Articles | Volume 21, issue 5
https://doi.org/10.5194/acp-21-4025-2021
© Author(s) 2021. 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-21-4025-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Mar 2021
Research article |
| 17 Mar 2021
| 17 Mar 2021
Impact of reduced anthropogenic emissions during COVID-19 on air quality in India
Mengyuan Zhang
Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
Arpit Katiyar
Department of Civil Engineering, Indian Institute of Technology, Delhi, 110016, India
Shengqiang Zhu
Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
Juanyong Shen
School of Environmental Science and Engineering, Shanghai Jiao Tong
University, Shanghai 200240, China
Department of Civil and Environmental Engineering, The Hong Kong
Polytechnic University, Hong Kong SAR, 99907, China
Jinlong Ma
Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
Sri Harsha Kota
Department of Civil Engineering, Indian Institute of Technology, Delhi, 110016, India
Department of Civil and Environmental Engineering, The Hong Kong
Polytechnic University, Hong Kong SAR, 99907, China
Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
Institute of Eco-Chongming (IEC), Shanghai 200062, China
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Shuai Wang, Mengyuan Zhang, Yueqi Gao, Peng Wang, Qingyan Fu, and Hongliang Zhang
Geosci. Model Dev., 17, 3617–3629, https://doi.org/10.5194/gmd-17-3617-2024, https://doi.org/10.5194/gmd-17-3617-2024, 2024
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Numerical models are widely used in air pollution modeling but suffer from significant biases. The machine learning model designed in this study shows high efficiency in identifying such biases. Meteorology (relative humidity and cloud cover), chemical composition (secondary organic components and dust aerosols), and emission sources (residential activities) are diagnosed as the main drivers of bias in modeling PM2.5, a typical air pollutant. The results will help to improve numerical models.
Bin Luo, Yuqiang Zhang, Tao Tang, Hongliang Zhang, Jianlin Hu, Jiangshan Mu, Wenxing Wang, and Likun Xue
EGUsphere, https://doi.org/10.5194/egusphere-2024-974, https://doi.org/10.5194/egusphere-2024-974, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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India is facing a severe air pollution crisis that poses significant health risks, particularly from PM2.5 and O3. Our study reveals rising levels of both pollutants from 1995 to 2014, leading to increased premature mortality. While anthropogenic emissions play a significant role, biomass burning also impacts air quality, in particular seasons and regions in India. This study highlights the urgent need for localized policies to protect public health amid escalating environmental challenges.
Jianing Dai, Guy P. Brasseur, Mihalis Vrekoussis, Maria Kanakidou, Kun Qu, Yijuan Zhang, Hongliang Zhang, and Tao Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-693, https://doi.org/10.5194/egusphere-2024-693, 2024
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This paper employs a regional chemical transport model to quantify the sensitivity of air pollutants and photochemical parameters to specified emission reductions in China for conditions of winter and summer as representative. The study provides insights into the further air quality control in China with reduced primary emissions.
Shuai Wang, Mengyuan Zhang, Hui Zhao, Peng Wang, Sri Harsha Kota, Qingyan Fu, Cong Liu, and Hongliang Zhang
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-34, https://doi.org/10.5194/essd-2024-34, 2024
Revised manuscript accepted for ESSD
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Long-term, open-source, gap-free daily ground-level PM2.5 and PM10 datasets for India (LongPMInd) were reconstructed using a robust machine learning model to support health assessment and air quality management.
Yifan Jiang, Men Xia, Zhe Wang, Penggang Zheng, Yi Chen, and Tao Wang
Atmos. Chem. Phys., 23, 14813–14828, https://doi.org/10.5194/acp-23-14813-2023, https://doi.org/10.5194/acp-23-14813-2023, 2023
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This study provides the first estimate of high rates of formic acid (HCOOH) production from the photochemical aging of real ambient particles and demonstrates the potential importance of this pathway in the formation of HCOOH under ambient conditions. Incorporating this pathway significantly improved the performance of a widely used chemical model. Our solution irradiation experiments demonstrated the importance of nitrate photolysis in HCOOH production via the production of oxidants.
Jianing Dai, Guy P. Brasseur, Mihalis Vrekoussis, Maria Kanakidou, Kun Qu, Yijuan Zhang, Hongliang Zhang, and Tao Wang
Atmos. Chem. Phys., 23, 14127–14158, https://doi.org/10.5194/acp-23-14127-2023, https://doi.org/10.5194/acp-23-14127-2023, 2023
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In this study, we used a regional chemical transport model to characterize the different parameters of atmospheric oxidative capacity in recent chemical environments in China. These parameters include the production and destruction rates of ozone and other oxidants, the ozone production efficiency, the OH reactivity, and the length of the reaction chain responsible for the formation of ozone and ROx. They are also affected by the aerosol burden in the atmosphere.
Qianqian Gao, Shengqiang Zhu, Kaili Zhou, Jinghao Zhai, Shaodong Chen, Qihuang Wang, Shurong Wang, Jin Han, Xiaohui Lu, Hong Chen, Liwu Zhang, Lin Wang, Zimeng Wang, Xin Yang, Qi Ying, Hongliang Zhang, Jianmin Chen, and Xiaofei Wang
Atmos. Chem. Phys., 23, 13049–13060, https://doi.org/10.5194/acp-23-13049-2023, https://doi.org/10.5194/acp-23-13049-2023, 2023
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Dust is a major source of atmospheric aerosols. Its chemical composition is often assumed to be similar to the parent soil. However, this assumption has not been rigorously verified. Dust aerosols are mainly generated by wind erosion, which may have some chemical selectivity. Mn, Cd and Pb were found to be highly enriched in fine-dust (PM2.5) aerosols. In addition, estimation of heavy metal emissions from dust generation by air quality models may have errors without using proper dust profiles.
Xiaodong Xie, Jianlin Hu, Momei Qin, Song Guo, Min Hu, Dongsheng Ji, Hongli Wang, Shengrong Lou, Cheng Huang, Chong Liu, Hongliang Zhang, Qi Ying, Hong Liao, and Yuanhang Zhang
Atmos. Chem. Phys., 23, 10563–10578, https://doi.org/10.5194/acp-23-10563-2023, https://doi.org/10.5194/acp-23-10563-2023, 2023
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The atmospheric age of particles reflects how long particles have been formed and suspended in the atmosphere, which is closely associated with the evolution processes of particles. An analysis of the atmospheric age of PM2.5 provides a unique perspective on the evolution processes of different PM2.5 components. The results also shed lights on how to design effective emission control actions under unfavorable meteorological conditions.
Zhouxing Zou, Qianjie Chen, Men Xia, Qi Yuan, Yi Chen, Yanan Wang, Enyu Xiong, Zhe Wang, and Tao Wang
Atmos. Chem. Phys., 23, 7057–7074, https://doi.org/10.5194/acp-23-7057-2023, https://doi.org/10.5194/acp-23-7057-2023, 2023
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We present OH observation and model simulation results at a coastal site in Hong Kong. The model predicted the OH concentration under high-NOx well but overpredicted it under low-NOx conditions. This implies an insufficient understanding of OH chemistry under low-NOx conditions. We show evidence of missing OH sinks as a possible cause of the overprediction.
Yishuo Guo, Chenjuan Deng, Aino Ovaska, Feixue Zheng, Chenjie Hua, Junlei Zhan, Yiran Li, Jin Wu, Zongcheng Wang, Jiali Xie, Ying Zhang, Tingyu Liu, Yusheng Zhang, Boying Song, Wei Ma, Yongchun Liu, Chao Yan, Jingkun Jiang, Veli-Matti Kerminen, Men Xia, Tuomo Nieminen, Wei Du, Tom Kokkonen, and Markku Kulmala
Atmos. Chem. Phys., 23, 6663–6690, https://doi.org/10.5194/acp-23-6663-2023, https://doi.org/10.5194/acp-23-6663-2023, 2023
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Using the comprehensive datasets, we investigated the long-term variations of air pollutants during winter in Beijing from 2019 to 2022 and analyzed the characteristics of atmospheric pollution cocktail during different short-term special events (e.g., Beijing Winter Olympics, COVID lockdown and Chinese New Year) associated with substantial emission reductions. Our results are useful in planning more targeted and sustainable long-term pollution control plans.
