Articles | Volume 24, issue 6
https://doi.org/10.5194/acp-24-3541-2024
© Author(s) 2024. 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-24-3541-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 Mar 2024
Research article |
| 21 Mar 2024
| 21 Mar 2024
Mixing-layer-height-referenced ozone vertical distribution in the lower troposphere of Chinese megacities: stratification, classification, and meteorological and photochemical mechanisms
Zhiheng Liao
Institute of Urban Meteorology, China Meteorological Administration, Beijing, China
School of Atmospheric Sciences, Sun Yat-Sen University, Zhuhai, China
Department of Geography, Hong Kong Baptist University, Hong Kong SAR, China
Jinqiang Zhang
Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
Jiaren Sun
Key Laboratory of Urban Ecological Environmental Simulation and Protection of Ministry of Environmental Protection, South China Institute of Environmental Sciences, Ministry of Ecology and Environment of the PRC, Guangzhou, China
Jiannong Quan
Institute of Urban Meteorology, China Meteorological Administration, Beijing, China
Xingcan Jia
Institute of Urban Meteorology, China Meteorological Administration, Beijing, China
Yubing Pan
Institute of Urban Meteorology, China Meteorological Administration, Beijing, China
Shaojia Fan
CORRESPONDING AUTHOR
School of Atmospheric Sciences, Sun Yat-Sen University, Zhuhai, China
Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary, Key Laboratory of Tropical Atmosphere–Ocean System, Ministry of Education, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
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Light absorption and radiative forcing of black carbon (BC) is influenced by both BC itself and its interactions with other aerosol chemical compositions. In this study, we used the online coupled WRF-Chem model to examine how emission control measures during the Asian-Pacific Economic Cooperation (APEC) conference affect the mixing state and light absorption of BC and the associated implications for BC-PBL interactions.
Lian Zong, Yuanjian Yang, Meng Gao, Hong Wang, Peng Wang, Hongliang Zhang, Linlin Wang, Guicai Ning, Chao Liu, Yubin Li, and Zhiqiu Gao
Atmos. Chem. Phys., 21, 9105–9124, https://doi.org/10.5194/acp-21-9105-2021, https://doi.org/10.5194/acp-21-9105-2021, 2021
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In recent years, summer O3 pollution over eastern China has become more serious, and it is even the case that surface O3 and PM2.5 pollution can co-occur. However, the synoptic weather pattern (SWP) related to this compound pollution remains unclear. Regional PM2.5 and O3 compound pollution is characterized by various SWPs with different dominant factors. Our findings provide insights into the regional co-occurring high PM2.5 and O3 levels via the effects of certain meteorological factors.
Yan Zhang, Yu Zhao, Meng Gao, Xin Bo, and Chris P. Nielsen
Atmos. Chem. Phys., 21, 6411–6430, https://doi.org/10.5194/acp-21-6411-2021, https://doi.org/10.5194/acp-21-6411-2021, 2021
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We combined air quality and exposure response models to analyze the benefits for air quality and human health of China’s ultra-low emission policy in one of its most developed regions. Atmospheric observations and the air quality model were also used to demonstrate improvement of emission inventories incorporating online emission monitoring data. With implementation of the policy in both power and industrial sectors, the attributable deaths due to PM2.5 exposure are estimated to decrease 5.5 %.
Dandan Zhao, Jinyuan Xin, Chongshui Gong, Jiannong Quan, Yuesi Wang, Guiqian Tang, Yongxiang Ma, Lindong Dai, Xiaoyan Wu, Guangjing Liu, and Yongjing Ma
Atmos. Chem. Phys., 21, 5739–5753, https://doi.org/10.5194/acp-21-5739-2021, https://doi.org/10.5194/acp-21-5739-2021, 2021
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The influence of aerosol radiative forcing (ARF) on the boundary layer structure is nonlinear. The threshold of the modification effects of ARF on the boundary layer structure was determined for the first time, highlighting that once ARF exceeded a certain value, the boundary layer would quickly stabilize and aggravate air pollution. This could provide useful information for relevant atmospheric-environment improvement measures and policies.
Peter Sherman, Meng Gao, Shaojie Song, Alex T. Archibald, Nathan Luke Abraham, Jean-François Lamarque, Drew Shindell, Gregory Faluvegi, and Michael B. McElroy
Atmos. Chem. Phys., 21, 3593–3605, https://doi.org/10.5194/acp-21-3593-2021, https://doi.org/10.5194/acp-21-3593-2021, 2021
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The aims here are to assess the role of aerosols in India's monsoon precipitation and to determine the relative contributions from Chinese and Indian emissions using CMIP6 models. We find that increased sulfur emissions reduce precipitation, which is primarily dynamically driven due to spatial shifts in convection over the region. A significant increase in precipitation (up to ~ 20 %) is found only when both Indian and Chinese sulfate emissions are regulated.
Shaojie Song, Tao Ma, Yuzhong Zhang, Lu Shen, Pengfei Liu, Ke Li, Shixian Zhai, Haotian Zheng, Meng Gao, Jonathan M. Moch, Fengkui Duan, Kebin He, and Michael B. McElroy
Atmos. Chem. Phys., 21, 457–481, https://doi.org/10.5194/acp-21-457-2021, https://doi.org/10.5194/acp-21-457-2021, 2021
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We simulate the atmospheric chemical processes of an important sulfur-containing organic aerosol species, which is produced by the reaction between sulfur dioxide and formaldehyde. We can predict its distribution on a global scale. We find it is particularly rich in East Asia. This aerosol species is more abundant in the colder season partly because of weaker sunlight.
Yuli Zhang, Mengchu Tao, Jinqiang Zhang, Yi Liu, Hongbin Chen, Zhaonan Cai, and Paul Konopka
Atmos. Chem. Phys., 20, 13343–13354, https://doi.org/10.5194/acp-20-13343-2020, https://doi.org/10.5194/acp-20-13343-2020, 2020
Minqiang Zhou, Pucai Wang, Bavo Langerock, Corinne Vigouroux, Christian Hermans, Nicolas Kumps, Ting Wang, Yang Yang, Denghui Ji, Liang Ran, Jinqiang Zhang, Yuejian Xuan, Hongbin Chen, Françoise Posny, Valentin Duflot, Jean-Marc Metzger, and Martine De Mazière
Atmos. Meas. Tech., 13, 5379–5394, https://doi.org/10.5194/amt-13-5379-2020, https://doi.org/10.5194/amt-13-5379-2020, 2020
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We study O3 retrievals in the 3040 cm-1 spectral range from FTIR measurements at Xianghe China (39.75° N, 116.96° E; 50 m a.s.l.) between June 2018 and December 2019. It was found that the FTIR O3 (3040 cm-1) retrievals capture the seasonal and synoptic variations of O3 very well. The systematic and random uncertainties of FTIR O3 (3040 cm-1) total column are about 13.6 % and 1.4 %, respectively. The DOFS is 2.4±0.3 (1σ), with two individual pieces of information in surface–20 km and 20–40 km.
Junchen Guo, Shengzhen Zhou, Mingfu Cai, Jun Zhao, Wei Song, Weixiong Zhao, Weiwei Hu, Yele Sun, Yao He, Chengqiang Yang, Xuezhe Xu, Zhisheng Zhang, Peng Cheng, Qi Fan, Jian Hang, Shaojia Fan, Xinming Wang, and Xuemei Wang
Atmos. Chem. Phys., 20, 7595–7615, https://doi.org/10.5194/acp-20-7595-2020, https://doi.org/10.5194/acp-20-7595-2020, 2020
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We characterized non-refractory submicron particulate matter (PM1.0) during winter in Guangzhou, south China. Chemical composition and key sources of ambient PM1.0 are revealed, highlighting the significant role of SOA. The relationship with SOA and peroxy radicals indicated gas-phase oxidation contributed predominantly to SOA formation during non-pollution periods, while heterogeneous/multiphase reactions played more important roles in SOA formation during pollution periods.
Pablo E. Saide, Meng Gao, Zifeng Lu, Daniel L. Goldberg, David G. Streets, Jung-Hun Woo, Andreas Beyersdorf, Chelsea A. Corr, Kenneth L. Thornhill, Bruce Anderson, Johnathan W. Hair, Amin R. Nehrir, Glenn S. Diskin, Jose L. Jimenez, Benjamin A. Nault, Pedro Campuzano-Jost, Jack Dibb, Eric Heim, Kara D. Lamb, Joshua P. Schwarz, Anne E. Perring, Jhoon Kim, Myungje Choi, Brent Holben, Gabriele Pfister, Alma Hodzic, Gregory R. Carmichael, Louisa Emmons, and James H. Crawford
Atmos. Chem. Phys., 20, 6455–6478, https://doi.org/10.5194/acp-20-6455-2020, https://doi.org/10.5194/acp-20-6455-2020, 2020
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Air quality forecasts over the Korean Peninsula captured aerosol optical depth but largely overpredicted surface PM during a Chinese haze transport event. Model deficiency was related to the calculation of optical properties. In order to improve it, aerosol size representation needs to be refined in the calculations, and the representation of aerosol properties, such as size distribution, chemical composition, refractive index, hygroscopicity parameter, and density, needs to be improved.
