Articles | Volume 18, issue 16
https://doi.org/10.5194/acp-18-11949-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-18-11949-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
21 Aug 2018
Research article |
| 21 Aug 2018
Variations in surface ozone and carbon monoxide in the Kathmandu Valley and surrounding broader regions during SusKat-ABC field campaign: role of local and regional sources
Piyush Bhardwaj
Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, 263002, India
Department of Physics, DSB Campus, Kumaun University, Nainital 263001, India
now at: Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, 263002, India
Maheswar Rupakheti
Institute for Advanced Sustainability Studies (IASS), Potsdam, 14467, Germany
Aurelia Lupascu
Institute for Advanced Sustainability Studies (IASS), Potsdam, 14467, Germany
Andrea Mues
Institute for Advanced Sustainability Studies (IASS), Potsdam, 14467, Germany
Arnico Kumar Panday
International Centre for Integrated Mountain Development (ICIMOD), Kathmandu, 44700, Nepal
Rajesh Kumar
National Center for Atmospheric Research (NCAR) Boulder, 80301, USA
Khadak Singh Mahata
Institute for Advanced Sustainability Studies (IASS), Potsdam, 14467, Germany
Shyam Lal
Physical Research Laboratory (PRL), Ahmedabad, 380009, India
Harish C. Chandola
Department of Physics, DSB Campus, Kumaun University, Nainital 263001, India
Mark G. Lawrence
Institute for Advanced Sustainability Studies (IASS), Potsdam, 14467, Germany
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Gaurav Govardhan, Sachin D. Ghude, Rajesh Kumar, Sumit Sharma, Preeti Gunwani, Chinmay Jena, Prafull Yadav, Shubhangi Ingle, Sreyashi Debnath, Pooja Pawar, Prodip Acharja, Rajmal Jat, Gayatry Kalita, Rupal Ambulkar, Santosh Kulkarni, Akshara Kaginalkar, Vijay K. Soni, Ravi S. Nanjundiah, and Madhavan Rajeevan
Geosci. Model Dev., 17, 2617–2640, https://doi.org/10.5194/gmd-17-2617-2024, https://doi.org/10.5194/gmd-17-2617-2024, 2024
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A newly developed air quality forecasting framework, Decision Support System (DSS), for air quality management in Delhi, India, provides source attribution with numerous emission reduction scenarios besides forecasts. DSS shows that during post-monsoon and winter seasons, Delhi and its neighboring districts contribute to 30 %–40 % each to pollution in Delhi. On average, a 40 % reduction in the emissions in Delhi and the surrounding districts would result in a 24 % reduction in Delhi's pollution.
Matthew S. Johnson, Sajeev Philip, Scott Meech, Rajesh Kumar, Meytar Sorek-Hamer, and Yoichi P. Shiga
EGUsphere, https://doi.org/10.5194/egusphere-2024-583, https://doi.org/10.5194/egusphere-2024-583, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Satellites, such as the Ozone Monitoring Instrument (OMI), retrieve proxy species of ozone (O3) formation (formaldehyde and nitrogen dioxide) and the ratios (FNRs) which can define O3 production sensitivity regimes. Here we investigate trends of OMI FNRs from 2005 to 2021 and they have increased in major cities suggesting a transition from radical- to nitrogen oxide-limited regimes. OMI also observed the impact of reduced emissions during the 2020 COVID-lockdown resulting in increased FNRs.
Connor J. Clayton, Daniel R. Marsh, Steven T. Turnock, Ailish M. Graham, Kirsty J. Pringle, Carly L. Reddington, Rajesh Kumar, and James B. McQuaid
EGUsphere, https://doi.org/10.5194/egusphere-2024-755, https://doi.org/10.5194/egusphere-2024-755, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We demonstrate that strong climate mitigation could lead to vastly improved air quality in Europe, however, only minimal benefits are seen following the current trajectory of climate mitigation. We use a model that allows us to see where the improvements are greatest (Central Europe) and analyse what sectors are most important for achieving these co-benefits (agriculture/power).
Aditya Nalam, Aura Lupascu, Tabish Ansari, and Timothy Butler
EGUsphere, https://doi.org/10.5194/egusphere-2024-432, https://doi.org/10.5194/egusphere-2024-432, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Tropospheric O3 molecules are labelled with the identity of their precursor source in CAM-Chem to quantify the contribution from various emission sources to the tropospheric O3 burden (TOB) and its trends. With an equatorward shift, anthropogenic NOx emissions become significantly more efficient at producing O3 and play a major role in driving TOB trends. This is due to larger convection at the tropics effectively lifting O3 and its precursors to the free troposphere where O3 lifetime is longer.