Jinlong Ma, Shengqiang Zhu, Siyu Wang, Peng Wang, Jianmin Chen, and Hongliang Zhang
Atmos. Chem. Phys., 23, 4311–4325, https://doi.org/10.5194/acp-23-4311-2023, https://doi.org/10.5194/acp-23-4311-2023, 2023
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An updated version of the CMAQ model with biogenic volatile organic compound (BVOC) emissions from MEGAN was applied to study the impacts of different land cover inputs on O3 and secondary organic aerosol (SOA) in China. The estimated BVOC emissions ranged from 25.42 to 37.39 Tg using different leaf area index (LAI) and land cover (LC) inputs. Those differences further induced differences of 4.8–6.9 ppb in O3 concentrations and differences of 5.3–8.4 µg m−3 in SOA concentrations in China.
Peng Wang, Ruhan Zhang, Shida Sun, Meng Gao, Bo Zheng, Dan Zhang, Yanli Zhang, Gregory R. Carmichael, and Hongliang Zhang
Atmos. Chem. Phys., 23, 2983–2996, https://doi.org/10.5194/acp-23-2983-2023, https://doi.org/10.5194/acp-23-2983-2023, 2023
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In China, the number of vehicles has jumped significantly in the last decade. This caused severe traffic congestion and aggravated air pollution. In this study, we developed a new temporal allocation approach to quantify the impacts of traffic congestion. We found that traffic congestion worsens air quality and the health burden across China, especially in the urban clusters. More effective and comprehensive vehicle emission control policies should be implemented to improve air quality in China.
Peng Wang, Juanyong Shen, Men Xia, Shida Sun, Yanli Zhang, Hongliang Zhang, and Xinming Wang
Atmos. Chem. Phys., 21, 10347–10356, https://doi.org/10.5194/acp-21-10347-2021, https://doi.org/10.5194/acp-21-10347-2021, 2021
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Ozone (O3) pollution has received extensive attention due to worsening air quality and rising health risks. The Chinese National Day holiday (CNDH), which is associated with intensive commercial and tourist activities, serves as a valuable experiment to evaluate the O3 response during the holiday. We find sharply increasing trends of observed O3 concentrations throughout China during the CNDH, leading to 33 % additional total daily deaths.
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.
Jinlong Ma, Juanyong Shen, Peng Wang, Shengqiang Zhu, Yu Wang, Pengfei Wang, Gehui Wang, Jianmin Chen, and Hongliang Zhang
Atmos. Chem. Phys., 21, 7343–7355, https://doi.org/10.5194/acp-21-7343-2021, https://doi.org/10.5194/acp-21-7343-2021, 2021
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Due to the reduced anthropogenic emissions during the COVID-19 lockdown, mainly from the transportation and industrial sectors, PM2.5 decreased significantly in the whole Yangtze River Delta (YRD) and its major cities. However, the contributions and relative importance of different source sectors and regions changed differently, indicating that control strategies should be adjusted accordingly for further pollution control.
Junjun Deng, Hao Guo, Hongliang Zhang, Jialei Zhu, Xin Wang, and Pingqing Fu
Atmos. Chem. Phys., 20, 14419–14435, https://doi.org/10.5194/acp-20-14419-2020, https://doi.org/10.5194/acp-20-14419-2020, 2020
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One-year source apportionment of BC aerosols in a coastal city in China was conducted with the light-absorption observation-based method and source-oriented model. Source contributions identified by the two source apportionment methods were compared. Temporal variability, potential sources and transport pathways of BC from fossil fuel and biomass burning were characterized. Significant influence of biomass burning in North and East–Central China on BC in the region was highlighted.
Zhihao Shi, Lin Huang, Jingyi Li, Qi Ying, Hongliang Zhang, and Jianlin Hu
Atmos. Chem. Phys., 20, 13455–13466, https://doi.org/10.5194/acp-20-13455-2020, https://doi.org/10.5194/acp-20-13455-2020, 2020
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Meteorological conditions play important roles in the formation of O3 and PM2.5 pollution in China. O3 is most sensitive to temperature and the sensitivity is dependent on the O3 chemistry formation or loss regime. PM2.5 is negatively sensitive to temperature, wind speed, and planetary boundary layer height and positively sensitive to humidity. The results imply that air quality in certain regions of China is sensitive to climate changes.
Shengqiang Zhu, Lei Li, Shurong Wang, Mei Li, Yaxi Liu, Xiaohui Lu, Hong Chen, Lin Wang, Jianmin Chen, Zhen Zhou, Xin Yang, and Xiaofei Wang
Atmos. Meas. Tech., 13, 4111–4121, https://doi.org/10.5194/amt-13-4111-2020, https://doi.org/10.5194/amt-13-4111-2020, 2020
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Single-particle aerosol mass spectrometry (SPAMS) is widely used to detect chemical compositions and sizes of individual aerosol particles. However, it has a major issue: the mass accuracy of high-resolution SPAMS is relatively low. Here we developed an automatic linear calibration method to greatly improve the mass accuracy of SPAMS spectra so that the elemental compositions of organic peaks, such as Cx, CxHy, CxHyOz and CxHyNO peaks, can be directly identified just based on their m / z values.
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.
Chuan Yu, Zhe Wang, Men Xia, Xiao Fu, Weihao Wang, Yee Jun Tham, Tianshu Chen, Penggang Zheng, Hongyong Li, Ye Shan, Xinfeng Wang, Likun Xue, Yan Zhou, Dingli Yue, Yubo Ou, Jian Gao, Keding Lu, Steven S. Brown, Yuanhang Zhang, and Tao Wang
Atmos. Chem. Phys., 20, 4367–4378, https://doi.org/10.5194/acp-20-4367-2020, https://doi.org/10.5194/acp-20-4367-2020, 2020
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This study provides a holistic picture of N2O5 heterogeneous uptake on ambient aerosols and the influencing factors under various climatic and chemical conditions in China, and it proposes an observation-based empirical parameterization. The empirical parameterization can be used in air quality models to improve the prediction of PM2.5 and photochemical pollution in China and similar polluted regions of the world.
Tao Li, Zhe Wang, Yaru Wang, Chen Wu, Yiheng Liang, Men Xia, Chuan Yu, Hui Yun, Weihao Wang, Yan Wang, Jia Guo, Hartmut Herrmann, and Tao Wang
Atmos. Chem. Phys., 20, 391–407, https://doi.org/10.5194/acp-20-391-2020, https://doi.org/10.5194/acp-20-391-2020, 2020
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This work presents a field study of cloud water chemistry and interactions of cloud, gas, and aerosols in the polluted coastal boundary layer in southern China. Substantial dissolved organic matter in the acidic cloud water was observed, and the gas- and aqueous-phase partitioning of carbonyl compounds was investigated. The results demonstrated the significant role of cloud processing in altering aerosol properties, especially in producing aqueous organics and droplet-mode aerosols.
Xue Qiao, Hao Guo, Ya Tang, Pengfei Wang, Wenye Deng, Xing Zhao, Jianlin Hu, Qi Ying, and Hongliang Zhang
Atmos. Chem. Phys., 19, 5791–5803, https://doi.org/10.5194/acp-19-5791-2019, https://doi.org/10.5194/acp-19-5791-2019, 2019
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A source-oriented version of the CMAQ model was used to quantify contributions from nine regions to PM2.5 and its components in the 18 cities within Sichuan Basin. Nonlocal emissions contribute 39–66 % and 25–52 % to the citywide average PM2.5 concentrations of 45–126 and 14–31 µg m3 in the winter and summer, respectively. This study demonstrates the importance of joint emission control efforts among cities within the SCB and neighboring regions to the east.
Xiao Fu, Tao Wang, Li Zhang, Qinyi Li, Zhe Wang, Men Xia, Hui Yun, Weihao Wang, Chuan Yu, Dingli Yue, Yan Zhou, Junyun Zheng, and Rui Han
Atmos. Chem. Phys., 19, 1–14, https://doi.org/10.5194/acp-19-1-2019, https://doi.org/10.5194/acp-19-1-2019, 2019
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This study has identified the major contributors to the observed high HONO levels during a severe winter pollution episode and highlighted the importance of HONO chemistry in the combined photochemical and haze pollution in a subtropical region. It also highlighted the critical need to include and update HONO sources in regional air quality models in order to predict ozone and other secondary pollutants better during heavy pollution events in southern China and similar regions.
Hui Yun, Weihao Wang, Tao Wang, Men Xia, Chuan Yu, Zhe Wang, Steven C. N. Poon, Dingli Yue, and Yan Zhou
Atmos. Chem. Phys., 18, 17515–17527, https://doi.org/10.5194/acp-18-17515-2018, https://doi.org/10.5194/acp-18-17515-2018, 2018
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Based on the data analysis of simultaneous measurement of N2O5 and ClNO2 in a severe winter haze in the Pearl River Delta, this study underscores the importance of N2O5 heterogeneous reactions in nitrate formation and calls for better parameterization of N2O5 heterogeneous chemistry in order to predict haze pollution in China.