Dandan Zhao, Guangjing Liu, Jinyuan Xin, Jiannong Quan, Yuesi Wang, Xin Wang, Lindong Dai, Wenkang Gao, Guiqian Tang, Bo Hu, Yongxiang Ma, Xiaoyan Wu, Lili Wang, Zirui Liu, and Fangkun Wu
Atmos. Chem. Phys., 20, 4575–4592, https://doi.org/10.5194/acp-20-4575-2020, https://doi.org/10.5194/acp-20-4575-2020, 2020
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Under strong atmospheric oxidization capacity, haze pollution in the summer in Beijing was the result of the synergistic effect of the physicochemical process in the atmospheric boundary layer (ABL). With the premise of an extremely stable ABL structure, the formation of secondary aerosols dominated by nitrate was quite intense, driving the outbreak of haze pollution.
Mengqi Liu, Xiangdong Zheng, Jinqiang Zhang, and Xiangao Xia
Atmos. Chem. Phys., 20, 4415–4426, https://doi.org/10.5194/acp-20-4415-2020, https://doi.org/10.5194/acp-20-4415-2020, 2020
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This study uses 1 min radiation and lidar measurements at three stations over the Tibetan Plateau (TP) to parametrize downward longwave radiation (DLR) during summer months. Clear-sky DLR can be estimated from the best parametrization with a RMSE of 3.8 W m-2 and R2 > 0.98. Additionally cloud base height under overcast conditions is shown to play an important role in cloudy DLR parametrization, which is considered in the locally calibrated parametrization over the TP for the first time.
Meng Gao, Jinhui Gao, Bin Zhu, Rajesh Kumar, Xiao Lu, Shaojie Song, Yuzhong Zhang, Beixi Jia, Peng Wang, Gufran Beig, Jianlin Hu, Qi Ying, Hongliang Zhang, Peter Sherman, and Michael B. McElroy
Atmos. Chem. Phys., 20, 4399–4414, https://doi.org/10.5194/acp-20-4399-2020, https://doi.org/10.5194/acp-20-4399-2020, 2020
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A regional fully coupled meteorology–chemistry model, Weather Research and Forecasting model with Chemistry (WRF-Chem), was employed to study the seasonality of ozone (O3) pollution and its sources in both China and India.
Dan Li, Bärbel Vogel, Rolf Müller, Jianchun Bian, Gebhard Günther, Felix Ploeger, Qian Li, Jinqiang Zhang, Zhixuan Bai, Holger Vömel, and Martin Riese
Atmos. Chem. Phys., 20, 4133–4152, https://doi.org/10.5194/acp-20-4133-2020, https://doi.org/10.5194/acp-20-4133-2020, 2020
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Low ozone and low water vapour signatures in the UTLS were investigated using balloon-borne measurements and trajectory calculations. The results show that deep convection in tropical cyclones over the western Pacific transports boundary air parcels with low ozone into the tropopause region. Subsequently, these air parcels are dehydrated when passing the lowest temperature region (< 190 K) during quasi-horizontal advection.
Zhining Tao, Mian Chin, Meng Gao, Tom Kucsera, Dongchul Kim, Huisheng Bian, Jun-ichi Kurokawa, Yuesi Wang, Zirui Liu, Gregory R. Carmichael, Zifa Wang, and Hajime Akimoto
Atmos. Chem. Phys., 20, 2319–2339, https://doi.org/10.5194/acp-20-2319-2020, https://doi.org/10.5194/acp-20-2319-2020, 2020
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One goal of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III is to identify strengths and weaknesses of current air quality models to provide insights into reducing uncertainties. This study identified that a 15 km grid would be the optimal horizontal resolution in terms of performance and resource usage to capture average and extreme air quality over East Asia and is thus suggested for use in future MICS-Asia modeling activities if the investigation domain remains the same.
Meng Gao, Zirui Liu, Bo Zheng, Dongsheng Ji, Peter Sherman, Shaojie Song, Jinyuan Xin, Cheng Liu, Yuesi Wang, Qiang Zhang, Jia Xing, Jingkun Jiang, Zifa Wang, Gregory R. Carmichael, and Michael B. McElroy
Atmos. Chem. Phys., 20, 1497–1505, https://doi.org/10.5194/acp-20-1497-2020, https://doi.org/10.5194/acp-20-1497-2020, 2020
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We quantified the relative influences of anthropogenic emissions and meteorological conditions on PM2.5 concentrations in Beijing over the winters of 2002–2016. Meteorological conditions over the study period would have led to an increase of haze in Beijing, but the strict emission control measures have suppressed the unfavorable influences of the recent climate.
Meng Gao, Zhiwei Han, Zhining Tao, Jiawei Li, Jeong-Eon Kang, Kan Huang, Xinyi Dong, Bingliang Zhuang, Shu Li, Baozhu Ge, Qizhong Wu, Hyo-Jung Lee, Cheol-Hee Kim, Joshua S. Fu, Tijian Wang, Mian Chin, Meng Li, Jung-Hun Woo, Qiang Zhang, Yafang Cheng, Zifa Wang, and Gregory R. Carmichael
Atmos. Chem. Phys., 20, 1147–1161, https://doi.org/10.5194/acp-20-1147-2020, https://doi.org/10.5194/acp-20-1147-2020, 2020
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Topic 3 of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III examines how online coupled air quality models perform in simulating high aerosol pollution in the North China Plain region during wintertime haze events and evaluates the importance of aerosol radiative feedbacks. This paper discusses the estimates of aerosol radiative forcing, aerosol feedbacks, and possible causes for the differences among the models.
Jingda Liu, Lili Wang, Mingge Li, Zhiheng Liao, Yang Sun, Tao Song, Wenkang Gao, Yonghong Wang, Yan Li, Dongsheng Ji, Bo Hu, Veli-Matti Kerminen, Yuesi Wang, and Markku Kulmala
Atmos. Chem. Phys., 19, 14477–14492, https://doi.org/10.5194/acp-19-14477-2019, https://doi.org/10.5194/acp-19-14477-2019, 2019
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We analyzed the surface ozone variation characteristics and quantified the impact of synoptic and local meteorological factors on northern China during the warm season based on multi-city, in situ ozone and meteorological data, as well as meteorological reanalysis. The results of quantitative exploration on synoptic and local meteorological factors influencing both interannual and day-to-day ozone variations will provide the scientific basis for evaluating emission reduction measures.
Junting Zhong, Xiaoye Zhang, Yaqiang Wang, Jizhi Wang, Xiaojing Shen, Hongsheng Zhang, Tijian Wang, Zhouqing Xie, Cheng Liu, Hengde Zhang, Tianliang Zhao, Junying Sun, Shaojia Fan, Zhiqiu Gao, Yubin Li, and Linlin Wang
Atmos. Chem. Phys., 19, 3287–3306, https://doi.org/10.5194/acp-19-3287-2019, https://doi.org/10.5194/acp-19-3287-2019, 2019
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In various haze regions in China, including the Guanzhong Plain, the middle and lower reaches of the Yangtze River, the Pearl River Delta, the Sichuan Basin, and the Northeast China Plain, heavy aerosol pollution episodes include inter-/trans-regional transport stages and cumulative stages (CSs). During CSs a two-way feedback mechanism exists between unfavorable meteorological conditions and cumulative aerosol pollution. This two-way feedback is further quantified and its magnitude is compared.
Daniel L. Goldberg, Pablo E. Saide, Lok N. Lamsal, Benjamin de Foy, Zifeng Lu, Jung-Hun Woo, Younha Kim, Jinseok Kim, Meng Gao, Gregory Carmichael, and David G. Streets
Atmos. Chem. Phys., 19, 1801–1818, https://doi.org/10.5194/acp-19-1801-2019, https://doi.org/10.5194/acp-19-1801-2019, 2019
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Using satellite data, we are able to estimate the emissions of NOx (NOx=NO+NO2), a toxic group of air pollutants, in the Seoul metropolitan area. We first develop an enhanced satellite product that better observes NO2 in urban regions. Using this new product, we derive NOx emissions to be twice as large as the emissions reported by the South Korean government. The implication is that the measures taken to reduce NOx emissions in South Korea have not been as effective as regulators have thought.
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).
Dan Li, Bärbel Vogel, Rolf Müller, Jianchun Bian, Gebhard Günther, Qian Li, Jinqiang Zhang, Zhixuan Bai, Holger Vömel, and Martin Riese
Atmos. Chem. Phys., 18, 17979–17994, https://doi.org/10.5194/acp-18-17979-2018, https://doi.org/10.5194/acp-18-17979-2018, 2018
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Balloon-borne measurements performed over Lhasa in August 2013 are investigated using CLaMS trajectory calculations. Here, we focus on high ozone mixing ratios in the free troposphere. Our findings demonstrate that both stratospheric intrusions and convective transport of air pollution play a major role in enhancing middle and upper tropospheric ozone.