Yafang Guo, Chayan Roychoudhury, Mohammad Amin Mirrezaei, Rajesh Kumar, Armin Sorooshian, and Avelino F. Arellano
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-234, https://doi.org/10.5194/gmd-2023-234, 2024
Revised manuscript accepted for GMD
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This research focuses on surface ozone (O3) pollution in Arizona, a historically air quality-challenged arid/semi-arid region in the US. The unique characteristics of semi-arid/arid regions, e.g., intense heat, minimal moisture, persistent desert shrubs, play a vital role in comprehending O3 exceedances. Using the WRF-Chem model, we analyzed O3 levels in the pre-monsoon month, revealing the model's skill in capturing diurnal and MDA8 O3 levels.
Leon Kuhn, Steffen Beirle, Vinod Kumar, Sergey Osipov, Andrea Pozzer, Tim Bösch, Rajesh Kumar, and Thomas Wagner
Atmos. Chem. Phys., 24, 185–217, https://doi.org/10.5194/acp-24-185-2024, https://doi.org/10.5194/acp-24-185-2024, 2024
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NO₂ is an important air pollutant. It was observed that the WRF-Chem model shows significant deviations in NO₂ abundance when compared to measurements. We use a 1-month simulation over central Europe to show that these deviations can be mostly resolved by reparameterization of the vertical mixing routine. In order to validate our results, they are compared to in situ, satellite, and MAX-DOAS measurements.
Wenfu Tang, Louisa K. Emmons, Helen M. Worden, Rajesh Kumar, Cenlin He, Benjamin Gaubert, Zhonghua Zheng, Simone Tilmes, Rebecca R. Buchholz, Sara-Eva Martinez-Alonso, Claire Granier, Antonin Soulie, Kathryn McKain, Bruce C. Daube, Jeff Peischl, Chelsea Thompson, and Pieternel Levelt
Geosci. Model Dev., 16, 6001–6028, https://doi.org/10.5194/gmd-16-6001-2023, https://doi.org/10.5194/gmd-16-6001-2023, 2023
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The new MUSICAv0 model enables the study of atmospheric chemistry across all relevant scales. We develop a MUSICAv0 grid for Africa. We evaluate MUSICAv0 with observations and compare it with a previously used model – WRF-Chem. Overall, the performance of MUSICAv0 is comparable to WRF-Chem. Based on model–satellite discrepancies, we find that future field campaigns in an eastern African region (30°E–45°E, 5°S–5°N) could substantially improve the predictive skill of air quality models.
Chupeng Zhang, Shangfei Hai, Yang Gao, Yuhang Wang, Shaoqing Zhang, Lifang Sheng, Bin Zhao, Shuxiao Wang, Jingkun Jiang, Xin Huang, Xiaojing Shen, Junying Sun, Aura Lupascu, Manish Shrivastava, Jerome D. Fast, Wenxuan Cheng, Xiuwen Guo, Ming Chu, Nan Ma, Juan Hong, Qiaoqiao Wang, Xiaohong Yao, and Huiwang Gao
Atmos. Chem. Phys., 23, 10713–10730, https://doi.org/10.5194/acp-23-10713-2023, https://doi.org/10.5194/acp-23-10713-2023, 2023
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New particle formation is an important source of atmospheric particles, exerting critical influences on global climate. Numerical models are vital tools to understanding atmospheric particle evolution, which, however, suffer from large biases in simulating particle numbers. Here we improve the model chemical processes governing particle sizes and compositions. The improved model reveals substantial contributions of newly formed particles to climate through effects on cloud condensation nuclei.
Xiufeng Yin, Dipesh Rupakheti, Guoshuai Zhang, Jiali Luo, Shichang Kang, Benjamin de Foy, Junhua Yang, Zhenming Ji, Zhiyuan Cong, Maheswar Rupakheti, Ping Li, Yuling Hu, and Qianggong Zhang
Atmos. Chem. Phys., 23, 10137–10143, https://doi.org/10.5194/acp-23-10137-2023, https://doi.org/10.5194/acp-23-10137-2023, 2023
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The monthly mean surface ozone concentrations peaked earlier in the south in April and May and later in the north in June and July over the Tibetan Plateau. The migration of monthly surface ozone peaks was coupled with the synchronous movement of tropopause folds and the westerly jet that created conditions conducive to stratospheric ozone intrusion. Stratospheric ozone intrusion significantly contributed to surface ozone across the Tibetan Plateau.