Hao Guo, Sri Harsha Kota, Kaiyu Chen, Shovan Kumar Sahu, Jianlin Hu, Qi Ying, Yuan Wang, and Hongliang Zhang
Atmos. Chem. Phys., 18, 15219–15229, https://doi.org/10.5194/acp-18-15219-2018, https://doi.org/10.5194/acp-18-15219-2018, 2018
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A total of 1.04 million premature mortalities and up to 2 years of life lost (YLL) per person were estimated in India in 2015 due to PM2.5. Premature mortality due to cerebrovascular disease (CEVD) was the highest (0.44 million), followed by ischaemic heart disease (IHD, 0.40 million). The residential sector was the largest contributor, followed by industry, agriculture and energy. Reducing PM2.5 concentrations would lead to a significant reduction in premature mortality and YLL.
Weihao Wang, Zhe Wang, Chuan Yu, Men Xia, Xiang Peng, Yan Zhou, Dingli Yue, Yubo Ou, and Tao Wang
Atmos. Meas. Tech., 11, 5643–5655, https://doi.org/10.5194/amt-11-5643-2018, https://doi.org/10.5194/amt-11-5643-2018, 2018
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This study introduces an in situ experimental approach to direct measurement of N2O5 heterogeneous reactivity in polluted environments. Laboratory tests, model simulations, and field deployment of the method at a polluted site in south China demonstrated its applicability in accurately measuring N2O5 uptake coefficient with high ambient pollutants levels and air mass changes. The introduced method is also applicable to in situ measurement of reactivity of other trace gases on ambient aerosols.
Mingjie Kang, Pingqing Fu, Kimitaka Kawamura, Fan Yang, Hongliang Zhang, Zhengchen Zang, Hong Ren, Lujie Ren, Ye Zhao, Yele Sun, and Zifa Wang
Atmos. Chem. Phys., 18, 13947–13967, https://doi.org/10.5194/acp-18-13947-2018, https://doi.org/10.5194/acp-18-13947-2018, 2018
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Molecular characterization and spatial distribution of biogenic primary organic aerosol (POA) and secondary organic aerosol (SOA) in the marine atmosphere are not well known. Here, we analysed the organic molecular composition of marine aerosols collected during a marine cruise in the East China Sea during May–June 2014. Our results suggest that the Asian continent can be a natural emitter of biogenic POA and SOA, which can be transported to the downwind marine atmosphere.
Congbo Song, Yan Liu, Shida Sun, Luna Sun, Yanjie Zhang, Chao Ma, Jianfei Peng, Qian Li, Jinsheng Zhang, Qili Dai, Baoshuang Liu, Peng Wang, Yi Zhang, Ting Wang, Lin Wu, Min Hu, and Hongjun Mao
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-387, https://doi.org/10.5194/acp-2018-387, 2018
Revised manuscript not accepted
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Vehicular emission is a key contributor to ambient volatile organic compounds (VOCs) and NOx in Chinese megacities. Information on real-world emission factors (EFs) for a typical urban fleet is still limited. We found that improvement of fuel quality can significantly reduce feet-average EFs of VOCs (especially for BTEX). Our study provided implications for O3 control in China from the view of primary emission, and highlighted the importance of further control of evaporative emissions.
Jianlin Hu, Xun Li, Lin Huang, Qi Ying, Qiang Zhang, Bin Zhao, Shuxiao Wang, and Hongliang Zhang
Atmos. Chem. Phys., 17, 13103–13118, https://doi.org/10.5194/acp-17-13103-2017, https://doi.org/10.5194/acp-17-13103-2017, 2017
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The model performance of CMAQ with WRF using four different emission inventories in China was validated and compared to obtain the best air pollutants prediction for health effect studies of severe air pollution. The differences in performance of chemical transport model were analyzed for different months and regions in the vast part of China and ensemble predictions were firstly obtained from different inventories for health analysis with minimized errors for pollutants including PM2.5 and O3.
Jianlin Hu, Shantanu Jathar, Hongliang Zhang, Qi Ying, Shu-Hua Chen, Christopher D. Cappa, and Michael J. Kleeman
Atmos. Chem. Phys., 17, 5379–5391, https://doi.org/10.5194/acp-17-5379-2017, https://doi.org/10.5194/acp-17-5379-2017, 2017
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Organic aerosol is a major constituent of ultrafine particulate matter (PM0.1). In this study, a source-oriented air quality model was used to simulate the concentrations and sources of primary and secondary organic aerosols in PM0.1 in California for a 9-year modeling period to provide useful information for epidemiological studies to further investigate the associations with health outcomes.
Jianlin Hu, Peng Wang, Qi Ying, Hongliang Zhang, Jianjun Chen, Xinlei Ge, Xinghua Li, Jingkun Jiang, Shuxiao Wang, Jie Zhang, Yu Zhao, and Yingyi Zhang
Atmos. Chem. Phys., 17, 77–92, https://doi.org/10.5194/acp-17-77-2017, https://doi.org/10.5194/acp-17-77-2017, 2017
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An annual simulation of secondary organic aerosol (SOA) concentrations in China with updated SOA formation pathways reveals that SOA can be a significant contributor to PM2.5 in major urban areas. Summer SOA is dominated by emissions from biogenic sources, while winter SOA is dominated by anthropogenic emissions such as alkanes and aromatic compounds. Reactive surface uptake of dicarbonyls throughout the year and isoprene epoxides in summer is the most important contributor.
Jianlin Hu, Jianjun Chen, Qi Ying, and Hongliang Zhang
Atmos. Chem. Phys., 16, 10333–10350, https://doi.org/10.5194/acp-16-10333-2016, https://doi.org/10.5194/acp-16-10333-2016, 2016
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A yearlong (2013) air-quality simulation was conducted to provide detailed temporal and spatial information of ozone, PM2.5 total and chemical components. The paper firstly compared the simulated air pollutants in China with country-wide public available observations for a whole year. It proves the ability of CMAQ in reproducing severe air pollution in China, shows directions that need to be improved, and benefits future source apportionment and human exposure studies.
Hsiang-He Lee, Shu-Hua Chen, Michael J. Kleeman, Hongliang Zhang, Steven P. DeNero, and David K. Joe
Atmos. Chem. Phys., 16, 8353–8374, https://doi.org/10.5194/acp-16-8353-2016, https://doi.org/10.5194/acp-16-8353-2016, 2016
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A source-oriented CCN module was implemented in a source-oriented chemistry model to study the effect of aerosol mixing state on fog formation. The fraction of aerosols activating into CCN at a supersaturation of 0.5 % in the Central Valley decreased from 94 % in the internal mixture model to 80 % in the source-oriented model. The internal mixture model predicted greater CCN activation than the source-oriented model due to artificial coating of hydrophobic particles with hygroscopic components.
J. Hu, H. Zhang, Q. Ying, S.-H. Chen, F. Vandenberghe, and M. J. Kleeman
Atmos. Chem. Phys., 15, 3445–3461, https://doi.org/10.5194/acp-15-3445-2015, https://doi.org/10.5194/acp-15-3445-2015, 2015
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Air quality model simulations have been conducted for California from 2000 to 2009 with 4km spatial resolution to provide exposure data for health effect studies. Comprehensive analysis shows that predicted concentrations for many pollutants are in agreement with measurements at monitoring stations, building confidence that the fields may be useful at times and locations where measurements are not available. Data can be downloaded for free at http://faculty.engineering.ucdavis.edu/kleeman/.