Elizabeth M. Lennartson, Jun Wang, Juping Gu, Lorena Castro Garcia, Cui Ge, Meng Gao, Myungje Choi, Pablo E. Saide, Gregory R. Carmichael, Jhoon Kim, and Scott J. Janz
Atmos. Chem. Phys., 18, 15125–15144, https://doi.org/10.5194/acp-18-15125-2018, https://doi.org/10.5194/acp-18-15125-2018, 2018
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This paper is among the first to study the diurnal variations of AOD, PM2.5, and their relationships in South Korea. We show that the PM2.5–AOD relationship has strong diurnal variations, and, hence, using AOD data retrieved from geostationary satellite can improve the monitoring of surface PM2.5 air quality on a daily basis as well as constrain the diurnal variation of aerosol emission.
Shaojie Song, Meng Gao, Weiqi Xu, Jingyuan Shao, Guoliang Shi, Shuxiao Wang, Yuxuan Wang, Yele Sun, and Michael B. McElroy
Atmos. Chem. Phys., 18, 7423–7438, https://doi.org/10.5194/acp-18-7423-2018, https://doi.org/10.5194/acp-18-7423-2018, 2018
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Severe haze events occur frequently over northern China, especially in winter. Acidity plays a critical role in the formation of secondary PM2.5 and its toxicity. Using field measurements of gases and particles to critically evaluate two thermodynamic models routinely employed to determine particle acidity, we found that China's winter haze particles are generally within a moderately acidic range (pH 4–5) and not highly acidic (0) or neutral (7) as has been previously reported in the literature.
Zhiheng Liao, Jiaren Sun, Jialin Yao, Li Liu, Haowen Li, Jian Liu, Jielan Xie, Dui Wu, and Shaojia Fan
Atmos. Chem. Phys., 18, 6771–6783, https://doi.org/10.5194/acp-18-6771-2018, https://doi.org/10.5194/acp-18-6771-2018, 2018
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This paper investigates the modulation effect of ABL meteorology on Beijing’s surface air quality based on self-organizing maps. The self-organized ABL types correspond to significantly distinct pollutant loadings and diurnal evolution, particularly in winter. Anomalous stable ABL conditions are estimated to contribute 58.3 %, 46.4 % and 73.3 % of the elevated PM2.5 concentrations in January 2013, December 2015 and December 2016.
Meng Gao, Zhiwei Han, Zirui Liu, Meng Li, Jinyuan Xin, Zhining Tao, Jiawei Li, Jeong-Eon Kang, Kan Huang, Xinyi Dong, Bingliang Zhuang, Shu Li, Baozhu Ge, Qizhong Wu, Yafang Cheng, Yuesi Wang, Hyo-Jung Lee, Cheol-Hee Kim, Joshua S. Fu, Tijian Wang, Mian Chin, Jung-Hun Woo, Qiang Zhang, Zifa Wang, and Gregory R. Carmichael
Atmos. Chem. Phys., 18, 4859–4884, https://doi.org/10.5194/acp-18-4859-2018, https://doi.org/10.5194/acp-18-4859-2018, 2018
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Topic 3 of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III examines how online coupled air quality models perform in simulating high aerosol pollution in the North China Plain region during wintertime haze events and evaluates the importance of aerosol radiative and microphysical feedbacks. A comprehensive overview of the MICS-ASIA III Topic 3 study design is presented.
Xiao Lu, Lin Zhang, Xiong Liu, Meng Gao, Yuanhong Zhao, and Jingyuan Shao
Atmos. Chem. Phys., 18, 3101–3118, https://doi.org/10.5194/acp-18-3101-2018, https://doi.org/10.5194/acp-18-3101-2018, 2018
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Deteriorating tropospheric ozone pollution over India may not only affect local human health and vegetation but also perturb global ozone distribution. This study analyzes the processes controlling lower tropospheric ozone over India using OMI satellite observations (2006–2014) and model simulations (1990–2010). We show that the South Asian monsoon largely controls the seasonal cycle and interannual variability of Indian lower tropospheric ozone via changes in ozone production and transport.
Dan Li, Bärbel Vogel, Jianchun Bian, Rolf Müller, Laura L. Pan, Gebhard Günther, Zhixuan Bai, Qian Li, Jinqiang Zhang, Qiujun Fan, and Holger Vömel
Atmos. Chem. Phys., 17, 4657–4672, https://doi.org/10.5194/acp-17-4657-2017, https://doi.org/10.5194/acp-17-4657-2017, 2017
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High-resolution ozone and water vapour profiles over Lhasa, China, were measured in August 2013. The correlations between ozone and water vapour profiles show a strong variability in the upper troposphere. These relationships were investigated using CLaMS trajectory calculations. The model results demonstrate that three tropical cyclones (Jebi, Utor, and Trami), occurring over the western Pacific, had a strong impact on the vertical structure of ozone and water vapour profiles.
Meng Gao, Gregory R. Carmichael, Pablo E. Saide, Zifeng Lu, Man Yu, David G. Streets, and Zifa Wang
Atmos. Chem. Phys., 16, 11837–11851, https://doi.org/10.5194/acp-16-11837-2016, https://doi.org/10.5194/acp-16-11837-2016, 2016
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The WRF-Chem model was used to examine how the winter PM2.5 concentrations change in response to changes in emissions and meteorology in North China from 1960 to 2010. The discussions in this study indicate that dramatic changes in emissions are the main cause of increasing haze events in North China, and long-term trends in atmospheric circulations maybe another important cause. We also found aerosol feedbacks have been significantly enhanced from 1960 to 2010, due to higher aerosol loadings.
Guiqian Tang, Jinqiang Zhang, Xiaowan Zhu, Tao Song, Christoph Münkel, Bo Hu, Klaus Schäfer, Zirui Liu, Junke Zhang, Lili Wang, Jinyuan Xin, Peter Suppan, and Yuesi Wang
Atmos. Chem. Phys., 16, 2459–2475, https://doi.org/10.5194/acp-16-2459-2016, https://doi.org/10.5194/acp-16-2459-2016, 2016
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This is the first paper to validate and characterize mixing layer height and discuss its relationship with air pollution, using a ceilometer in Beijing. The novelty, originality, and importance of this paper are as follows: (1) the applicable conditions of the ceilometer; (2) the variations of mixing layer height; (3) thermal/dynamic structure inside mixing layers with different degrees of pollution; and (4) critical meteorological conditions for the formation of heavy air pollution.
M. Gao, G. R. Carmichael, Y. Wang, P. E. Saide, M. Yu, J. Xin, Z. Liu, and Z. Wang
Atmos. Chem. Phys., 16, 1673–1691, https://doi.org/10.5194/acp-16-1673-2016, https://doi.org/10.5194/acp-16-1673-2016, 2016
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The WRF-Chem model was applied to study the 2010 winter haze in North China. Air pollutants outside Beijing contributed about 64.5 % to the PM2.5 levels in Beijing during this haze event, and most of them are from south Hebei, Tianjin city, Shandong and Henan provinces. In addition, aerosol feedback has important impacts on surface temperature, Relative Humidity (RH) and wind speeds, and these meteorological variables affect aerosol distribution and formation in turn.
