangming Shi, and Tiantao Cheng
Atmos. Chem. Phys., 19, 8399–8406, https://doi.org/10.5194/acp-19-8399-2019, https://doi.org/10.5194/acp-19-8399-2019, 2019
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An enhanced aerosol layer in the upper troposphere--lower stratosphere was observed by a COBALD over the Tibetan Plateau, in the summer of 2014. The color index of the enhanced aerosol layer indicates the prevalence of dominant fine particles with a mode radius < 0.1 μm. Unlike the very small particles at low relative humidity (RHi < 40%), the relatively large particles in the aerosol layer were generally very hydrophilic as their size increased dramatically with relative humidity.
Shaojie Song, Meng Gao, Weiqi Xu, Yele Sun, Douglas R. Worsnop, John T. Jayne, Yuzhong Zhang, Lei Zhu, Mei Li, Zhen Zhou, Chunlei Cheng, Yibing Lv, Ying Wang, Wei Peng, Xiaobin Xu, Nan Lin, Yuxuan Wang, Shuxiao Wang, J. William Munger, Daniel J. Jacob, and Michael B. McElroy
Atmos. Chem. Phys., 19, 1357–1371, https://doi.org/10.5194/acp-19-1357-2019, https://doi.org/10.5194/acp-19-1357-2019, 2019
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Chemistry responsible for sulfate production in northern China winter haze remains mysterious. We propose a potentially key pathway through the reaction of formaldehyde and sulfur dioxide that has not been accounted for in previous studies. The special atmospheric conditions favor the formation and existence of their complex, hydroxymethanesulfonate (HMS).
Ruijing Ni, Jintai Lin, Yingying Yan, and Weili Lin
Atmos. Chem. Phys., 18, 11447–11469, https://doi.org/10.5194/acp-18-11447-2018, https://doi.org/10.5194/acp-18-11447-2018, 2018
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By integrating several modeling methods, we find considerable contributions of foreign anthropogenic emissions to surface ozone over China (2–11 ppb). For anthropogenic ozone over China, the foreign contribution is 40–50 % below 2 km and 85 % in the upper troposphere. For total foreign anthropogenic ozone over China, the portion of transboundary ozone produced within foreign emission source regions is less than 50 %, with the rest produced by precursors transported out of those source regions.
Yi Tang, Shuxiao Wang, Qingru Wu, Kaiyun Liu, Long Wang, Shu Li, Wei Gao, Lei Zhang, Haotian Zheng, Zhijian Li, and Jiming Hao
Atmos. Chem. Phys., 18, 8279–8291, https://doi.org/10.5194/acp-18-8279-2018, https://doi.org/10.5194/acp-18-8279-2018, 2018
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In this study, 3-year measurements of atmospheric Hg were carried out at a rural site in East China. A significant downward trend was observed during the sampling period. This study used a new approach that considers both cluster frequency and the Hg concentration associated with each cluster, and we calculated that atmospheric Hg from the whole region of China has caused a 70 % decline of GEM concentration at the Chongming monitoring site due to strict air pollution control policies in China.
Xiaobin Xu, Hualong Zhang, Weili Lin, Ying Wang, Wanyun Xu, and Shihui Jia
Atmos. Chem. Phys., 18, 5199–5217, https://doi.org/10.5194/acp-18-5199-2018, https://doi.org/10.5194/acp-18-5199-2018, 2018
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We present the first simultaneous PAN and O3 measurements from the central Tibetan Plateau. Both gases showed unique diurnal cycles with steep rises in the early morning and broader daytime platforms, which is attributed to the PBL evolution. Some high PAN and O3 episodes were observed and caused either by long-range transport of pollutants from south Asia or by downward transport of air masses from the upper troposphere, indicating the dynamic impacts on tropospheric chemistry over the Tibet.
Wanyun Xu, Xiaobin Xu, Meiyun Lin, Weili Lin, David Tarasick, Jie Tang, Jianzhong Ma, and Xiangdong Zheng
Atmos. Chem. Phys., 18, 773–798, https://doi.org/10.5194/acp-18-773-2018, https://doi.org/10.5194/acp-18-773-2018, 2018
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The impact of anthropogenic emissions and climate variability on the long-term trends and periodicity of surface ozone measured at Mt Waliguan (WLG) for the period of 1994–2013 is studied. STT ozone and rising emissions in eastern China contribute to spring and autumnal increasing trends, respectively. The 2–3-, 3–7-, and 11-year periodicities in the ozone data are linked to the QBO, EASMI, and sunspot cycle, respectively. An empirical model is obtained for normalised monthly ozone at WLG.