Chandrakala Bharali, Mary Barth, Rajesh Kumar, Sachin D. Ghude, Vinayak Sinha, and Baerbel Sinha
EGUsphere, https://doi.org/10.5194/egusphere-2023-1686, https://doi.org/10.5194/egusphere-2023-1686, 2023
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This study examines the role of atmospheric aerosols in winter fog over the Indo-Gangetic Plains of India using the WRF-Chem model. The increase in RH with aerosol-radiation feedback (ARF) is found to be important for fog formation as it promoted the growth of aerosol and increased aerosol activation in the polluted environment. ARF and aqueous phase chemistry affected the timing of fog formation by ~1–2 hours and the fog intensity by modulating the meteorology and aerosol concentration.
Manu Goudar, Juliëtte C. S. Anema, Rajesh Kumar, Tobias Borsdorff, and Jochen Landgraf
Geosci. Model Dev., 16, 4835–4852, https://doi.org/10.5194/gmd-16-4835-2023, https://doi.org/10.5194/gmd-16-4835-2023, 2023
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A framework was developed to automatically detect plumes and compute emission estimates with cross-sectional flux method (CFM) for biomass burning events in TROPOMI CO datasets using Visible Infrared Imaging Radiometer Suite active fire data. The emissions were more reliable when changing plume height in downwind direction was used instead of constant injection height. The CFM had uncertainty even when the meteorological conditions were accurate; thus there is a need for better inversion models.
Vishnu Thilakan, Dhanyalekshmi Pillai, Jithin Sukumaran, Christoph Gerbig, Haseeb Hakkim, Vinayak Sinha, Yukio Terao, Manish Naja, and Monish Vijay Deshpande
EGUsphere, https://doi.org/10.5194/egusphere-2023-1582, https://doi.org/10.5194/egusphere-2023-1582, 2023
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This study investigates the usability of CO2 mixing ratio observations over India to infer the regional carbon sources and sinks. We demonstrate that a high-resolution modelling system can represent the observed CO2 variations reasonably well by improving the transport and flux variations at a fine scale. Future carbon data assimilation systems can thus be benefitted from these recently available CO2 observations when fine-scale variations are adequately represented in the models.
Matthew S. Johnson, Amir H. Souri, Sajeev Philip, Rajesh Kumar, Aaron Naeger, Jeffrey Geddes, Laura Judd, Scott Janz, Heesung Chong, and John Sullivan
Atmos. Meas. Tech., 16, 2431–2454, https://doi.org/10.5194/amt-16-2431-2023, https://doi.org/10.5194/amt-16-2431-2023, 2023
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Satellites provide vital information for studying the processes controlling ozone formation. Based on the abundance of particular gases in the atmosphere, ozone formation is sensitive to specific human-induced and natural emission sources. However, errors and biases in satellite retrievals hinder this data source’s application for studying ozone formation sensitivity. We conducted a thorough statistical evaluation of two commonly applied satellites for investigating ozone formation sensitivity.
Daniele Visioni, Ben Kravitz, Alan Robock, Simone Tilmes, Jim Haywood, Olivier Boucher, Mark Lawrence, Peter Irvine, Ulrike Niemeier, Lili Xia, Gabriel Chiodo, Chris Lennard, Shingo Watanabe, John C. Moore, and Helene Muri
Atmos. Chem. Phys., 23, 5149–5176, https://doi.org/10.5194/acp-23-5149-2023, https://doi.org/10.5194/acp-23-5149-2023, 2023
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Geoengineering indicates methods aiming to reduce the temperature of the planet by means of reflecting back a part of the incoming radiation before it reaches the surface or allowing more of the planetary radiation to escape into space. It aims to produce modelling experiments that are easy to reproduce and compare with different climate models, in order to understand the potential impacts of these techniques. Here we assess its past successes and failures and talk about its future.