L. K. Xue, T. Wang, J. Gao, A. J. Ding, X. H. Zhou, D. R. Blake, X. F. Wang, S. M. Saunders, S. J. Fan, H. C. Zuo, Q. Z. Zhang, and W. X. Wang
Atmos. Chem. Phys., 14, 13175–13188, https://doi.org/10.5194/acp-14-13175-2014, https://doi.org/10.5194/acp-14-13175-2014, 2014
Z. J. Lin, Z. S. Zhang, L. Zhang, J. Tao, R. J. Zhang, J. J. Cao, S. J. Fan, and Y. H. Zhang
Atmos. Chem. Phys., 14, 7631–7644, https://doi.org/10.5194/acp-14-7631-2014, https://doi.org/10.5194/acp-14-7631-2014, 2014
L. K. Xue, T. Wang, J. Gao, A. J. Ding, X. H. Zhou, D. R. Blake, X. F. Wang, S. M. Saunders, S. J. Fan, H. C. Zuo, Q. Z. Zhang, and W. X. Wang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-27243-2013, https://doi.org/10.5194/acpd-13-27243-2013, 2013
Revised manuscript not accepted
H. Chen, Y. Zhu, J. Zhang, and Y. Xuan
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amtd-6-8107-2013, https://doi.org/10.5194/amtd-6-8107-2013, 2013
Revised manuscript not accepted
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
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Enhanced natural releases of mercury in response to the reduction in anthropogenic emissions during the COVID-19 lockdown by explainable machine learning
Temporal variability of tropospheric ozone and ozone profiles in the Korean Peninsula during the East Asian summer monsoon: insights from multiple measurements and reanalysis datasets
Retrieving CH4-emission rates from coal mine ventilation shafts using UAV-based AirCore observations and the genetic algorithm–interior point penalty function (GA-IPPF) model
Measurement report: Atmospheric mercury in a coastal city of Southeast China – inter-annual variations and influencing factors
Tropospheric and stratospheric ozone profiles during the 2019 TROpomi vaLIdation eXperiment (TROLIX-19)
Evaluation of correlated Pandora column NO2 and in situ surface NO2 measurements during GMAP campaign
Transport of substantial stratospheric ozone to the surface by a dying typhoon and shallow convection
Observational constraints on methane emissions from Polish coal mines using a ground-based remote sensing network
Continuous CH4 and δ13CH4 measurements in London demonstrate under-reported natural gas leakage
Long-term fluxes of carbonyl sulfide and their seasonality and interannual variability in a boreal forest
Declines and peaks in NO2 pollution during the multiple waves of the COVID-19 pandemic in the New York metropolitan area
Measurement report: Characterization of uncertainties in fluxes and fuel sulfur content from ship emissions in the Baltic Sea
Limitations of the radon tracer method (RTM) to estimate regional greenhouse gas (GHG) emissions – a case study for methane in Heidelberg
Positive and negative influences of typhoons on tropospheric ozone over southern China
Spatial and temporal variations of CO2 mole fractions observed at Beijing, Xianghe, and Xinglong in North China
The CO2 integral emission by the megacity of St Petersburg as quantified from ground-based FTIR measurements combined with dispersion modelling
Anthropogenic and natural controls on atmospheric δ13C-CO2 variations in the Yangtze River delta: insights from a carbon isotope modeling framework
Roger Curcoll, Alba Àgueda, Josep-Anton Morguí, Lídia Cañas, Sílvia Borràs, Arturo Vargas, and Claudia Grossi
Atmos. Chem. Phys., 25, 6299–6323, https://doi.org/10.5194/acp-25-6299-2025, https://doi.org/10.5194/acp-25-6299-2025, 2025
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In this work, the methane emissions from the rice crops of the Ebro Delta were estimated with the Radon Tracer Method, using back trajectories and radon and methane observations. Estimated fluxes show a strong seasonality with maximums in October, corresponding with the period of harvest and straw incorporation. The estimated annual methane emission was about 262.8 kg CH4 ha‑1. Results were compared with fluxes obtained with static chambers showing strong agreement between both methodologies.
Fan Lu, Kai Qin, Jason Blake Cohen, Qin He, Pravash Tiwari, Wei Hu, Chang Ye, Yanan Shan, Qing Xu, Shuo Wang, and Qiansi Tu
Atmos. Chem. Phys., 25, 5837–5856, https://doi.org/10.5194/acp-25-5837-2025, https://doi.org/10.5194/acp-25-5837-2025, 2025
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This work describes a field campaign and new fast emissions estimation approach to attribute methane from a large known and previously unknown coal mine in Shanxi, China. The emissions computed are shown to be larger than known oil and gas sources, indicating that methane from coal mines may play a larger role in the global methane budget. The results are found to be slightly larger than or similar to satellite observational campaigns over the same region.
Junyue Yang, Zhengning Xu, Zheng Xia, Xiangyu Pei, Yunye Yang, Botian Qiu, Shuang Zhao, Yuzhong Zhang, and Zhibin Wang
Atmos. Chem. Phys., 25, 4571–4585, https://doi.org/10.5194/acp-25-4571-2025, https://doi.org/10.5194/acp-25-4571-2025, 2025
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Mobile CH4 measurements were conducted at a wastewater treatment plant in Hangzhou in the summer and winter of 2023. A multi-source Gaussian plume model, combined with a genetic algorithm inversion framework, was used to locate major CH4 sources at the plant and quantify emissions. Results indicate that the summer CH4 emissions (603.33 ± 152.66 t a-1) were 2.8 times as high as inventory values, and winter values (418.95 ± 187.59 t a-1) were twice as high. The main sources were the screen and primary clarifier.
Bianca C. Baier, John B. Miller, Colm Sweeney, Scott Lehman, Chad Wolak, Joshua P. DiGangi, Yonghoon Choi, Kenneth Davis, Sha Feng, and Thomas Lauvaux
EGUsphere, https://doi.org/10.5194/egusphere-2025-821, https://doi.org/10.5194/egusphere-2025-821, 2025
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CO2 radiocarbon content (Δ14CO2) is a unique tracer helps to accurately quantify anthropogenic CO2 emitted into the atmosphere. Δ14CO2 measured in airborne flask samples is used to distinguish fossil versus biogenic CO2 sources. Mid-Atlantic U.S. CO2 variability is found to be driven by the biosphere. Errors in modeled fossil fuel CO2 are evaluated using Δ14CO2 airborne data as an avenue to improving future regional models of atmospheric CO2 transport.
Stuart K. Grange, Pascal Rubli, Andrea Fischer, Dominik Brunner, Christoph Hueglin, and Lukas Emmenegger
Atmos. Chem. Phys., 25, 2781–2806, https://doi.org/10.5194/acp-25-2781-2025, https://doi.org/10.5194/acp-25-2781-2025, 2025
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Carbon dioxide (CO2) is a very important atmospheric pollutant, and to better understand the gas's source and sink dynamics, a mid-cost sensor network hosting 26 sites was deployed in and around Zurich, Switzerland. The sensor measurement performance was quantified, and natural and anthropogenic CO2 emission sources were explored with a focus on what drives high CO2 levels. The observations will be used further by others to validate what is thought to be known about CO2 emissions in the region.
Androniki Maragkidou, Tiia Grönholm, Laura Rautiainen, Juha Nikmo, Jukka-Pekka Jalkanen, Timo Mäkelä, Timo Anttila, Lauri Laakso, and Jaakko Kukkonen
Atmos. Chem. Phys., 25, 2443–2457, https://doi.org/10.5194/acp-25-2443-2025, https://doi.org/10.5194/acp-25-2443-2025, 2025
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The Baltic Sea's designation as a sulfur emission control area in 2006, with subsequent regulations, significantly reduced sulfur emissions from shipping. Our study analysed air quality data from 2003 to 2020 on the island Utö and employed modelling, showing a continuous decrease in SO2 concentrations since 2003 and thus evidencing the effectiveness of such regulations in improving air quality. It also underscored the importance of long-term, high-resolution monitoring at remote marine sites.
Hossein Maazallahi, Foteini Stavropoulou, Samuel Jonson Sutanto, Michael Steiner, Dominik Brunner, Mariano Mertens, Patrick Jöckel, Antoon Visschedijk, Hugo Denier van der Gon, Stijn Dellaert, Nataly Velandia Salinas, Stefan Schwietzke, Daniel Zavala-Araiza, Sorin Ghemulet, Alexandru Pana, Magdalena Ardelean, Marius Corbu, Andreea Calcan, Stephen A. Conley, Mackenzie L. Smith, and Thomas Röckmann
Atmos. Chem. Phys., 25, 1497–1511, https://doi.org/10.5194/acp-25-1497-2025, https://doi.org/10.5194/acp-25-1497-2025, 2025
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This article presents insights from airborne in situ measurements collected during the ROmanian Methane Emissions from Oil and gas (ROMEO) campaign supported by two models. Results reveal Romania's oil and gas methane emissions were significantly under-reported to the United Nations Framework Convention on Climate Change (UNFCCC) in 2019. A large underestimation was also found in the Emissions Database for Global Atmospheric Research (EDGAR) v7.0 for the study domain in the same year.
Daniele Zannoni, Hans Christian Steen-Larsen, Harald Sodemann, Iris Thurnherr, Cyrille Flamant, Patrick Chazette, Julien Totems, Martin Werner, and Myriam Raybaut
EGUsphere, https://doi.org/10.5194/egusphere-2024-3394, https://doi.org/10.5194/egusphere-2024-3394, 2025
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High resolution airborne observations reveal that mixing between the free troposphere and surface evapotranspiration flux primarly modulates the water vapor isotopic composition in the lower troposphere. Water vapor isotopes structure variations occur on the scale of 100s of m, underlying the utility of stable isotopes for studying microscale atmospheric dynamics. This study also provides the basis for better validation of water vapor isotopes remote sensing retrievals with surface observations.
Sven Krautwurst, Christian Fruck, Sebastian Wolff, Jakob Borchardt, Oke Huhs, Konstantin Gerilowski, Michał Gałkowski, Christoph Kiemle, Mathieu Quatrevalet, Martin Wirth, Christian Mallaun, John P. Burrows, Christoph Gerbig, Andreas Fix, Hartmut Bösch, and Heinrich Bovensmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-3182, https://doi.org/10.5194/egusphere-2024-3182, 2024
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Anomalously high CH4 emissions from landfills in Madrid, Spain, have been observed by satellite measurements in recent years. Our investigations of these waste facilities using passive and active airborne remote sensing measurements confirm these high emission rates with values of up to 13 th-1 during the overflight and show excellent agreement between the two techniques. A large fraction of the emissions is attributed to active landfill sites.