Zhaoyang Meng, Xiaobin Xu, Weili Lin, Baozhu Ge, Yulin Xie, Bo Song, Shihui Jia, Rui Zhang, Wei Peng, Ying Wang, Hongbing Cheng, Wen Yang, and Huarong Zhao
Atmos. Chem. Phys., 18, 167–184, https://doi.org/10.5194/acp-18-167-2018, https://doi.org/10.5194/acp-18-167-2018, 2018
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This paper presents simultaneous measurements of NH3, other trace gases, and water-soluble ions in PM2.5 from May to September 2013 at a rural site in the North China Plain. Atmospheric ammonia and related parameters are characterised and the impact of ammonia on formation of secondary aerosols is investigated. The results presented in this paper may improve our understanding of the role of ammonia in aerosol formation.
Rui Wang, Xiaobin Xu, Shihui Jia, Ruisheng Ma, Liang Ran, Zhaoze Deng, Weili Lin, Ying Wang, and Zhiqiang Ma
Atmos. Chem. Phys., 17, 3891–3903, https://doi.org/10.5194/acp-17-3891-2017, https://doi.org/10.5194/acp-17-3891-2017, 2017
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Knowledge about the vertical distributions of air pollutants is limited. We present first unmanned aerial vehicle (UAV) observations of vertical profiles of O3 and size-resolved aerosol number concentrations over a rural site in the North China Plain. We show the determination of mixed and residual layer depth and characterization of diurnal O3 and aerosol number concentrations in the mixed and residual layer. We confirm a rapid increase of O3 in the lower troposphere during the recent decade.
Yingruo Li, Chunxiang Ye, Jun Liu, Yi Zhu, Junxia Wang, Ziqiang Tan, Weili Lin, Limin Zeng, and Tong Zhu
Atmos. Chem. Phys., 16, 14265–14283, https://doi.org/10.5194/acp-16-14265-2016, https://doi.org/10.5194/acp-16-14265-2016, 2016
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We developed the surface flux intensity calculation method based on 2-year continuous ground measurement at a cross-boundary site between Beijing and the NCP to investigate the surface regional transport. The long-term and multispecies observation demonstrated the regional transport influence of the megacity Beijing and the NCP on Yufa. Our study has a direct implication in air quality control measures implemented in Beijing and its surrounding areas.
Liang Ran, Zhaoze Deng, Xiaobin Xu, Peng Yan, Weili Lin, Ying Wang, Ping Tian, Pucai Wang, Weilin Pan, and Daren Lu
Atmos. Chem. Phys., 16, 10441–10454, https://doi.org/10.5194/acp-16-10441-2016, https://doi.org/10.5194/acp-16-10441-2016, 2016
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Vertical profiles of black carbon within 1 km above the ground were measured using a micro-aethalometer attached to a tethered balloon during the VOGA field campaign in summer 2014 at a semirural site in the North China Plain. The diurnal cycle of black carbon vertical distributions following the development of the mixing layer was analyzed for a selected dataset of 67 profiles.
Wanyun Xu, Weili Lin, Xiaobin Xu, Jie Tang, Jianqing Huang, Hao Wu, and Xiaochun Zhang
Atmos. Chem. Phys., 16, 6191–6205, https://doi.org/10.5194/acp-16-6191-2016, https://doi.org/10.5194/acp-16-6191-2016, 2016
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Long-term characteristics and trends of baseline surface ozone concentration at Waliguan station in western China for the period of 1994 to 2013 were analysed, using a modified Mann–Kendall test and the Hilbert–Huang transform analysis for the trend and periodicity analysis, respectively. Significant increasing trends were detected in all seasons, except for summer. The non-linearity caused by the interannual variation of ozone concentrations is evident, showing a 2–4-year, 7- and 11-year periodicity.