H. Zhang, S. P. DeNero, D. K. Joe, H.-H. Lee, S.-H. Chen, J. Michalakes, and M. J. Kleeman
Atmos. Chem. Phys., 14, 485–503, https://doi.org/10.5194/acp-14-485-2014, https://doi.org/10.5194/acp-14-485-2014, 2014
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Revealing the significant acceleration of hydrofluorocarbon (HFC) emissions in eastern Asia through long-term atmospheric observations
Interpreting Geostationary Environment Monitoring Spectrometer (GEMS) geostationary satellite observations of the diurnal variation in nitrogen dioxide (NO2) over East Asia
An intercomparison of satellite, airborne, and ground-level observations with WRF–CAMx simulations of NO2 columns over Houston, Texas, during the September 2021 TRACER-AQ campaign
Interannual variability of summertime formaldehyde (HCHO) vertical column density and its main drivers at northern high latitudes
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Combined assimilation of NOAA surface and MIPAS satellite observations to constrain the global budget of carbonyl sulfide
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MIXv2: a long-term mosaic emission inventory for Asia (2010–2017)
Organosulfate produced from consumption of SO3 speeds up sulfuric acid–dimethylamine atmospheric nucleation
Contribution of expanded marine sulfur chemistry to the seasonal variability of dimethyl sulfide oxidation products and size-resolved sulfate aerosol
Development of a detailed gaseous oxidation scheme of naphthalene for SOA formation and speciation
Spatial disparities of ozone pollution in the Sichuan Basin spurred by extreme, hot weather
Global impacts of aviation on air quality evaluated at high resolution
Enhancing Long-Term Trend Simulation of Global Tropospheric OH and Its Drivers from 2005–2019: A Synergistic Integration of Model Simulations and Satellite Observations
Large contribution of soil emissions to the atmospheric nitrogen budget and their impacts on air quality and temperature rise in North China
Bias correction of OMI HCHO columns based on FTIR and aircraft measurements and impact on top-down emission estimates
Intercomparison of GEOS-Chem and CAM-chem tropospheric oxidant chemistry within the Community Earth System Model version 2 (CESM2)
Investigation of the renewed methane growth post-2007 with high-resolution 3-D variational inverse modeling and isotopic constraints
NOx emissions in France in 2019–2021 as estimated by the high spatial resolution assimilation of TROPOMI NO2 observations
Estimating NOx emissions of stack plumes using a high-resolution atmospheric chemistry model and satellite-derived NO2 columns
Revisiting day-of-week ozone patterns in an era of evolving US air quality
Changes in South American Surface Ozone Trends: Exploring the Influences of Precursors and Extreme Events
Air quality and radiative impacts of downward-propagating sudden stratospheric warmings (SSWs)
Estimation of the atmospheric hydroxyl radical oxidative capacity using multiple hydrofluorocarbons (HFCs)
Investigating the differences in calculating global mean surface CO2 abundance: the impact of analysis methodologies and site selection
Meteorological characteristics of extreme ozone pollution events in China and their future predictions
Evaluating modelled tropospheric columns of CH4, CO, and O3 in the Arctic using ground-based Fourier transform infrared (FTIR) measurements
Evaluation of modelled versus observed NMVOC compounds at EMEP sites in Europe
The high-resolution Global Aviation emissions Inventory based on ADS-B (GAIA) for 2019–2021
Zonal variability of methane trends derived from satellite data
Weekly derived top-down volatile-organic-compound fluxes over Europe from TROPOMI HCHO data from 2018 to 2021
Current status of model predictions of volatile organic compounds and impacts on surface ozone predictions during summer in China
Utility of Geostationary Lightning Mapper-derived lightning NO emission estimates in air quality modeling studies
Constraint of non-methane volatile organic compound emissions with TROPOMI HCHO observations and its impact on summertime surface ozone simulation over China
The suitability of atmospheric oxygen measurements to constrain western European fossil-fuel CO2 emissions and their trends
Identifying decadal trends in deweathered concentrations of criteria air pollutants in Canadian urban atmospheres with machine learning approaches
Future tropospheric ozone budget and distribution over east Asia under a net-zero scenario
Why Did Ozone Concentrations Increase During Shanghai’s Static Management? A Statistical and Radical Chemistry Perspective
Comprehensive multiphase chlorine chemistry in the box model CAABA/MECCA: implications for atmospheric oxidative capacity
Insights into soil NO emissions and the contribution to surface ozone formation in China
Development, intercomparison, and evaluation of an improved mechanism for the oxidation of dimethyl sulfide in the UKCA model
Haklim Choi, Alison L. Redington, Hyeri Park, Jooil Kim, Rona L. Thompson, Jens Mühle, Peter K. Salameh, Christina M. Harth, Ray F. Weiss, Alistair J. Manning, and Sunyoung Park
Atmos. Chem. Phys., 24, 7309–7330, https://doi.org/10.5194/acp-24-7309-2024, https://doi.org/10.5194/acp-24-7309-2024, 2024
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We analyzed with an inversion model the atmospheric abundance of hydrofluorocarbons (HFCs), potent greenhouse gases, from 2008 to 2020 at Gosan station in South Korea and revealed a significant increase in emissions, especially from eastern China and Japan. This increase contradicts reported data, underscoring the need for accurate monitoring and reporting. Our findings are crucial for understanding and managing global HFCs emissions, highlighting the importance of efforts to reduce HFCs.
Laura Hyesung Yang, Daniel J. Jacob, Ruijun Dang, Yujin J. Oak, Haipeng Lin, Jhoon Kim, Shixian Zhai, Nadia K. Colombi, Drew C. Pendergrass, Ellie Beaudry, Viral Shah, Xu Feng, Robert M. Yantosca, Heesung Chong, Junsung Park, Hanlim Lee, Won-Jin Lee, Soontae Kim, Eunhye Kim, Katherine R. Travis, James H. Crawford, and Hong Liao
Atmos. Chem. Phys., 24, 7027–7039, https://doi.org/10.5194/acp-24-7027-2024, https://doi.org/10.5194/acp-24-7027-2024, 2024
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The Geostationary Environment Monitoring Spectrometer (GEMS) provides hourly measurements of NO2. We use the chemical transport model to find how emissions, chemistry, and transport drive the changes in NO2 observed by GEMS at different times of the day. In winter, the chemistry plays a minor role, and high daytime emissions dominate the diurnal variation in NO2, balanced by transport. In summer, emissions, chemistry, and transport play an important role in shaping the diurnal variation in NO2.
M. Omar Nawaz, Jeremiah Johnson, Greg Yarwood, Benjamin de Foy, Laura Judd, and Daniel L. Goldberg
Atmos. Chem. Phys., 24, 6719–6741, https://doi.org/10.5194/acp-24-6719-2024, https://doi.org/10.5194/acp-24-6719-2024, 2024
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NO2 is a gas with implications for air pollution. A campaign conducted in Houston provided an opportunity to compare NO2 from different instruments and a model. Aircraft and satellite observations agreed well with measurements on the ground; however, the latter estimated lower values. We find that model-simulated NO2 was lower than observations, especially downtown, suggesting that NO2 sources associated with the urban core of Houston, such as vehicle emissions, may be underestimated.
Tianlang Zhao, Jingqiu Mao, Zolal Ayazpour, Gonzalo González Abad, Caroline R. Nowlan, and Yiqi Zheng
Atmos. Chem. Phys., 24, 6105–6121, https://doi.org/10.5194/acp-24-6105-2024, https://doi.org/10.5194/acp-24-6105-2024, 2024
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HCHO variability is a key tracer in understanding VOC emissions in response to climate change. We investigate the role of methane oxidation and biogenic and wildfire emissions in HCHO interannual variability over northern high latitudes in summer, emphasizing wildfires as a key driver of HCHO interannual variability in Alaska, Siberia and northern Canada using satellite HCHO and SIF retrievals and then GEOS-Chem model. We show SIF is a tool to understand biogenic HCHO variability in this region.
Jianghao Li, Alastair C. Lewis, Jim R. Hopkins, Stephen J. Andrews, Tim Murrells, Neil Passant, Ben Richmond, Siqi Hou, William J. Bloss, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 24, 6219–6231, https://doi.org/10.5194/acp-24-6219-2024, https://doi.org/10.5194/acp-24-6219-2024, 2024
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A summertime ozone event at an urban site in Birmingham is sensitive to volatile organic compounds (VOCs) – particularly those of oxygenated VOCs. The roles of anthropogenic VOC sources in urban ozone chemistry are examined by integrating the 1990–2019 national atmospheric emission inventory into model scenarios. Road transport remains the most powerful means of further reducing ozone in this case study, but the benefits may be offset if solvent emissions of VOCs continue to increase.
Kai-Lan Chang, Owen R. Cooper, Audrey Gaudel, Irina Petropavlovskikh, Peter Effertz, Gary Morris, and Brian C. McDonald
Atmos. Chem. Phys., 24, 6197–6218, https://doi.org/10.5194/acp-24-6197-2024, https://doi.org/10.5194/acp-24-6197-2024, 2024
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A great majority of observational trend studies of free tropospheric ozone use sparsely sampled ozonesonde and aircraft measurements as reference data sets. A ubiquitous assumption is that trends are accurate and reliable so long as long-term records are available. We show that sampling bias due to sparse samples can persistently reduce the trend accuracy, and we highlight the importance of maintaining adequate frequency and continuity of observations.