Prajjwal Rawat, Manish Naja, Evan Fishbein, Pradeep K. Thapliyal, Rajesh Kumar, Piyush Bhardwaj, Aditya Jaiswal, Sugriva N. Tiwari, Sethuraman Venkataramani, and Shyam Lal
Atmos. Meas. Tech., 16, 889–909, https://doi.org/10.5194/amt-16-889-2023, https://doi.org/10.5194/amt-16-889-2023, 2023
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Satellite-based ozone observations have gained importance due to their global coverage. However, satellite-retrieved products are indirect and need to be validated, particularly over mountains. Ozonesondes launched from a Himalayan site are used to assess the Atmospheric Infrared Sounder (AIRS) ozone retrieval. AIRS is shown to overestimate ozone in the upper troposphere and lower stratosphere, while the differences from ozonesondes are more minor in the middle troposphere and stratosphere.
Pooja V. Pawar, Sachin D. Ghude, Gaurav Govardhan, Prodip Acharja, Rachana Kulkarni, Rajesh Kumar, Baerbel Sinha, Vinayak Sinha, Chinmay Jena, Preeti Gunwani, Tapan Kumar Adhya, Eiko Nemitz, and Mark A. Sutton
Atmos. Chem. Phys., 23, 41–59, https://doi.org/10.5194/acp-23-41-2023, https://doi.org/10.5194/acp-23-41-2023, 2023
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In this study, for the first time in South Asia we compare simulated ammonia, ammonium, and total ammonia using the WRF-Chem model and MARGA measurements during winter in the Indo-Gangetic Plain region. Since observations show HCl promotes the fraction of high chlorides in Delhi, we added HCl / Cl emissions to the model. We conducted three sensitivity experiments with changes in HCl emissions, and improvements are reported in accurately simulating ammonia, ammonium, and total ammonia.
Felix Kleinert, Lukas H. Leufen, Aurelia Lupascu, Tim Butler, and Martin G. Schultz
Geosci. Model Dev., 15, 8913–8930, https://doi.org/10.5194/gmd-15-8913-2022, https://doi.org/10.5194/gmd-15-8913-2022, 2022
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We examine the effects of spatially aggregated upstream information as input for a deep learning model forecasting near-surface ozone levels. Using aggregated data from one upstream sector (45°) improves the forecast by ~ 10 % for 4 prediction days. Three upstream sectors improve the forecasts by ~ 14 % on the first 2 d only. Our results serve as an orientation for other researchers or environmental agencies focusing on pointwise time-series predictions, for example, due to regulatory purposes.
Johana Romero-Alvarez, Aurelia Lupaşcu, Douglas Lowe, Alba Badia, Scott Archer-Nicholls, Steve Dorling, Claire E. Reeves, and Tim Butler
Atmos. Chem. Phys., 22, 13797–13815, https://doi.org/10.5194/acp-22-13797-2022, https://doi.org/10.5194/acp-22-13797-2022, 2022
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As ozone can be transported across countries, efficient air quality management and regulatory policies rely on the assessment of local ozone production vs. transport. In our study, we investigate the origin of surface ozone in the UK and the contribution of the different source regions to regulatory ozone metrics. It is shown that emission controls would be necessary over western Europe to improve health-related metrics and over larger areas to reduce impacts on ecosystems.
Hossain Mohammed Syedul Hoque, Kengo Sudo, Hitoshi Irie, Alessandro Damiani, Manish Naja, and Al Mashroor Fatmi
Atmos. Chem. Phys., 22, 12559–12589, https://doi.org/10.5194/acp-22-12559-2022, https://doi.org/10.5194/acp-22-12559-2022, 2022
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Nitrogen dioxide (NO2) and formaldehyde (HCHO) are essential trace graces regulating tropospheric ozone chemistry. These trace constituents are measured using an optical passive remote sensing technique. In addition, NO2 and HCHO are simulated with a computer model and evaluated against the observations. Such evaluations are essential to assess model uncertainties and improve their predictability. The results yielded good agreement between the two datasets with some discrepancies.
Aurelia Lupaşcu, Noelia Otero, Andrea Minkos, and Tim Butler
Atmos. Chem. Phys., 22, 11675–11699, https://doi.org/10.5194/acp-22-11675-2022, https://doi.org/10.5194/acp-22-11675-2022, 2022
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Ground-level ozone is an important air pollutant that affects human health, ecosystems, and climate. Ozone is not emitted directly but rather formed in the atmosphere through chemical reactions involving two distinct precursors. Our results provide detailed information about the origin of ozone in Germany during two peak ozone events that took place in 2015 and 2018, thus improving our understanding of ground-level ozone.