Zhiqiang Ma, Jing Xu, Weijun Quan, Ziyin Zhang, Weili Lin, and Xiaobin Xu
Atmos. Chem. Phys., 16, 3969–3977, https://doi.org/10.5194/acp-16-3969-2016, https://doi.org/10.5194/acp-16-3969-2016, 2016
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In this paper, we find that the daily maximum 8 h O3 in the eastern China has undergone a significant increase during 2003–2015, with a rate of 1.1 ppb per year. The increase of surface ozone was mainly induced by the emission changes and the meteorological factors just played a tiny negative influence. Our result also indicates that VOCs seem to play more important role in the ozone increase than the effect of NO titration.
L. Zhang, J. Y. Sun, X. J. Shen, Y. M. Zhang, H. Che, Q. L. Ma, Y. W. Zhang, X. Y. Zhang, and J. A. Ogren
Atmos. Chem. Phys., 15, 8439–8454, https://doi.org/10.5194/acp-15-8439-2015, https://doi.org/10.5194/acp-15-8439-2015, 2015
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The aerosol hygroscopic properties at a rural background site in the Yangtze River delta of China was discussed. The results show the scattering coefficient and backscattering coefficient increased by 58 and 25% as relative humidity (RH) increased from 40 to 85%, while the hemispheric backscatter fraction decreased by 21%. Aerosol hygroscopic growth caused a 47% increase in calculated aerosol direct radiative forcing at 85% RH compared to the forcing at 40% RH. Nitrate played a vital role.
L. Ran, W. L. Lin, Y. Z. Deji, B. La, P. M. Tsering, X. B. Xu, and W. Wang
Atmos. Chem. Phys., 14, 10721–10730, https://doi.org/10.5194/acp-14-10721-2014, https://doi.org/10.5194/acp-14-10721-2014, 2014
W. Y. Xu, C. S. Zhao, L. Ran, W. L. Lin, P. Yan, and X. B. Xu
Atmos. Chem. Phys., 14, 7757–7768, https://doi.org/10.5194/acp-14-7757-2014, https://doi.org/10.5194/acp-14-7757-2014, 2014
J. Ma, W. L. Lin, X. D. Zheng, X. B. Xu, Z. Li, and L. L Yang
Atmos. Chem. Phys., 14, 5311–5325, https://doi.org/10.5194/acp-14-5311-2014, https://doi.org/10.5194/acp-14-5311-2014, 2014
H. Zhang, X. Xu, W. Lin, and Y. Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-12-31871-2012, https://doi.org/10.5194/acpd-12-31871-2012, 2012
Revised manuscript not accepted
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
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
Mechanistic insights into chloroacetic acid production from atmospheric multiphase volatile organic compound–chlorine chemistry
Understanding summertime H2O2 chemistry in North China Plain through observations and modelling studies
Accurate elucidation of oxidation under heavy ozone pollution: a full suite of radical measurements in the chemically complex atmosphere
Carbonyl compounds from typical combustion sources: emission characteristics, influencing factors, and their contribution to ozone formation
Emissions of intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from different cumulative-mileage diesel vehicles at various ambient temperatures
Characterization of nitrous acid and its potential effects on secondary pollution in the warm season in Beijing urban areas
Vertical changes in volatile organic compounds (VOCs) and impacts on photochemical ozone formation
Diurnal, seasonal, and interannual variations in δ(18O) of atmospheric O2 and its application to evaluate natural and anthropogenic changes in oxygen, carbon, and water cycles
Cloud processing of dimethyl sulfide (DMS) oxidation products limits sulfur dioxide (SO2) and carbonyl sulfide (OCS) production in the eastern North Atlantic marine boundary layer
Atmospheric carbonyl compounds are crucial in regional ozone heavy pollution: insights from the Chengdu Plain Urban Agglomeration, China
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
Global Ground-based Tropospheric Ozone Measurements: Reference Data and Individual Site Trends (2000–2022) from the TOAR-II/HEGIFTOM Project
Tracing elevated abundance of CH2Cl2 in the subarctic upper troposphere to the Asian Summer Monsoon
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
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
Significant influence of oxygenated volatile organic compounds on atmospheric chemistry analysis: A case study in a typical industrial city in China
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
Observation and modelling of atmospheric OH and HO2 radicals at a subtropical rural site and implications for secondary pollutants
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
Measurement report: Elevated atmospheric ammonia may promote particle pH and HONO formation – insights from the COVID-19 pandemic
Measurement report: Vertical and temporal variability in the near-surface ozone production rate and sensitivity in an urban area in the Pearl River Delta region, China
Elevated oxidized mercury in the free troposphere: analytical advances and application at a remote continental mountaintop site
Using observed urban NOx sinks to constrain VOC reactivity and the ozone and radical budget in the Seoul Metropolitan Area
Real-world emission characteristics of VOCs from typical cargo ships and their potential contributions to secondary organic aerosol and O3 under low-sulfur fuel policies
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.