Jin Ma, Linda M. J. Kooijmans, Norbert Glatthor, Stephen A. Montzka, Marc von Hobe, Thomas Röckmann, and Maarten C. Krol
Atmos. Chem. Phys., 24, 6047–6070, https://doi.org/10.5194/acp-24-6047-2024, https://doi.org/10.5194/acp-24-6047-2024, 2024
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The global budget of atmospheric COS can be optimised by inverse modelling using TM5-4DVAR, with the co-constraints of NOAA surface observations and MIPAS satellite data. We found reduced COS biosphere uptake from inversions and improved land and ocean separation using MIPAS satellite data assimilation. Further improvements are expected from better quantification of COS ocean and biosphere fluxes.
Fu-Jie Zhu, Zi-Feng Zhang, Li-Yan Liu, Pu-Fei Yang, Peng-Tuan Hu, Geng-Bo Ren, Meng Qin, and Wan-Li Ma
Atmos. Chem. Phys., 24, 6095–6103, https://doi.org/10.5194/acp-24-6095-2024, https://doi.org/10.5194/acp-24-6095-2024, 2024
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Gas–particle (G–P) partitioning is an important atmospheric behavior for semi-volatile organic compounds (SVOCs). Diurnal variation in G–P partitioning of methylated polycyclic aromatic hydrocarbons (Me-PAHs) demonstrates the possible influence of gaseous degradation; the enhancement of gaseous degradation (1.10–5.58 times) on G–P partitioning is verified by a steady-state G–P partitioning model. The effect of gaseous degradation on G–P partitioning of (especially light) SVOCs is important.
Christoph Staehle, Harald E. Rieder, Arlene M. Fiore, and Jordan L. Schnell
Atmos. Chem. Phys., 24, 5953–5969, https://doi.org/10.5194/acp-24-5953-2024, https://doi.org/10.5194/acp-24-5953-2024, 2024
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Chemistry–climate models show biases compared to surface ozone observations and thus require bias correction for impact studies and the assessment of air quality changes. We compare the performance of commonly used correction techniques for model outputs available via CMIP6. While all methods can reduce model biases, better results are obtained from more complex approaches. Thus, our study suggests broader use of these techniques in studies seeking to inform air quality management and policy.
Qindan Zhu, Rebecca H. Schwantes, Matthew Coggon, Colin Harkins, Jordan Schnell, Jian He, Havala O. T. Pye, Meng Li, Barry Baker, Zachary Moon, Ravan Ahmadov, Eva Y. Pfannerstill, Bryan Place, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Anthony Bucholtz, John H. Seinfeld, Carsten Warneke, Chelsea E. Stockwell, Lu Xu, Kristen Zuraski, Michael A. Robinson, J. Andrew Neuman, Patrick R. Veres, Jeff Peischl, Steven S. Brown, Allen H. Goldstein, Ronald C. Cohen, and Brian C. McDonald
Atmos. Chem. Phys., 24, 5265–5286, https://doi.org/10.5194/acp-24-5265-2024, https://doi.org/10.5194/acp-24-5265-2024, 2024
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Volatile organic compounds (VOCs) fuel the production of air pollutants like ozone and particulate matter. The representation of VOC chemistry remains challenging due to its complexity in speciation and reactions. Here, we develop a chemical mechanism, RACM2B-VCP, that better represents VOC chemistry in urban areas such as Los Angeles. We also discuss the contribution of VOCs emitted from volatile chemical products and other anthropogenic sources to total VOC reactivity and O3.
Hannah Nesser, Daniel J. Jacob, Joannes D. Maasakkers, Alba Lorente, Zichong Chen, Xiao Lu, Lu Shen, Zhen Qu, Melissa P. Sulprizio, Margaux Winter, Shuang Ma, A. Anthony Bloom, John R. Worden, Robert N. Stavins, and Cynthia A. Randles
Atmos. Chem. Phys., 24, 5069–5091, https://doi.org/10.5194/acp-24-5069-2024, https://doi.org/10.5194/acp-24-5069-2024, 2024
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We quantify 2019 methane emissions in the contiguous US (CONUS) at a ≈ 25 km × 25 km resolution using satellite methane observations. We find a 13 % upward correction to the 2023 US Environmental Protection Agency (EPA) Greenhouse Gas Emissions Inventory (GHGI) for 2019, with large corrections to individual states, urban areas, and landfills. This may present a challenge for US climate policies and goals, many of which target significant reductions in methane emissions.
David de la Paz, Rafael Borge, Juan Manuel de Andrés, Luis Tovar, Golam Sarwar, and Sergey L. Napelenok
Atmos. Chem. Phys., 24, 4949–4972, https://doi.org/10.5194/acp-24-4949-2024, https://doi.org/10.5194/acp-24-4949-2024, 2024
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This source apportionment modeling study shows that around 70 % of ground-level O3 in Madrid (Spain) is transported from other regions. Nonetheless, emissions from local sources, mainly road traffic, play a significant role, especially under atmospheric stagnation. Local measures during those conditions may be able to reduce O3 peaks by up to 30 % and, thus, lessen impacts from high-O3 episodes in the Madrid metropolitan area.
Audrey Fortems-Cheiney, Gregoire Broquet, Elise Potier, Robin Plauchu, Antoine Berchet, Isabelle Pison, Hugo Denier van der Gon, and Stijn Dellaert
Atmos. Chem. Phys., 24, 4635–4649, https://doi.org/10.5194/acp-24-4635-2024, https://doi.org/10.5194/acp-24-4635-2024, 2024
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We have estimated the carbon monixide (CO) European emissions from satellite observations of the MOPITT instrument at the relatively high resolution of 0.5° for a period of over 10 years from 2011 to 2021. The analysis of the inversion results reveals the challenges associated with the inversion of CO emissions at the regional scale over Europe.
Amy Christiansen, Loretta J. Mickley, and Lu Hu
Atmos. Chem. Phys., 24, 4569–4589, https://doi.org/10.5194/acp-24-4569-2024, https://doi.org/10.5194/acp-24-4569-2024, 2024
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In this work, we provide an additional constraint on emissions and trends of nitrogen oxides using nitrate wet deposition (NWD) fluxes over the United States and Europe from 1980–2020. We find that NWD measurements constrain total NOx emissions well. We also find evidence of NOx emission overestimates in both domains, but especially over Europe, where NOx emissions are overestimated by a factor of 2. Reducing NOx emissions over Europe improves model representation of ozone at the surface.
Eduardo Torre-Pascual, Gotzon Gangoiti, Ana Rodríguez-García, Estibaliz Sáez de Cámara, Joana Ferreira, Carla Gama, María Carmen Gómez, Iñaki Zuazo, Jose Antonio García, and Maite de Blas
Atmos. Chem. Phys., 24, 4305–4329, https://doi.org/10.5194/acp-24-4305-2024, https://doi.org/10.5194/acp-24-4305-2024, 2024
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We present an analysis of an intense air pollution episode of tropospheric ozone (O3) along the Atlantic coast of the Iberian Peninsula, incorporating both measured and simulated parameters. Our study extends beyond surface-level factors to include altitude-related parameters. These episodes stem from upper-atmosphere O3 accumulation in preceding days, transported to surface layers, causing rapid O3 concentration increase.
Hannah Chawner, Eric Saboya, Karina E. Adcock, Tim Arnold, Yuri Artioli, Caroline Dylag, Grant L. Forster, Anita Ganesan, Heather Graven, Gennadi Lessin, Peter Levy, Ingrid T. Luijkx, Alistair Manning, Penelope A. Pickers, Chris Rennick, Christian Rödenbeck, and Matthew Rigby
Atmos. Chem. Phys., 24, 4231–4252, https://doi.org/10.5194/acp-24-4231-2024, https://doi.org/10.5194/acp-24-4231-2024, 2024
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The quantity of atmospheric potential oxygen (APO), derived from coincident measurements of carbon dioxide (CO2) and oxygen (O2), has been proposed as a tracer for fossil fuel CO2 emissions. In this model sensitivity study, we examine the use of APO for this purpose in the UK and compare our model to observations. We find that our model simulations are most sensitive to uncertainties relating to ocean fluxes and boundary conditions.
Meng Li, Junichi Kurokawa, Qiang Zhang, Jung-Hun Woo, Tazuko Morikawa, Satoru Chatani, Zifeng Lu, Yu Song, Guannan Geng, Hanwen Hu, Jinseok Kim, Owen R. Cooper, and Brian C. McDonald
Atmos. Chem. Phys., 24, 3925–3952, https://doi.org/10.5194/acp-24-3925-2024, https://doi.org/10.5194/acp-24-3925-2024, 2024
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In this work, we developed MIXv2, a mosaic Asian emission inventory for 2010–2017. With high spatial (0.1°) and monthly temporal resolution, MIXv2 integrates anthropogenic and open biomass burning emissions across seven sectors following a mosaic methodology. It provides CO2 emissions data alongside nine key pollutants and three chemical mechanisms. Our publicly accessible gridded monthly emissions data can facilitate long-term atmospheric and climate model analyses.