Pharahilda M. Steur, Hubertus A. Scheeren, Gerbrand Koren, Getachew A. Adnew, Wouter Peters, and Harro A. J. Meijer
Atmos. Chem. Phys., 24, 11005–11027, https://doi.org/10.5194/acp-24-11005-2024, https://doi.org/10.5194/acp-24-11005-2024, 2024
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We present records of the triple oxygen isotope signature (Δ(17O)) of atmospheric CO2 obtained with laser absorption spectroscopy from two mid-latitude stations. Significant interannual variability is observed in both records. A model sensitivity study suggests that stratosphere–troposphere exchange, which carries high-Δ(17O) CO2 from the stratosphere into the troposphere, causes most of the variability. This makes Δ(17O) a potential tracer for stratospheric intrusions into the troposphere.
Ziru Lan, Xiaoyi Zhang, Weili Lin, Xiaobin Xu, Zhiqiang Ma, Jun Jin, Lingyan Wu, and Yangmei Zhang
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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Our study examined the long-term trends of atmospheric ammonia in urban Beijing from 2009 to 2020. We found that the trends did not match satellite data or emission estimates, revealing complexities in ammonia sources. While seasonal variations in ammonia were temperature-dependent, daily variations were correlated with water vapor. We also found an increasing contribution of ammonia reduction, emphasizing its importance in mitigating the effects of fine particulate matter in Beijing.
Luiz A. T. Machado, Jürgen Kesselmeier, Santiago Botía, Hella van Asperen, Meinrat O. Andreae, Alessandro C. de Araújo, Paulo Artaxo, Achim Edtbauer, Rosaria R. Ferreira, Marco A. Franco, Hartwig Harder, Sam P. Jones, Cléo Q. Dias-Júnior, Guido G. Haytzmann, Carlos A. Quesada, Shujiro Komiya, Jost Lavric, Jos Lelieveld, Ingeborg Levin, Anke Nölscher, Eva Pfannerstill, Mira L. Pöhlker, Ulrich Pöschl, Akima Ringsdorf, Luciana Rizzo, Ana M. Yáñez-Serrano, Susan Trumbore, Wanda I. D. Valenti, Jordi Vila-Guerau de Arellano, David Walter, Jonathan Williams, Stefan Wolff, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 8893–8910, https://doi.org/10.5194/acp-24-8893-2024, https://doi.org/10.5194/acp-24-8893-2024, 2024
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Composite analysis of gas concentration before and after rainfall, during the day and night, gives insight into the complex relationship between trace gas variability and precipitation. The analysis helps us to understand the sources and sinks of trace gases within a forest ecosystem. It elucidates processes that are not discernible under undisturbed conditions and contributes to a deeper understanding of the trace gas life cycle and its intricate interactions with cloud dynamics in the Amazon.
Fabian Maier, Ingeborg Levin, Sébastien Conil, Maksym Gachkivskyi, Hugo Denier van der Gon, and Samuel Hammer
Atmos. Chem. Phys., 24, 8205–8223, https://doi.org/10.5194/acp-24-8205-2024, https://doi.org/10.5194/acp-24-8205-2024, 2024
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We assess the uncertainty in continuous fossil fuel carbon dioxide (ffCO2) estimates derived from carbon monoxide (CO) observations and radiocarbon (14CO2) flask measurements from an urban and a rural site. This study provides the basis for using continuous CO-based ffCO2 observations in atmospheric transport inversion frameworks to derive ffCO2 emission estimates. We also compare the flask-based CO / ffCO2 ratios with modeled ratios to validate an emission inventory for central Europe.
Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Ninong Komala, Habib Khirzin Al-Ghazali, Dian Yudha Risdianto, Ambun Dindang, Ahmad Fairudz bin Jamaluddin, Mohan Kumar Sammathuria, Norazura Binti Zakaria, Bryan J. Johnson, and Patrick D. Cullis
Atmos. Chem. Phys., 24, 5221–5234, https://doi.org/10.5194/acp-24-5221-2024, https://doi.org/10.5194/acp-24-5221-2024, 2024
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SHADOZ balloon-borne ozone measurements over equatorial Southeast Asia from 1998–2022 reveal that ozone increases during the early months of the year are linked to reduced convective storm activity, which typically redistributes and cleans the atmosphere of ozone. These findings challenge models to replicate the trends produced by the SHADOZ and meteorological observations and emphasize the importance of studying monthly or seasonal instead of annual changes for understanding ozone trends.
Katrin Müller, Peter von der Gathen, and Markus Rex
Atmos. Chem. Phys., 24, 4693–4716, https://doi.org/10.5194/acp-24-4693-2024, https://doi.org/10.5194/acp-24-4693-2024, 2024
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The transport history of tropospheric air masses above the tropical western Pacific is studied by local ozone and relative humidity profile measurements from Palau. A prominent anti-correlation between both tracers separates air masses of different origin and genesis. Back trajectories confirm a local convective origin of the year-round humid ozone-poor background. Anomalously dry ozone-rich air is generated in tropical Asia by pollution and dehydrated during transport via radiative cooling.
Antje Hoheisel and Martina Schmidt
Atmos. Chem. Phys., 24, 2951–2969, https://doi.org/10.5194/acp-24-2951-2024, https://doi.org/10.5194/acp-24-2951-2024, 2024
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In Heidelberg, Germany, methane and its stable carbon isotope composition have been measured continuously with a cavity ring-down spectroscopy (CRDS) analyser since April 2014. These 6-year time series are analysed with the Keeling plot method for the isotopic composition of the sources, as well as seasonal variations and trends in methane emissions. The source contributions derived from atmospheric measurements were used to evaluate global and regional emission inventories of methane.
Tingting Hu, Yu Lin, Run Liu, Yuepeng Xu, Shanshan Ouyang, Boguang Wang, Yuanhang Zhang, and Shaw Chen Liu
Atmos. Chem. Phys., 24, 1607–1626, https://doi.org/10.5194/acp-24-1607-2024, https://doi.org/10.5194/acp-24-1607-2024, 2024
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We hypothesize that the cause of the worsening O3 trends in the Beijing–Tianjin–Hebei region, the Yangtze River Delta, and Pearl River Delta from 2015 to 2020 is attributable to the increased occurrence of meteorological conditions of high solar radiation and a positive temperature anomaly under the influence of West Pacific subtropical high, tropical cyclones, and mid–high-latitude wave activities.
Joseph Seitz, Shiyuan Zhong, Joseph J. Charney, Warren E. Heilman, Kenneth L. Clark, Xindi Bian, Nicholas S. Skowronski, Michael R. Gallagher, Matthew Patterson, Jason Cole, Michael T. Kiefer, Rory Hadden, and Eric Mueller
Atmos. Chem. Phys., 24, 1119–1142, https://doi.org/10.5194/acp-24-1119-2024, https://doi.org/10.5194/acp-24-1119-2024, 2024
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Atmospheric turbulence affects wildland fire behaviors and heat and smoke transfer. Turbulence data collected during an experimental fire on a 10 m x 10 m densely instrumented burn plot are analyzed, and the results reveal substantial heterogeneity in fire-induced turbulence characteristics across the small plot, which highlights the necessity for coupled atmosphere–fire behavior models to have 1–2 m grid spacing so that adequate simulations of fire behavior and smoke transfer can be achieved.
Davide Putero, Paolo Cristofanelli, Kai-Lan Chang, Gaëlle Dufour, Gregory Beachley, Cédric Couret, Peter Effertz, Daniel A. Jaffe, Dagmar Kubistin, Jason Lynch, Irina Petropavlovskikh, Melissa Puchalski, Timothy Sharac, Barkley C. Sive, Martin Steinbacher, Carlos Torres, and Owen R. Cooper
Atmos. Chem. Phys., 23, 15693–15709, https://doi.org/10.5194/acp-23-15693-2023, https://doi.org/10.5194/acp-23-15693-2023, 2023
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We investigated the impact of societal restriction measures during the COVID-19 pandemic on surface ozone at 41 high-elevation sites worldwide. Negative ozone anomalies were observed for spring and summer 2020 for all of the regions considered. In 2021, negative anomalies continued for Europe and partially for the eastern US, while western US sites showed positive anomalies due to wildfires. IASI satellite data and the Carbon Monitor supported emission reductions as a cause of the anomalies.
Xuanyi Zhang, Mark Gordon, Paul A. Makar, Timothy Jiang, Jonathan Davies, and David Tarasick
Atmos. Chem. Phys., 23, 13647–13664, https://doi.org/10.5194/acp-23-13647-2023, https://doi.org/10.5194/acp-23-13647-2023, 2023
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Measurements of ozone in the atmosphere were made in a forest downwind of oil sands mining and production facilities in northern Alberta. These measurements show that the emissions of other pollutants from oil sands production and processing reduce the amount of ozone in the forest. By using an atmospheric model combined with measurements, we find that the rate at which ozone is absorbed by the forest is lower than typical rates from similar measurements in other forests.