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.
Can Ye, Pengfei Liu, Chaoyang Xue, Chenglong Zhang, Zhuobiao Ma, Chengtang Liu, Junfeng Liu, Keding Lu, Yujing Mu, and Yuanhang Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2025-795, https://doi.org/10.5194/egusphere-2025-795, 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 VOCs and NOx control is essential to reduce both H2O2 and ozone pollution.
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.
Yanjie Lu, Xinxin Feng, Yanli Feng, Minjun Jiang, Yu Peng, Tian Chen, and Yingjun Chen
EGUsphere, https://doi.org/10.5194/egusphere-2025-131, https://doi.org/10.5194/egusphere-2025-131, 2025
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The EFs of CCs from biomass burning (BB) is an order of magnitude higher than that from on-road sources. Fuel type determines the emission characteristics and composition of CCs. The formation of CCs from solid and liquid fuel sources is respectively controlled by combustion temperature and emission standards. In addition, biomass burning and agricultural machinery sources significantly contribute to the oxidizing capacity of regional atmospheres.
Shuwen Guo, Xuan Zheng, Xiao He, Lewei Zeng, Liqiang He, Xian Wu, Yifei Dai, Zihao Huang, Ting Chen, Shupei Xiao, Yan You, Sheng Xiang, Shaojun Zhang, Jingkun Jiang, and Ye Wu
Atmos. Chem. Phys., 25, 2695–2705, https://doi.org/10.5194/acp-25-2695-2025, https://doi.org/10.5194/acp-25-2695-2025, 2025
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We considered two potential influencing factors of heavy-duty diesel vehicle emissions that are rarely mentioned in the literature: cumulative mileage and ambient temperatures. The results suggest that prolonged use of heavy-duty diesel vehicles and low ambient temperatures leads to reduced engine combustion efficiency, which in turn increases tailpipe emissions significantly.
Junling Li, Chaofan Lian, Mingyuan Liu, Hao Zhang, Yongxin Yan, Yufei Song, Chun Chen, Jiaqi Wang, Haijie Zhang, Yanqin Ren, Yucong Guo, Weigang Wang, Yisheng Xu, Hong Li, Jian Gao, and Maofa Ge
Atmos. Chem. Phys., 25, 2551–2568, https://doi.org/10.5194/acp-25-2551-2025, https://doi.org/10.5194/acp-25-2551-2025, 2025
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As a key source of hydroxyl (OH) radical, nitrous acid (HONO) has attracted much attention for its important role in the atmospheric oxidant capacity (AOC) increase. In this study, we made a comparison of the ambient levels, variation patterns, sources, and formation pathway in the warm season on the basis of continuous intensive observations at an urban site of Beijing. This work highlights the importance of HONO for the AOC in the warm season.
Xiao-Bing Li, Bin Yuan, Yibo Huangfu, Suxia Yang, Xin Song, Jipeng Qi, Xianjun He, Sihang Wang, Yubin Chen, Qing Yang, Yongxin Song, Yuwen Peng, Guiqian Tang, Jian Gao, Dasa Gu, and Min Shao
Atmos. Chem. Phys., 25, 2459–2472, https://doi.org/10.5194/acp-25-2459-2025, https://doi.org/10.5194/acp-25-2459-2025, 2025
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Online vertical gradient measurements of volatile organic compounds (VOCs), ozone, and NOx were conducted based on a 325 m tall tower in urban Beijing. Vertical changes in the concentrations, compositions, key drivers, and environmental impacts of VOCs were analyzed in this study. We find that VOC species display differentiated vertical variation patterns and distinct roles in contributing to photochemical ozone formation with increasing height in the urban planetary boundary layer.