Xiaomeng Zhang, Yongjian Lian, Shendong Tan, and Shi Yin
Atmos. Chem. Phys., 24, 3593–3612, https://doi.org/10.5194/acp-24-3593-2024, https://doi.org/10.5194/acp-24-3593-2024, 2024
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Atmospheric new particle formation (NPF) has a significant influence on the global climate, local air quality and human health. Using a combination of quantum chemical calculations and kinetics modeling, we find that thhe gas-phase organosulfate produced from consumption of SO3 can significantly enhance SA–DMA nucleation in the polluted boundary layer, resulting in non-negligible contributions to NPF. Our findings provide important insights into organic sulfur in atmospheric aerosol formation.
Linia Tashmim, William C. Porter, Qianjie Chen, Becky Alexander, Charles H. Fite, Christopher D. Holmes, Jeffrey R. Pierce, Betty Croft, and Sakiko Ishino
Atmos. Chem. Phys., 24, 3379–3403, https://doi.org/10.5194/acp-24-3379-2024, https://doi.org/10.5194/acp-24-3379-2024, 2024
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Dimethyl sulfide (DMS) is mostly emitted from ocean surfaces and represents the largest natural source of sulfur for the atmosphere. Once in the atmosphere, DMS forms stable oxidation products such as SO2 and H2SO4, which can subsequently contribute to airborne particle formation and growth. In this study, we update the DMS oxidation mechanism in the chemical transport model GEOS-Chem and describe resulting changes in particle growth as well as the overall global sulfur budget.
Victor Lannuque and Karine Sartelet
EGUsphere, https://doi.org/10.5194/egusphere-2024-711, https://doi.org/10.5194/egusphere-2024-711, 2024
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Large uncertainties remain in understanding secondary organic aerosol (SOA) formation and speciation from naphthalene oxidation. This study details the development of the first near-explicit chemical scheme for naphthalene oxidation by OH including kinetic and mechanistic data and able to reproduce most of the experimentally identified products in both gas and particle phases.
Nan Wang, Yunsong Du, Dongyang Chen, Haiyan Meng, Xi Chen, Li Zhou, Guangming Shi, Yu Zhan, Miao Feng, Wei Li, Mulan Chen, Zhenliang Li, and Fumo Yang
Atmos. Chem. Phys., 24, 3029–3042, https://doi.org/10.5194/acp-24-3029-2024, https://doi.org/10.5194/acp-24-3029-2024, 2024
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In the scorching August 2022 heatwave, China's Sichuan Basin saw a stark contrast in ozone (O3) levels between Chengdu and Chongqing. The regional disparities were studied considering meteorology, precursors, photochemistry, and transportation. The study highlighted the importance of tailored pollution control measures and underlined the necessity for region-specific strategies to combat O3 pollution on a regional scale.
Sebastian D. Eastham, Guillaume P. Chossière, Raymond L. Speth, Daniel J. Jacob, and Steven R. H. Barrett
Atmos. Chem. Phys., 24, 2687–2703, https://doi.org/10.5194/acp-24-2687-2024, https://doi.org/10.5194/acp-24-2687-2024, 2024
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Emissions from aircraft are known to cause air quality impacts worldwide, but the scale and mechanisms of this impact are not well understood. This work uses high-resolution computational modeling of the atmosphere to show that air pollution changes from aviation are mostly the result of emissions during cruise (high-altitude) operations, that these impacts are related to how much non-aviation pollution is present, and that prior regional assessments have underestimated these impacts.
Amir H. Souri, Bryan N. Duncan, Sarah A. Strode, Daniel C. Anderson, Michael E. Manyin, Junhua Liu, Luke D. Oman, Zhen Zhang, and Brad Weir
EGUsphere, https://doi.org/10.5194/egusphere-2024-410, https://doi.org/10.5194/egusphere-2024-410, 2024
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We explore a new method to make use of the wealth of information obtained from satellite observations of Aura OMI NO2, HCHO, along with MERRA2 reanalysis in NASA’s GEOS model equipped with an efficient tropospheric OH (TOH) estimator to enhance the representation of TOH spatial distribution and its long-term trends. This new framework helps us pinpoint regional inaccuracies in TOH and differentiate between established prior knowledge and newly acquired information from satellites on TOH trends.
Tong Sha, Siyu Yang, Qingcai Chen, Liangqing Li, Xiaoyan Ma, Yan-Lin Zhang, Zhaozhong Feng, K. Folkert Boersma, and Jun Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-359, https://doi.org/10.5194/egusphere-2024-359, 2024
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By using an updated soil reactive nitrogen emission scheme in the UI-WRF-Chem model, we investigate the underappreciated role of soil NO and HONO (Nr) emissions on air quality and temperature rise in North China. The significant contributions of soil Nr emissions to O3 and secondary pollutants, exceeding the effects of soil NOx or HONO emission alone. And soil Nr emissions play an important role in mitigating O3 pollution and addressing climate change.
Jean-François Müller, Trissevgeni Stavrakou, Glenn-Michael Oomen, Beata Opacka, Isabelle De Smedt, Alex Guenther, Corinne Vigouroux, Bavo Langerock, Carlos Augusto Bauer Aquino, Michel Grutter, James Hannigan, Frank Hase, Rigel Kivi, Erik Lutsch, Emmanuel Mahieu, Maria Makarova, Jean-Marc Metzger, Isamu Morino, Isao Murata, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Amelie Röhling, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, and Alan Fried
Atmos. Chem. Phys., 24, 2207–2237, https://doi.org/10.5194/acp-24-2207-2024, https://doi.org/10.5194/acp-24-2207-2024, 2024
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Formaldehyde observations from satellites can be used to constrain the emissions of volatile organic compounds, but those observations have biases. Using an atmospheric model, aircraft and ground-based remote sensing data, we quantify these biases, propose a correction to the data, and assess the consequence of this correction for the evaluation of emissions.
Haipeng Lin, Louisa K. Emmons, Elizabeth W. Lundgren, Laura Hyesung Yang, Xu Feng, Ruijun Dang, Shixian Zhai, Yunxiao Tang, Makoto M. Kelp, Nadia K. Colombi, Sebastian D. Eastham, Thibaud M. Fritz, and Daniel J. Jacob
EGUsphere, https://doi.org/10.5194/egusphere-2024-470, https://doi.org/10.5194/egusphere-2024-470, 2024
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Tropospheric ozone is a major air pollutant, greenhouse gas, and a major indicator of model skill. Global atmospheric chemistry models show large differences in simulations of tropospheric ozone but isolating sources of differences is complicated by different model environments. By implementing the GEOS-Chem model side-by-side to CAM-chem within a common Earth system model, we identify and evaluate specific differences between the two models and their impacts on key chemical species.
Joël Thanwerdas, Marielle Saunois, Antoine Berchet, Isabelle Pison, and Philippe Bousquet
Atmos. Chem. Phys., 24, 2129–2167, https://doi.org/10.5194/acp-24-2129-2024, https://doi.org/10.5194/acp-24-2129-2024, 2024
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We investigate the causes of the renewed growth of atmospheric methane (CH4) after 2007 using inverse modeling. We use the additional information provided by observations of CH4 isotopic compositions to better differentiate between the emission categories. Accounting for the large uncertainties in source signatures, our results suggest that the post-2007 increase in atmospheric CH4 was caused by similar increases in emissions from (1) fossil fuels and (2) agriculture and waste.
Robin Plauchu, Audrey Fortems-Cheiney, Grégoire Broquet, Isabelle Pison, Antoine Berchet, Elise Potier, Gaëlle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, and Henk Eskes
EGUsphere, https://doi.org/10.5194/egusphere-2024-103, https://doi.org/10.5194/egusphere-2024-103, 2024
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Over 2019–2021, our study used satellite data to assess NOx emissions in France. National budgets decreased due to effective policies, but COVID-19 lockdowns in 2020 didn't uniformly reduce emissions. Focusing on urban areas revealed varied impacts, with challenges like cloud coverage and model errors limiting precision. These findings contribute valuable insights into factors influencing emission assessments, informing future research.