Chaman Gul, Shichang Kang, Siva Praveen Puppala, Xiaokang Wu, Cenlin He, Yangyang Xu, Inka Koch, Sher Muhammad, Rajesh Kumar, and Getachew Dubache
Atmos. Chem. Phys., 22, 8725–8737, https://doi.org/10.5194/acp-22-8725-2022, https://doi.org/10.5194/acp-22-8725-2022, 2022
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This work aims to understand concentrations, spatial variability, and potential source regions of light-absorbing impurities (black carbon aerosols, dust particles, and organic carbon) in the surface snow of central and western Himalayan glaciers and their impact on snow albedo and radiative forcing.
Mukesh Rai, Shichang Kang, Junhua Yang, Maheswar Rupakheti, Dipesh Rupakheti, Lekhendra Tripathee, Yuling Hu, and Xintong Chen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-199, https://doi.org/10.5194/acp-2022-199, 2022
Revised manuscript not accepted
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Our study revealed distinctive seasonality with the maximum and minimum aerosol concentrations during the winter and summer seasons respectively. However, interestingly summer high (AOD > 0.8) was observed over South Asia. The highest aerosols are laden over South Asia and East China within 1–2 km, however, aerosol overshooting found up to 10 km due to the deep convection process. Whereas, integrated aerosol transport for OC during spring was found to be 5 times higher than the annual mean.
Shohei Nomura, Manish Naja, M. Kawser Ahmed, Hitoshi Mukai, Yukio Terao, Toshinobu Machida, Motoki Sasakawa, and Prabir K. Patra
Atmos. Chem. Phys., 21, 16427–16452, https://doi.org/10.5194/acp-21-16427-2021, https://doi.org/10.5194/acp-21-16427-2021, 2021
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Long-term measurements of greenhouse gases (GHGs) in India and Bangladesh unveiled specific characteristics in their variations in these regions. Plants including rice cultivated in winter and summer strongly affected seasonal variations and levels in CO2 and CH4. Long-term variability of GHGs showed quite different features in their growth rates from those in Mauna Loa. GHG trends in this region seemed to be hardly affected by El Niño–Southern Oscillation (ENSO).
Stefano Galmarini, Paul Makar, Olivia E. Clifton, Christian Hogrefe, Jesse O. Bash, Roberto Bellasio, Roberto Bianconi, Johannes Bieser, Tim Butler, Jason Ducker, Johannes Flemming, Alma Hodzic, Christopher D. Holmes, Ioannis Kioutsioukis, Richard Kranenburg, Aurelia Lupascu, Juan Luis Perez-Camanyo, Jonathan Pleim, Young-Hee Ryu, Roberto San Jose, Donna Schwede, Sam Silva, and Ralf Wolke
Atmos. Chem. Phys., 21, 15663–15697, https://doi.org/10.5194/acp-21-15663-2021, https://doi.org/10.5194/acp-21-15663-2021, 2021
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This technical note presents the research protocols for phase 4 of the Air Quality Model Evaluation International Initiative (AQMEII4). This initiative has three goals: (i) to define the state of wet and dry deposition in regional models, (ii) to evaluate how dry deposition influences air concentration and flux predictions, and (iii) to identify the causes for prediction differences. The evaluation compares LULC-specific dry deposition and effective conductances and fluxes.
Xinxin Ye, Pargoal Arab, Ravan Ahmadov, Eric James, Georg A. Grell, Bradley Pierce, Aditya Kumar, Paul Makar, Jack Chen, Didier Davignon, Greg R. Carmichael, Gonzalo Ferrada, Jeff McQueen, Jianping Huang, Rajesh Kumar, Louisa Emmons, Farren L. Herron-Thorpe, Mark Parrington, Richard Engelen, Vincent-Henri Peuch, Arlindo da Silva, Amber Soja, Emily Gargulinski, Elizabeth Wiggins, Johnathan W. Hair, Marta Fenn, Taylor Shingler, Shobha Kondragunta, Alexei Lyapustin, Yujie Wang, Brent Holben, David M. Giles, and Pablo E. Saide
Atmos. Chem. Phys., 21, 14427–14469, https://doi.org/10.5194/acp-21-14427-2021, https://doi.org/10.5194/acp-21-14427-2021, 2021
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Wildfire smoke has crucial impacts on air quality, while uncertainties in the numerical forecasts remain significant. We present an evaluation of 12 real-time forecasting systems. Comparison of predicted smoke emissions suggests a large spread in magnitudes, with temporal patterns deviating from satellite detections. The performance for AOD and surface PM2.5 and their discrepancies highlighted the role of accurately represented spatiotemporal emission profiles in improving smoke forecasts.