Shigeyuki Ishidoya, Satoshi Sugawara, and Atsushi Okazaki
Atmos. Chem. Phys., 25, 1965–1987, https://doi.org/10.5194/acp-25-1965-2025, https://doi.org/10.5194/acp-25-1965-2025, 2025
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The 18O/16O ratio of atmospheric oxygen, δatm(18O), is higher than that of ocean water due to isotopic effects during biospheric activities. This is known as the Dole–Morita effect, and its millennial-scale variations are recorded in ice cores. However, small variations of δatm(18O) in the present day have never been detected so far. This paper presents the first observations of diurnal, seasonal, and secular variations in δatm(18O) and applies them to evaluate oxygen, carbon, and water cycles.
Delaney B. Kilgour, Christopher M. Jernigan, Olga Garmash, Sneha Aggarwal, Shengqian Zhou, Claudia Mohr, Matt E. Salter, Joel A. Thornton, Jian Wang, Paul Zieger, and Timothy H. Bertram
Atmos. Chem. Phys., 25, 1931–1947, https://doi.org/10.5194/acp-25-1931-2025, https://doi.org/10.5194/acp-25-1931-2025, 2025
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We report simultaneous measurements of dimethyl sulfide (DMS) and hydroperoxymethyl thioformate (HPMTF) in the eastern North Atlantic. We use an observationally constrained box model to show that cloud loss is the dominant sink of HPMTF in this region over 6 weeks, resulting in large reductions in DMS-derived products that contribute to aerosol formation and growth. Our findings indicate that fast cloud processing of HPMTF must be included in global models to accurately capture the sulfur cycle.
Jiemeng Bao, Xin Zhang, Zhenhai Wu, Li Zhou, Jun Qian, Qinwen Tan, Fumo Yang, Junhui Chen, Yunfeng Li, Hefan Liu, Liqun Deng, and Hong Li
Atmos. Chem. Phys., 25, 1899–1916, https://doi.org/10.5194/acp-25-1899-2025, https://doi.org/10.5194/acp-25-1899-2025, 2025
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We studied carbonyl compounds' role in ozone pollution in the Chengdu Plain Urban Agglomeration, China. During heavy pollution in August 2019, we measured carbonyls at nine sites and analyzed their impact. Areas with higher carbonyl levels, like Chengdu, had worse ozone pollution. While their abundance matters, chemical reactions with other pollutants are the main drivers. Our findings show regional cooperation is vital to reducing ozone pollution effectively.
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.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-3736, https://doi.org/10.5194/egusphere-2024-3736, 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 will provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-3946, https://doi.org/10.5194/egusphere-2024-3946, 2025
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The study investigates transport within the Asian Summer Monsoon, focussing 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 analysed. The East Asian Summer Monsoon was identified as the main transport pathway, with only a small contribution to the stratosphere in the following days.
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.
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.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-3201, https://doi.org/10.5194/egusphere-2024-3201, 2024
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Oxygenated volatile organic compounds (OVOCs) are important ozone (O3) precursors. However, most of O3 formation analysis based on the box model (OBM) don't include OVOCs constraint To access the interference of OVOCs on O3 simulation, this study conducted field campaign and OBM analysis. The results indicates that no OVOCs constraint in the OBM can lead to overestimate of OVOCs, free radicals, and O3.
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.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-3210, https://doi.org/10.5194/egusphere-2024-3210, 2024
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We measured ambient OH and HO2 concentrations at a subtropical rural site and compared our observations with model results. During warm periods, the model overestimated the 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 HO2are formed and removed, which is important for accurate air quality and climate predictions.
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.
Xinyuan Zhang, Lingling Wang, Nan Wang, Shuangliang Ma, Shenbo Wang, Ruiqin Zhang, Dong Zhang, Mingkai Wang, and Hongyu Zhang
Atmos. Chem. Phys., 24, 9885–9898, https://doi.org/10.5194/acp-24-9885-2024, https://doi.org/10.5194/acp-24-9885-2024, 2024
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This study highlights the importance of the redox reaction of NO2 with SO2 based on actual atmospheric observations. The particle pH in future China is expected to rise steadily. Consequently, this reaction could become a significant source of HONO in China. Therefore, it is crucial to coordinate the control of SO2, NOx, and NH3 emissions to avoid a rapid increase in the particle pH.