Maarten Krol, Bart van Stratum, Isidora Anglou, and Klaas Folkert Boersma
EGUsphere, https://doi.org/10.5194/egusphere-2023-2519, https://doi.org/10.5194/egusphere-2023-2519, 2024
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This paper presents detailed plume simulations of nitrogen oxides and carbon dioxide that are emitted from four large industrial facilities world-wide. Results from the high-resolution simulations that include atmospheric chemistry are compared to nitrogen-dioxide observations from satellites. We find good performance of the model and show that common assumptions that are used in simplified models need revision. This work is important for the monitoring of emissions using satellite data.
Heather Simon, Christian Hogrefe, Andrew Whitehill, Kristen M. Foley, Jennifer Liljegren, Norm Possiel, Benjamin Wells, Barron H. Henderson, Lukas C. Valin, Gail Tonnesen, K. Wyat Appel, and Shannon Koplitz
Atmos. Chem. Phys., 24, 1855–1871, https://doi.org/10.5194/acp-24-1855-2024, https://doi.org/10.5194/acp-24-1855-2024, 2024
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We assess observed and modeled ozone weekend–weekday differences in the USA from 2002–2019. A subset of urban areas that were NOx-saturated at the beginning of the period transitioned to NOx-limited conditions. Multiple rural areas of California were NOx-limited for the entire period but become less influenced by local day-of-week emission patterns in more recent years. The model produces more NOx-saturated conditions than the observations but captures trends in weekend–weekday ozone patterns.
Rodrigo J. Seguel, Lucas Castillo, Charlie Opazo, Néstor Y. Rojas, Thiago Nogueira, María Cazorla, Mario Gavidia-Calderón, Laura Gallardo, René Garreaud, Tomás Carrasco-Escaff, and Yasin Elshorbany
EGUsphere, https://doi.org/10.5194/egusphere-2024-328, https://doi.org/10.5194/egusphere-2024-328, 2024
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Our research found that surface ozone trends in major South American cities increase or remain steady but show no signs of decreasing. Extra-tropical cities (Santiago and São Paulo), in particular, face the highest risk of ozone exposure. Furthermore, we found that prolonged heat waves and large fires explain many of the most extreme ozone values.
Ryan S. Williams, Michaela I. Hegglin, Patrick Jöckel, Hella Garny, and Keith P. Shine
Atmos. Chem. Phys., 24, 1389–1413, https://doi.org/10.5194/acp-24-1389-2024, https://doi.org/10.5194/acp-24-1389-2024, 2024
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During winter, a brief but abrupt reversal of the mean stratospheric westerly flow (~30 km high) around the Arctic occurs ~6 times a decade. Using a chemistry–climate model, about half of these events are shown to induce large anomalies in Arctic ozone (>25 %) and water vapour (>±25 %) around ~8–12 km altitude for up to 2–3 months, important for weather forecasting. We also calculate a doubling to trebling of the risk in breaches of mid-latitude surface air quality (ozone) standards (~60 ppbv).
Rona L. Thompson, Stephen A. Montzka, Martin K. Vollmer, Jgor Arduini, Molly Crotwell, Paul B. Krummel, Chris Lunder, Jens Mühle, Simon O'Doherty, Ronald G. Prinn, Stefan Reimann, Isaac Vimont, Hsiang Wang, Ray F. Weiss, and Dickon Young
Atmos. Chem. Phys., 24, 1415–1427, https://doi.org/10.5194/acp-24-1415-2024, https://doi.org/10.5194/acp-24-1415-2024, 2024
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The hydroxyl radical determines the atmospheric lifetimes of numerous species including methane. Since OH is very short-lived, it is not possible to directly measure its concentration on scales relevant for understanding its effect on other species. Here, OH is inferred by looking at changes in hydrofluorocarbons (HFCs). We find that OH levels have been fairly stable over our study period (2004 to 2021), suggesting that OH is not the main driver of the recent increase in atmospheric methane.
Zhendong Wu, Alex Vermeulen, Yousuke Sawa, Ute Karstens, Wouter Peters, Remco de Kok, Xin Lan, Yasuyuki Nagai, Akinori Ogi, and Oksana Tarasova
Atmos. Chem. Phys., 24, 1249–1264, https://doi.org/10.5194/acp-24-1249-2024, https://doi.org/10.5194/acp-24-1249-2024, 2024
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This study focuses on exploring the differences in calculating global surface CO2 and its growth rate, considering the impact of analysis methodologies and site selection. Our study reveals that the current global CO2 network has a good capacity to represent global surface CO2 and its growth rate, as well as trends in atmospheric CO2 mass changes. However, small differences exist in different analyses due to the impact of methodology and site selection.
Yang Yang, Yang Zhou, Hailong Wang, Mengyun Li, Huimin Li, Pinya Wang, Xu Yue, Ke Li, Jia Zhu, and Hong Liao
Atmos. Chem. Phys., 24, 1177–1191, https://doi.org/10.5194/acp-24-1177-2024, https://doi.org/10.5194/acp-24-1177-2024, 2024
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This study reveals that extreme ozone pollution over the North China Plain and Yangtze River Delta is due to the chemical production related to hot and dry conditions, and the regional transport explains the ozone pollution over the Sichuan Basin and Pearl River Delta. The frequency of meteorological conditions of the extreme ozone pollution increases from the past to the future. The sustainable scenario is the optimal path to retaining clean air in China in the future.
Victoria A. Flood, Kimberly Strong, Cynthia H. Whaley, Kaley A. Walker, Thomas Blumenstock, James W. Hannigan, Johan Mellqvist, Justus Notholt, Mathias Palm, Amelie N. Röhling, Stephen Arnold, Stephen Beagley, Rong-You Chien, Jesper Christensen, Makoto Deushi, Srdjan Dobricic, Xinyi Dong, Joshua S. Fu, Michael Gauss, Wanmin Gong, Joakim Langner, Kathy S. Law, Louis Marelle, Tatsuo Onishi, Naga Oshima, David A. Plummer, Luca Pozzoli, Jean-Christophe Raut, Manu A. Thomas, Svetlana Tsyro, and Steven Turnock
Atmos. Chem. Phys., 24, 1079–1118, https://doi.org/10.5194/acp-24-1079-2024, https://doi.org/10.5194/acp-24-1079-2024, 2024
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It is important to understand the composition of the Arctic atmosphere and how it is changing. Atmospheric models provide simulations that can inform policy. This study examines simulations of CH4, CO, and O3 by 11 models. Model performance is assessed by comparing results matched in space and time to measurements from five high-latitude ground-based infrared spectrometers. This work finds that models generally underpredict the concentrations of these gases in the Arctic troposphere.
Yao Ge, Sverre Solberg, Mathew Heal, Stefan Reimann, Willem van Caspel, Bryan Hellack, Thérèse Salameh, and David Simpson
EGUsphere, https://doi.org/10.5194/egusphere-2023-3102, https://doi.org/10.5194/egusphere-2023-3102, 2024
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Atmospheric volatile organic compounds (VOC) constitute many species, acting as precursors to ozone and aerosol. Given the uncertainties in VOC emissions, lack of evaluation studies, and recent changes in emissions, this work adapts the EMEP MSC-W to evaluate emission inventories in Europe. We focus on the varying agreement between modelled and measured VOCs across different species, and underscore potential inaccuracies in total and sector-specific emission estimates.
Roger Teoh, Zebediah Engberg, Marc Shapiro, Lynnette Dray, and Marc E. J. Stettler
Atmos. Chem. Phys., 24, 725–744, https://doi.org/10.5194/acp-24-725-2024, https://doi.org/10.5194/acp-24-725-2024, 2024
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Emissions from aircraft contribute to climate change and degrade air quality. We describe an up-to-date 4D emissions inventory of global aviation from 2019 to 2021 based on actual flown trajectories. In 2019, 40.2 million flights collectively travelled 61 billion kilometres using 283 Tg of fuel. Long-haul flights were responsible for 43 % of CO2. The emissions inventory is made available for use in future studies to evaluate the negative externalities arising from global aviation.
Jonas Hachmeister, Oliver Schneising, Michael Buchwitz, John P. Burrows, Justus Notholt, and Matthias Buschmann
Atmos. Chem. Phys., 24, 577–595, https://doi.org/10.5194/acp-24-577-2024, https://doi.org/10.5194/acp-24-577-2024, 2024
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We quantified changes in atmospheric methane concentrations using satellite data and a dynamic linear model approach. We calculated global annual methane increases for the years 2019–2022, which are in good agreement with other sources. For zonal methane growth rates, we identified strong inter-hemispheric differences in 2019 and 2022. For 2022, we could attribute decreases in the global growth rate to the Northern Hemisphere, possibly related to a reduction in anthropogenic emissions.