Thomas Trickl, Cédric Couret, Ludwig Ries, and Hannes Vogelmann
Atmos. Chem. Phys., 23, 8403–8427, https://doi.org/10.5194/acp-23-8403-2023, https://doi.org/10.5194/acp-23-8403-2023, 2023
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Downward atmospheric transport from the stratosphere (STT) is the most important natural source of tropospheric ozone. We analyse the stratospheric influence on the long-term series of ozone and carbon monoxide measured on the Zugspitze in the Bavarian Alps (2962 m a.s.l.). Since the 1970s, there has been a pronounced ozone rise that has been ascribed to an increase in STT. We determine the stratospheric influence from the observational data alone (humidity and 7Be).
Mark Gordon, Dane Blanchard, Timothy Jiang, Paul A. Makar, Ralf M. Staebler, Julian Aherne, Cris Mihele, and Xuanyi Zhang
Atmos. Chem. Phys., 23, 7241–7255, https://doi.org/10.5194/acp-23-7241-2023, https://doi.org/10.5194/acp-23-7241-2023, 2023
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Measurements of the gas sulfur dioxide (SO2) were made in a forest downwind of oil sands mining and production facilities in northern Alberta. These measurements tell us the rate at which SO2 is absorbed by the forest. The measured rate is much higher than what is currently used by air quality models, which is supported by a previous study in this region. This suggests that SO2 may have a much shorter lifetime in the atmosphere at this location than currently predicted by models.
Andreas Forstmaier, Jia Chen, Florian Dietrich, Juan Bettinelli, Hossein Maazallahi, Carsten Schneider, Dominik Winkler, Xinxu Zhao, Taylor Jones, Carina van der Veen, Norman Wildmann, Moritz Makowski, Aydin Uzun, Friedrich Klappenbach, Hugo Denier van der Gon, Stefan Schwietzke, and Thomas Röckmann
Atmos. Chem. Phys., 23, 6897–6922, https://doi.org/10.5194/acp-23-6897-2023, https://doi.org/10.5194/acp-23-6897-2023, 2023
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Large cities emit greenhouse gases which contribute to global warming. In this study, we measured the release of one important green house gas, methane, in Hamburg. Multiple sources that contribute to methane emissions were located and quantified. Methane sources were found to be mainly caused by human activity (e.g., by release from oil and gas refineries). Moreover, potential natural sources have been located, such as the Elbe River and lakes.
Truls Andersen, Zhao Zhao, Marcel de Vries, Jaroslaw Necki, Justyna Swolkien, Malika Menoud, Thomas Röckmann, Anke Roiger, Andreas Fix, Wouter Peters, and Huilin Chen
Atmos. Chem. Phys., 23, 5191–5216, https://doi.org/10.5194/acp-23-5191-2023, https://doi.org/10.5194/acp-23-5191-2023, 2023
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The Upper Silesian Coal Basin, Poland, is one of the hot spots of methane emissions in Europe. Using an uncrewed aerial vehicle (UAV), we performed atmospheric measurements of methane concentrations downwind of five ventilation shafts in this region and determined the emission rates from the individual shafts. We found a strong correlation between quantified shaft-averaged emission rates and hourly inventory data, which also allows us to estimate the methane emissions from the entire region.
Saginela Ravindra Babu, Chang-Feng Ou-Yang, Stephen M. Griffith, Shantanu Kumar Pani, Steven Soon-Kai Kong, and Neng-Huei Lin
Atmos. Chem. Phys., 23, 4727–4740, https://doi.org/10.5194/acp-23-4727-2023, https://doi.org/10.5194/acp-23-4727-2023, 2023
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In October 2006 and 2015, extensive fire episodes occurred in Indonesia, releasing an enormous amount of CO emissions. By combining in situ and satellite CO measurements and reanalysis products, we reported plausible transport pathways of CO from Indonesia to the Lulin Atmospheric Background Station (LABS; 23.47° N, 120.87° E; 2862 m a.s.l.) in Taiwan. We identified (i) horizontal transport in the free troposphere and (ii) vertical transport through the Hadley circulation.
Cheng Hu, Junqing Zhang, Bing Qi, Rongguang Du, Xiaofei Xu, Haoyu Xiong, Huili Liu, Xinyue Ai, Yiyi Peng, and Wei Xiao
Atmos. Chem. Phys., 23, 4501–4520, https://doi.org/10.5194/acp-23-4501-2023, https://doi.org/10.5194/acp-23-4501-2023, 2023
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We build the first city-scale tower-based atmospheric CH4 concentration observation network in China. The a priori total annual anthropogenic CH4 emissions and emissions from waste treatment were overestimated by 36.0 % and 47.1 %, respectively, in Hangzhou. Global warming will largely enhance the CH4 emission factor of waste treatment, which will increase by 17.6 %, 9.6 %, 5.6 % and 4.0 % for Representative Concentration Pathway (RCP) 8.5, RCP6.0, RCP4.5 and RCP2.6, respectively, by 2100.
Clément Narbaud, Jean-Daniel Paris, Sophie Wittig, Antoine Berchet, Marielle Saunois, Philippe Nédélec, Boris D. Belan, Mikhail Y. Arshinov, Sergei B. Belan, Denis Davydov, Alexander Fofonov, and Artem Kozlov
Atmos. Chem. Phys., 23, 2293–2314, https://doi.org/10.5194/acp-23-2293-2023, https://doi.org/10.5194/acp-23-2293-2023, 2023
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We measured CH4 and CO2 from aircraft over the Russian Arctic. Analyzing our data with the Lagrangian model FLEXPART, we find a sharp east–west gradient in atmospheric composition. Western Siberia is influenced by strong wetland CH4 emissions, deep CO2 gradient from biospheric uptake, and long-range transport from Europe and North America. Eastern flights document less variability. Over the Arctic Ocean, we find a small influence from marine CH4 emissions compatible with reasonable inventories.
Flora Kluge, Tilman Hüneke, Christophe Lerot, Simon Rosanka, Meike K. Rotermund, Domenico Taraborrelli, Benjamin Weyland, and Klaus Pfeilsticker
Atmos. Chem. Phys., 23, 1369–1401, https://doi.org/10.5194/acp-23-1369-2023, https://doi.org/10.5194/acp-23-1369-2023, 2023
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Using airborne glyoxal concentration and vertical column density measurements, vertical profiles are inferred for eight global regions in aged biomass burning plumes and the tropical marine boundary layer. Using TROPOMI observations, an analysis of space- and airborne measurements is performed. A comparison to EMAC simulations shows a general glyoxal underprediction, which points to various missing sources and precursors from anthropogenic activities, biomass burning, and the sea surface.
Alkuin M. Koenig, Olivier Magand, Bert Verreyken, Jerome Brioude, Crist Amelynck, Niels Schoon, Aurélie Colomb, Beatriz Ferreira Araujo, Michel Ramonet, Mahesh K. Sha, Jean-Pierre Cammas, Jeroen E. Sonke, and Aurélien Dommergue
Atmos. Chem. Phys., 23, 1309–1328, https://doi.org/10.5194/acp-23-1309-2023, https://doi.org/10.5194/acp-23-1309-2023, 2023
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The global distribution of mercury, a potent neurotoxin, depends on atmospheric transport, chemistry, and interactions between the Earth’s surface and the air. Our understanding of these processes is still hampered by insufficient observations. Here, we present new data from a mountain observatory in the Southern Hemisphere. We give insights into mercury concentrations in air masses coming from aloft, and we show that tropical mountain vegetation may be a daytime source of mercury to the air.
Kim A. P. Faassen, Linh N. T. Nguyen, Eadin R. Broekema, Bert A. M. Kers, Ivan Mammarella, Timo Vesala, Penelope A. Pickers, Andrew C. Manning, Jordi Vilà-Guerau de Arellano, Harro A. J. Meijer, Wouter Peters, and Ingrid T. Luijkx
Atmos. Chem. Phys., 23, 851–876, https://doi.org/10.5194/acp-23-851-2023, https://doi.org/10.5194/acp-23-851-2023, 2023
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The exchange ratio (ER) between atmospheric O2 and CO2 provides a useful tracer for separately estimating photosynthesis and respiration processes in the forest carbon balance. This is highly relevant to better understand the expected biosphere sink, which determines future atmospheric CO2 levels. We therefore measured O2, CO2, and their ER above a boreal forest in Finland and investigated their diurnal behaviour for a representative day, and we show the most suitable way to determine the ER.