Jun Zhou, Chunsheng Zhang, Aiming Liu, Bin Yuan, Yan Wang, Wenjie Wang, Jie-Ping Zhou, Yixin Hao, Xiao-Bing Li, Xianjun He, Xin Song, Yubin Chen, Suxia Yang, Shuchun Yang, Yanfeng Wu, Bin Jiang, Shan Huang, Junwen Liu, Yuwen Peng, Jipeng Qi, Minhui Deng, Bowen Zhong, Yibo Huangfu, and Min Shao
Atmos. Chem. Phys., 24, 9805–9826, https://doi.org/10.5194/acp-24-9805-2024, https://doi.org/10.5194/acp-24-9805-2024, 2024
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In-depth understanding of the near-ground vertical variability in photochemical ozone (O3) formation is crucial for mitigating O3 pollution. Utilizing a self-built vertical observation system, a direct net photochemical O3 production rate detection system, and an observation-based model, we diagnosed the vertical distributions and formation mechanism of net photochemical O3 production rates and sensitivity in the Pearl River Delta region, one of the most O3-polluted areas in China.
Eleanor J. Derry, Tyler R. Elgiar, Taylor Y. Wilmot, Nicholas W. Hoch, Noah S. Hirshorn, Peter Weiss-Penzias, Christopher F. Lee, John C. Lin, A. Gannet Hallar, Rainer Volkamer, Seth N. Lyman, and Lynne E. Gratz
Atmos. Chem. Phys., 24, 9615–9643, https://doi.org/10.5194/acp-24-9615-2024, https://doi.org/10.5194/acp-24-9615-2024, 2024
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Mercury (Hg) is a globally distributed neurotoxic pollutant. Atmospheric deposition is the main source of Hg in ecosystems. However, measurement biases hinder understanding of the origins and abundance of the more bioavailable oxidized form. We used an improved, calibrated measurement system to study air mass composition and transport of atmospheric Hg at a remote mountaintop site in the central US. Oxidized Hg originated upwind in the low to middle free troposphere under clean, dry conditions.
Benjamin A. Nault, Katherine R. Travis, James H. Crawford, Donald R. Blake, Pedro Campuzano-Jost, Ronald C. Cohen, Joshua P. DiGangi, Glenn S. Diskin, Samuel R. Hall, L. Gregory Huey, Jose L. Jimenez, Kyung-Eun Min, Young Ro Lee, Isobel J. Simpson, Kirk Ullmann, and Armin Wisthaler
Atmos. Chem. Phys., 24, 9573–9595, https://doi.org/10.5194/acp-24-9573-2024, https://doi.org/10.5194/acp-24-9573-2024, 2024
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Ozone (O3) is a pollutant formed from the reactions of gases emitted from various sources. In urban areas, the density of human activities can increase the O3 formation rate (P(O3)), thus impacting air quality and health. Observations collected over Seoul, South Korea, are used to constrain P(O3). A high local P(O3) was found; however, local P(O3) was partly reduced due to compounds typically ignored. These observations also provide constraints for unmeasured compounds that will impact P(O3).
Fan Zhang, Binyu Xiao, Zeyu Liu, Yan Zhang, Chongguo Tian, Rui Li, Can Wu, Yali Lei, Si Zhang, Xinyi Wan, Yubao Chen, Yong Han, Min Cui, Cheng Huang, Hongli Wang, Yingjun Chen, and Gehui Wang
Atmos. Chem. Phys., 24, 8999–9017, https://doi.org/10.5194/acp-24-8999-2024, https://doi.org/10.5194/acp-24-8999-2024, 2024
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Mandatory use of low-sulfur fuel due to global sulfur limit regulations means large uncertainties in volatile organic compound (VOC) emissions. On-board tests of VOCs from nine cargo ships in China were carried out. Results showed that switching from heavy-fuel oil to diesel increased emission factor VOCs by 48 % on average, enhancing O3 and the secondary organic aerosol formation potential. Thus, implementing a global ultra-low-sulfur oil policy needs to be optimized in the near future.
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Short summary
CO is one of the major air pollutants. Our study showed that the long-term CO levels at a background station in one of the most developed areas of China decreased significantly and verified that this downward trend was attributed to the decrease in anthropogenic emissions, which indicated that the adopted pollution control policies were effective. Also, this decrease has an implication for the atmospheric chemistry considering the negative correlation between CO levels and OH radical's lifetime.
CO is one of the major air pollutants. Our study showed that the long-term CO levels at a...
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