Glenn-Michael Oomen, Jean-François Müller, Trissevgeni Stavrakou, Isabelle De Smedt, Thomas Blumenstock, Rigel Kivi, Maria Makarova, Mathias Palm, Amelie Röhling, Yao Té, Corinne Vigouroux, Martina M. Friedrich, Udo Frieß, François Hendrick, Alexis Merlaud, Ankie Piters, Andreas Richter, Michel Van Roozendael, and Thomas Wagner
Atmos. Chem. Phys., 24, 449–474, https://doi.org/10.5194/acp-24-449-2024, https://doi.org/10.5194/acp-24-449-2024, 2024
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Natural emissions from vegetation have a profound impact on air quality for their role in the formation of harmful tropospheric ozone and organic aerosols, yet these emissions are highly uncertain. In this study, we quantify emissions of organic gases over Europe using high-quality satellite measurements of formaldehyde. These satellite observations suggest that emissions from vegetation are much higher than predicted by models, especially in southern Europe.
Yongliang She, Jingyi Li, Xiaopu Lyu, Hai Guo, Momei Qin, Xiaodong Xie, Kangjia Gong, Fei Ye, Jianjiong Mao, Lin Huang, and Jianlin Hu
Atmos. Chem. Phys., 24, 219–233, https://doi.org/10.5194/acp-24-219-2024, https://doi.org/10.5194/acp-24-219-2024, 2024
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In this study, we use multi-site volatile organic compound (VOC) measurements to evaluate the CMAQ-model-predicted VOCs and assess the impacts of VOC bias on O3 simulation. Our results demonstrate that current modeling setups and emission inventories are likely to underpredict VOC concentrations, and this underprediction of VOCs contributes to lower O3 predictions in China.
Peiyang Cheng, Arastoo Pour-Biazar, Yuling Wu, Shi Kuang, Richard T. McNider, and William J. Koshak
Atmos. Chem. Phys., 24, 41–63, https://doi.org/10.5194/acp-24-41-2024, https://doi.org/10.5194/acp-24-41-2024, 2024
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Lightning-induced nitrogen monoxide (LNO) emission can be estimated from geostationary satellite observations. The present study uses the LNO emission estimates derived from geostationary satellite observations in an air quality modeling system to investigate the impact of LNO on air quality. Results indicate that significant ozone increase could be due to long-distance chemical transport, lightning activity in the upwind direction, and the mixing of high LNO (or ozone) plumes.
Shuzhuang Feng, Fei Jiang, Tianlu Qian, Nan Wang, Mengwei Jia, Songci Zheng, Jiansong Chen, Fang Ying, and Weimin Ju
EGUsphere, https://doi.org/10.5194/egusphere-2023-2654, https://doi.org/10.5194/egusphere-2023-2654, 2024
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We developed a multi-air pollutant inversion system to estimate non-methane volatile organic compound (NMVOC) emissions using TROPOMI formaldehyde retrievals. We found that the inversion significantly improved formaldehyde simulations and reduced NMVOC emission uncertainties. The optimized NMVOC emissions effectively corrected the overestimation of O3 levels, mainly by decreasing the rate of the RO2 + NO reaction and increasing the rate of the NO2 + OH reaction.
Christian Rödenbeck, Karina E. Adcock, Markus Eritt, Maksym Gachkivskyi, Christoph Gerbig, Samuel Hammer, Armin Jordan, Ralph F. Keeling, Ingeborg Levin, Fabian Maier, Andrew C. Manning, Heiko Moossen, Saqr Munassar, Penelope A. Pickers, Michael Rothe, Yasunori Tohjima, and Sönke Zaehle
Atmos. Chem. Phys., 23, 15767–15782, https://doi.org/10.5194/acp-23-15767-2023, https://doi.org/10.5194/acp-23-15767-2023, 2023
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The carbon dioxide content of the Earth atmosphere is increasing due to human emissions from burning of fossil fuels, causing global climate change. The strength of the fossil-fuel emissions is estimated by inventories based on energy data, but independent validation of these inventories has been recommended by the Intergovernmental Panel on Climate Change. Here we investigate the potential to validate inventories based on measurements of small changes in the atmospheric oxygen content.
Xiaohong Yao and Leiming Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2023-2968, https://doi.org/10.5194/egusphere-2023-2968, 2023
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This study investigates long-term trends of criteria air pollutants, including NO2, CO, SO2, O3 and PM2.5, and (NO2+O3) measured in ten Canadian cities during the last two to three decades and associated driving forces in terms of emission reductions, perturbations from varying weather conditions and large-scale wildfires, and changes in O3 sources and sinks.
Xuewei Hou, Oliver Wild, Bin Zhu, and James Lee
Atmos. Chem. Phys., 23, 15395–15411, https://doi.org/10.5194/acp-23-15395-2023, https://doi.org/10.5194/acp-23-15395-2023, 2023
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In response to the climate crisis, many countries have committed to net zero in a certain future year. The impacts of net-zero scenarios on tropospheric O3 are less well studied and remain unclear. In this study, we quantified the changes of tropospheric O3 budgets, spatiotemporal distributions of future surface O3 in east Asia and regional O3 source contributions for 2060 under a net-zero scenario using the NCAR Community Earth System Model (CESM) and online O3-tagging methods.
Jian Zhu, Shanshan Wang, Chuanqi Gu, Zhiwen Jiang, Sanbao Zhang, Ruibin Xue, Yuhao Yan, and Bin Zhou
EGUsphere, https://doi.org/10.5194/egusphere-2023-2142, https://doi.org/10.5194/egusphere-2023-2142, 2023
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In 2022, Shanghai implemented city-wide static management measures during the high-ozone season in April and May, providing a change to study ozone pollution control. Despite significant emissions reductions, ozone levels increased by 23 %. Statistically, the number of days with higher ozone diurnal variation types increased during the lockdown period. The uneven decline in VOC and NO2 emissions led to heightened photochemical processes, resulting in the observed ozone level rise.
Meghna Soni, Rolf Sander, Lokesh K. Sahu, Domenico Taraborrelli, Pengfei Liu, Ankit Patel, Imran A. Girach, Andrea Pozzer, Sachin S. Gunthe, and Narendra Ojha
Atmos. Chem. Phys., 23, 15165–15180, https://doi.org/10.5194/acp-23-15165-2023, https://doi.org/10.5194/acp-23-15165-2023, 2023
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The study presents the implementation of comprehensive multiphase chlorine chemistry in the box model CAABA/MECCA. Simulations for contrasting urban environments of Asia and Europe highlight the significant impacts of chlorine on atmospheric oxidation capacity and composition. Chemical processes governing the production and loss of chlorine-containing species has been discussed. The updated chemical mechanism will be useful to interpret field measurements and for future air quality studies.
Ling Huang, Jiong Fang, Jiaqiang Liao, Greg Yarwood, Hui Chen, Yangjun Wang, and Li Li
Atmos. Chem. Phys., 23, 14919–14932, https://doi.org/10.5194/acp-23-14919-2023, https://doi.org/10.5194/acp-23-14919-2023, 2023
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Surface ozone concentrations have emerged as a major environmental issue in China. Although control strategies aimed at reducing NOx emissions from conventional combustion sources are widely recognized, soil NOx emissions have received little attention. The impact of soil NO emissions on ground-level ozone concentration is yet to be evaluated. In this study, we estimated the soil NO emissions and evaluated its impact on ozone formation in China.
Ben A. Cala, Scott Archer-Nicholls, James Weber, N. Luke Abraham, Paul T. Griffiths, Lorrie Jacob, Y. Matthew Shin, Laura E. Revell, Matthew Woodhouse, and Alexander T. Archibald
Atmos. Chem. Phys., 23, 14735–14760, https://doi.org/10.5194/acp-23-14735-2023, https://doi.org/10.5194/acp-23-14735-2023, 2023
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Dimethyl sulfide (DMS) is an important trace gas emitted from the ocean recognised as setting the sulfate aerosol background, but its oxidation is complex. As a result representation in chemistry-climate models is greatly simplified. We develop and compare a new mechanism to existing mechanisms via a series of global and box model experiments. Our studies show our updated DMS scheme is a significant improvement but significant variance exists between mechanisms.
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Short summary
We studied changes in air quality in India induced by the COVID-19 lockdown through both surface observations and the CMAQ model. Our results show that emission reductions improved the air quality across India during the lockdown. On average, the levels of PM2.5 and O3 decreased by 28 % and 15 %, indicating positive effects of lockdown measures. We suggest that more stringent and localized emission control strategies should be implemented in India to mitigate air pollutions.
We studied changes in air quality in India induced by the COVID-19 lockdown through both surface...
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