Marc Prange, Stefan A. Buehler, and Manfred Brath
Atmos. Chem. Phys., 23, 725–741, https://doi.org/10.5194/acp-23-725-2023, https://doi.org/10.5194/acp-23-725-2023, 2023
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We investigate the representation of elevated moist layers (EMLs) in two satellite retrieval products and ERA5 reanalysis. EMLs occur in the vicinity of tropical convective storms and are thought to have an impact on their evolution through radiative heating. We provide a first dedicated assessment of EMLs in long-term data products in terms of moist layer strength, vertical thickness and altitude by comparing to collocated radiosondes over the western Pacific, a region where EMLs often occur.
Yongkang Wu, Weihua Chen, Yingchang You, Qianqian Xie, Shiguo Jia, and Xuemei Wang
Atmos. Chem. Phys., 23, 453–469, https://doi.org/10.5194/acp-23-453-2023, https://doi.org/10.5194/acp-23-453-2023, 2023
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Relying on observed and simulated data, we determine the spatiotemporal characteristics of nocturnal O3 increase (NOI) events in the Pearl River Delta region during 2006–2019. Low-level jets and convective storms are the main meteorological processes causing NOI. Daytime O3 is another essential influencing factor. More importantly, a more prominent role of meteorological processes in NOI has been demonstrated. Our study highlights the important role of meteorology in nocturnal O3 pollution.
Justyna Swolkień, Andreas Fix, and Michał Gałkowski
Atmos. Chem. Phys., 22, 16031–16052, https://doi.org/10.5194/acp-22-16031-2022, https://doi.org/10.5194/acp-22-16031-2022, 2022
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Determination of emissions from coal mines on a local scale requires instantaneous data. We analysed temporal emission data for ventilation shafts and factors influencing their variability. They were saturation of the seams with methane, the permeability of the rock mass, and coal output. The data for the verification should reflect the actual values of emissions from point sources. It is recommended to achieve this by using a standardised emission measurement system for all coal mines.
Xiaofei Qin, Shengqian Zhou, Hao Li, Guochen Wang, Cheng Chen, Chengfeng Liu, Xiaohao Wang, Juntao Huo, Yanfen Lin, Jia Chen, Qingyan Fu, Yusen Duan, Kan Huang, and Congrui Deng
Atmos. Chem. Phys., 22, 15851–15865, https://doi.org/10.5194/acp-22-15851-2022, https://doi.org/10.5194/acp-22-15851-2022, 2022
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Using artificial neural network modeling and an explainable analysis approach, natural surface emissions (NSEs) were identified as a main driver of gaseous elemental mercury (GEM) variations during the COVID-19 lockdown. A sharp drop in GEM concentrations due to a significant reduction in anthropogenic emissions may disrupt the surface–air exchange balance of Hg, leading to increases in NSEs. This implies that NSEs may pose challenges to the future control of Hg pollution.
Juseon Bak, Eun-Ji Song, Hyo-Jung Lee, Xiong Liu, Ja-Ho Koo, Joowan Kim, Wonbae Jeon, Jae-Hwan Kim, and Cheol-Hee Kim
Atmos. Chem. Phys., 22, 14177–14187, https://doi.org/10.5194/acp-22-14177-2022, https://doi.org/10.5194/acp-22-14177-2022, 2022
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Our study investigates the temporal variations of ozone profiles at Pohang in the Korean Peninsula from multiple ozone products. We discuss the quantitative relationships between daily surface measurements and key meteorological variables, different seasonality of ozone between the troposphere and stratosphere, and interannual changes in the lower tropospheric ozone, linked by the weather pattern driven by the East Asian summer monsoon.
Tianqi Shi, Zeyu Han, Ge Han, Xin Ma, Huilin Chen, Truls Andersen, Huiqin Mao, Cuihong Chen, Haowei Zhang, and Wei Gong
Atmos. Chem. Phys., 22, 13881–13896, https://doi.org/10.5194/acp-22-13881-2022, https://doi.org/10.5194/acp-22-13881-2022, 2022
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CH4 works as the second-most important greenhouse gas, its reported emission inventories being far less than CO2. In this study, we developed a self-adjusted model to estimate the CH4 emission rate from strong point sources by the UAV-based AirCore system. This model would reduce the uncertainty in CH4 emission rate quantification accrued by errors in measurements of wind and concentration. Actual measurements on Pniówek coal demonstrate the high accuracy and stability of our developed model.
Jiayan Shi, Yuping Chen, Lingling Xu, Youwei Hong, Mengren Li, Xiaolong Fan, Liqian Yin, Yanting Chen, Chen Yang, Gaojie Chen, Taotao Liu, Xiaoting Ji, and Jinsheng Chen
Atmos. Chem. Phys., 22, 11187–11202, https://doi.org/10.5194/acp-22-11187-2022, https://doi.org/10.5194/acp-22-11187-2022, 2022
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Gaseous elemental mercury (GEM) was observed in Southeast China over the period 2012–2020. The observed GEM concentrations showed no distinct inter-annual variation trends. The interpretation rate of transportation and meteorology on GEM variations displayed an increasing trend. In contrast, anthropogenic emissions have shown a decreasing interpretation rate since 2012, indicating the effectiveness of emission mitigation measures in reducing GEM concentrations in the study region.
John T. Sullivan, Arnoud Apituley, Nora Mettig, Karin Kreher, K. Emma Knowland, Marc Allaart, Ankie Piters, Michel Van Roozendael, Pepijn Veefkind, Jerry R. Ziemke, Natalya Kramarova, Mark Weber, Alexei Rozanov, Laurence Twigg, Grant Sumnicht, and Thomas J. McGee
Atmos. Chem. Phys., 22, 11137–11153, https://doi.org/10.5194/acp-22-11137-2022, https://doi.org/10.5194/acp-22-11137-2022, 2022
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A TROPOspheric Monitoring Instrument (TROPOMI) validation campaign (TROLIX-19) was held in the Netherlands in September 2019. The research presented here focuses on using ozone lidars from NASA’s Goddard Space Flight Center to better evaluate the characterization of ozone throughout TROLIX-19 as compared to balloon-borne, space-borne and ground-based passive measurements, as well as a global coupled chemistry meteorology model.
Lim-Seok Chang, Donghee Kim, Hyunkee Hong, Deok-Rae Kim, Jeong-Ah Yu, Kwangyul Lee, Hanlim Lee, Daewon Kim, Jinkyu Hong, Hyun-Young Jo, and Cheol-Hee Kim
Atmos. Chem. Phys., 22, 10703–10720, https://doi.org/10.5194/acp-22-10703-2022, https://doi.org/10.5194/acp-22-10703-2022, 2022
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Our study explored the synergy of combined column and surface measurements during GMAP (GEMS Map of Air Pollution) campaign. It has several points to note for vertical distribution analysis. Particularly under prevailing local wind meteorological conditions, Pandora-based vertical structures sometimes showed negative correlations between column and surface measurements. Vertical analysis should be done carefully in some local meteorological conditions when employing either surface or columns.
Zhixiong Chen, Jane Liu, Xiushu Qie, Xugeng Cheng, Yukun Shen, Mengmiao Yang, Rubin Jiang, and Xiangke Liu
Atmos. Chem. Phys., 22, 8221–8240, https://doi.org/10.5194/acp-22-8221-2022, https://doi.org/10.5194/acp-22-8221-2022, 2022
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A vigorous surface ozone surge event of stratospheric origin occurred in the North China Plain at night. Surface ozone concentrations were 40–50 ppbv higher than the corresponding monthly mean, whereas surface carbon monoxide concentrations declined abruptly, which confirmed the direct stratospheric intrusions to the surface. We further addressed the notion that a combined effect of the dying typhoon and mesoscale convective systems was responsible for this vigorous ozone surge.
Andreas Luther, Julian Kostinek, Ralph Kleinschek, Sara Defratyka, Mila Stanisavljević, Andreas Forstmaier, Alexandru Dandocsi, Leon Scheidweiler, Darko Dubravica, Norman Wildmann, Frank Hase, Matthias M. Frey, Jia Chen, Florian Dietrich, Jarosław Nȩcki, Justyna Swolkień, Christoph Knote, Sanam N. Vardag, Anke Roiger, and André Butz
Atmos. Chem. Phys., 22, 5859–5876, https://doi.org/10.5194/acp-22-5859-2022, https://doi.org/10.5194/acp-22-5859-2022, 2022
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Coal mining is an extensive source of anthropogenic methane emissions. In order to reduce and mitigate methane emissions, it is important to know how much and where the methane is emitted. We estimated coal mining methane emissions in Poland based on atmospheric methane measurements and particle dispersion modeling. In general, our emission estimates suggest higher emissions than expected by previous annual emission reports.
Eric Saboya, Giulia Zazzeri, Heather Graven, Alistair J. Manning, and Sylvia Englund Michel
Atmos. Chem. Phys., 22, 3595–3613, https://doi.org/10.5194/acp-22-3595-2022, https://doi.org/10.5194/acp-22-3595-2022, 2022
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Continuous measurements of atmospheric methane concentrations and its carbon-13 isotope have been made in central London since early 2018. These measurements were used to evaluate methane emissions reported in global and UK-specific emission inventories for the London area. Compared to atmospheric methane measurements from March 2018 to October 2020, both inventories are under-reporting natural gas leakage for the London area.
Timo Vesala, Kukka-Maaria Kohonen, Linda M. J. Kooijmans, Arnaud P. Praplan, Lenka Foltýnová, Pasi Kolari, Markku Kulmala, Jaana Bäck, David Nelson, Dan Yakir, Mark Zahniser, and Ivan Mammarella
Atmos. Chem. Phys., 22, 2569–2584, https://doi.org/10.5194/acp-22-2569-2022, https://doi.org/10.5194/acp-22-2569-2022, 2022
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Carbonyl sulfide (COS) provides new insights into carbon cycle research. We present an easy-to-use flux parameterization and the longest existing time series of forest–atmosphere COS exchange measurements, which allow us to study both seasonal and interannual variability. We observed only uptake of COS by the forest on an annual basis, with 37 % variability between years. Upscaling the boreal COS uptake using a biosphere model indicates a significant missing COS sink at high latitudes.
Maria Tzortziou, Charlotte F. Kwong, Daniel Goldberg, Luke Schiferl, Róisín Commane, Nader Abuhassan, James J. Szykman, and Lukas C. Valin
Atmos. Chem. Phys., 22, 2399–2417, https://doi.org/10.5194/acp-22-2399-2022, https://doi.org/10.5194/acp-22-2399-2022, 2022
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The COVID-19 pandemic created an extreme natural experiment in which sudden changes in human behavior significantly impacted urban air quality. Using a combination of model, satellite, and ground-based data, we examine the impact of multiple waves and phases of the pandemic on atmospheric nitrogen pollution in the New York metropolitan area, and address the role of weather as a key driver of high pollution episodes observed even during – and despite – the stringent early lockdowns.
Jari Walden, Liisa Pirjola, Tuomas Laurila, Juha Hatakka, Heidi Pettersson, Tuomas Walden, Jukka-Pekka Jalkanen, Harri Nordlund, Toivo Truuts, Miika Meretoja, and Kimmo K. Kahma
Atmos. Chem. Phys., 21, 18175–18194, https://doi.org/10.5194/acp-21-18175-2021, https://doi.org/10.5194/acp-21-18175-2021, 2021
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Ship emissions play an important role in the deposition of gaseous compounds and nanoparticles (Ntot), affecting climate, human health (especially in coastal areas), and eutrophication. Micrometeorological methods showed that ship emissions were mainly responsible for the deposition of Ntot, whereas they only accounted for a minor proportion of CO2 deposition. An uncertainty analysis applied to the fluxes and fuel sulfur content results demonstrated the reliability of the results.
Ingeborg Levin, Ute Karstens, Samuel Hammer, Julian DellaColetta, Fabian Maier, and Maksym Gachkivskyi
Atmos. Chem. Phys., 21, 17907–17926, https://doi.org/10.5194/acp-21-17907-2021, https://doi.org/10.5194/acp-21-17907-2021, 2021
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The radon tracer method is applied to atmospheric methane and radon observations from the upper Rhine valley to independently estimate methane emissions from the region. Comparison of our top-down results with bottom-up inventory data requires high-resolution footprint modelling and representative radon flux data. In agreement with inventories, observed emissions decreased, but only until 2005. A limitation of this method is that point-source emissions are not captured or not fully captured.
Zhixiong Chen, Jane Liu, Xugeng Cheng, Mengmiao Yang, and Hong Wang
Atmos. Chem. Phys., 21, 16911–16923, https://doi.org/10.5194/acp-21-16911-2021, https://doi.org/10.5194/acp-21-16911-2021, 2021
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Using a large ensemble of typhoons, we investigate the impacts of evolving typhoons on tropospheric ozone and address the linkages between typhoon-affected meteorological conditions and ozone variations. The influences of typhoon-induced stratospheric intrusions on lower-troposphere ozone are also quantified. Thus, the results obtained in this study have important implications for a full understanding of the multifaced roles of typhoons in modulating tropospheric ozone variation.
Yang Yang, Minqiang Zhou, Ting Wang, Bo Yao, Pengfei Han, Denghui Ji, Wei Zhou, Yele Sun, Gengchen Wang, and Pucai Wang
Atmos. Chem. Phys., 21, 11741–11757, https://doi.org/10.5194/acp-21-11741-2021, https://doi.org/10.5194/acp-21-11741-2021, 2021
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This study introduces the in situ CO2 measurement system installed in Beijing (urban), Xianghe (suburban), and Xinglong (rural) in North China for the first time. The spatial and temporal variations in CO2 mole fractions at the three sites between June 2018 and April 2020 are discussed on both seasonal and diurnal scales.
Dmitry V. Ionov, Maria V. Makarova, Frank Hase, Stefani C. Foka, Vladimir S. Kostsov, Carlos Alberti, Thomas Blumenstock, Thorsten Warneke, and Yana A. Virolainen
Atmos. Chem. Phys., 21, 10939–10963, https://doi.org/10.5194/acp-21-10939-2021, https://doi.org/10.5194/acp-21-10939-2021, 2021
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Megacities are a significant source of emissions of various substances in the atmosphere, including carbon dioxide, which is the most important anthropogenic greenhouse gas. In 2019–2020, the Emission Monitoring Mobile Experiment was carried out in St Petersburg, which is the second-largest industrial city in Russia. The results of this experiment, coupled with numerical modelling, helped to estimate the amount of CO2 emitted by the city. This value was twice as high as predicted.
Cheng Hu, Jiaping Xu, Cheng Liu, Yan Chen, Dong Yang, Wenjing Huang, Lichen Deng, Shoudong Liu, Timothy J. Griffis, and Xuhui Lee
Atmos. Chem. Phys., 21, 10015–10037, https://doi.org/10.5194/acp-21-10015-2021, https://doi.org/10.5194/acp-21-10015-2021, 2021
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Seventy percent of global CO2 emissions were emitted from urban landscapes. The Yangtze River delta (YRD) ranks as one of the most densely populated regions in the world and is an anthropogenic CO2 hotspot. Besides anthropogenic factors, natural ecosystems and croplands act as significant CO2 sinks and sources. Independent quantification of the fossil and cement CO2 emission and assessment of their impact on atmospheric δ13C-CO2 have potential to improve our understanding of urban CO2 cycling.
Cited articles
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Kalabokas, P. D., Thouret, V., Cammas, J. P., Volz-Thomas, A., Boulanger, D., and Repapis, C. C.: The geographical distribution of meteorological parameters associated with high and low summer ozone levels in the lower troposphere and the boundary layer over the eastern Mediterranean (Cairo case), Tellus B, 67, 27853, https://doi.org/10.3402/Tellusb.V67.27853, 2015.
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Lin, C.-H., Wu, Y.-L., and Lai, C.-H.: Ozone reservoir layers in a coastal environment – a case study in southern Taiwan, Atmos. Chem. Phys., 10, 4439–4452, https://doi.org/10.5194/acp-10-4439-2010, 2010.
Lin, H., Xing, C., Hong, Q., Liu, C., Ji, X., Liu, T., Lin, J., Lu, C., Tan, W., Li, Q., and Liu, H.: Diagnosis of Ozone Formation Sensitivities in Different Height Layers via MAX-DOAS Observations in Guangzhou, J. Geophys. Res.-Atmos., 127, e2022JD036803, https://doi.org/10.1029/2022jd036803, 2022.
Liu, Z., Zha, F., Wang, Y., Yuan, B., Liu, B., and Tang, G.: Vertical evolution of the concentrations and sources of volatile organic compounds in the lower boundary layer in urban Beijing in summer, Chemosphere, 332, 138767, https://doi.org/10.1016/j.chemosphere.2023.138767, 2023.
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Petetin, H., Sauvage, B., Smit, H. G. J., Gheusi, F., Lohou, F., Blot, R., Clark, H., Athier, G., Boulanger, D., Cousin, J.-M., Nedelec, P., Neis, P., Rohs, S., and Thouret, V.: A climatological view of the vertical stratification of RH, O3 and CO within the PBL and at the interface with free troposphere as seen by IAGOS aircraft and ozonesondes at northern mid-latitudes over 1994–2016, Atmos. Chem. Phys., 18, 9561–9581, https://doi.org/10.5194/acp-18-9561-2018, 2018.
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Short summary
This study collected 1897 ozonesondes from two Chinese megacities (Beijing and Hong Kong) in 2000–2022 to investigate the climatological vertical heterogeneity of lower-tropospheric ozone distribution with a mixing-layer-height-referenced (h-referenced) vertical coordinate system. This vertical coordinate system highlighted O3 stratification features existing at the mixing layer–free troposphere interface and provided a better understanding of O3 pollution in urban regions.
This study collected 1897 ozonesondes from two Chinese megacities (Beijing and Hong Kong) in...
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