Fernando Chouza, Thierry Leblanc, Mark Brewer, Patrick Wang, Sabino Piazzolla, Gabriele Pfister, Rajesh Kumar, Carl Drews, Simone Tilmes, Louisa Emmons, and Matthew Johnson
Atmos. Chem. Phys., 21, 6129–6153, https://doi.org/10.5194/acp-21-6129-2021, https://doi.org/10.5194/acp-21-6129-2021, 2021
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The tropospheric ozone lidar at the JPL Table Mountain Facility (TMF) was used to investigate the impact of Los Angeles (LA) Basin pollution transport and stratospheric intrusions in the planetary boundary layer on the San Gabriel Mountains. The results of this study indicate a dominant role of the LA Basin pollution on days when high ozone levels were observed at TMF (March–October period).
Teresa Jorge, Simone Brunamonti, Yann Poltera, Frank G. Wienhold, Bei P. Luo, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, Susanne Körner, Ruud Dirksen, Manish Naja, Suvarna Fadnavis, and Thomas Peter
Atmos. Meas. Tech., 14, 239–268, https://doi.org/10.5194/amt-14-239-2021, https://doi.org/10.5194/amt-14-239-2021, 2021
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Balloon-borne frost point hygrometers are crucial for the monitoring of water vapour in the upper troposphere and lower stratosphere. We found that when traversing a mixed-phase cloud with big supercooled droplets, the intake tube of the instrument collects on its inner surface a high percentage of these droplets. The newly formed ice layer will sublimate at higher levels and contaminate the measurement. The balloon is also a source of contamination, but only at higher levels during the ascent.
Sreeharsha Hanumanthu, Bärbel Vogel, Rolf Müller, Simone Brunamonti, Suvarna Fadnavis, Dan Li, Peter Ölsner, Manish Naja, Bhupendra Bahadur Singh, Kunchala Ravi Kumar, Sunil Sonbawne, Hannu Jauhiainen, Holger Vömel, Beiping Luo, Teresa Jorge, Frank G. Wienhold, Ruud Dirkson, and Thomas Peter
Atmos. Chem. Phys., 20, 14273–14302, https://doi.org/10.5194/acp-20-14273-2020, https://doi.org/10.5194/acp-20-14273-2020, 2020
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During boreal summer, anthropogenic sources yield the Asian Tropopause Aerosol Layer (ATAL), found in Asia between about 13 and 18 km altitude. Balloon-borne measurements of the ATAL conducted in northern India in 2016 show the strong variability of the ATAL. To explain its observed variability, model simulations are performed to deduce the origin of air masses on the Earth's surface, which is important to develop recommendations for regulations of anthropogenic surface emissions of the ATAL.
Tim Butler, Aurelia Lupascu, and Aditya Nalam
Atmos. Chem. Phys., 20, 10707–10731, https://doi.org/10.5194/acp-20-10707-2020, https://doi.org/10.5194/acp-20-10707-2020, 2020
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Ground-level ozone (O3) is not directly emitted; it is formed chemically in the atmosphere. Some ground-level O3 is transported from the stratosphere, but most O3 is produced from reactive precursors that are emitted by both natural and anthropogenic sources. We present the results of a novel source apportionment method for ground-level O3. Our results are consistent with previous work and also provide new insights. In particular, we highlight the roles of methane and international shipping.
Chinmay Jena, Sachin D. Ghude, Rachana Kulkarni, Sreyashi Debnath, Rajesh Kumar, Vijay Kumar Soni, Prodip Acharja, Santosh H. Kulkarni, Manoj Khare, Akshara J. Kaginalkar, Dilip M. Chate, Kaushar Ali, Ravi S. Nanjundiah, and Madhavan N. Rajeevan
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-673, https://doi.org/10.5194/acp-2020-673, 2020
Publication in ACP not foreseen
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Simulations of atmospheric particulate matter (PM2.5) with WRF-Chem model with three different aerosol mechanisms coupled with gas-phase chemical schemes are compared to understand the spatial and temporal variability of PM2.5 over the Indo-Gangetic Plain (IGP) in the winter season. All three chemical schemes underestimate the observed concentrations of major aerosol composition and precursor gases over IGP which in turn affect the optical depth and overall performance of the model for PM2.5.
August Andersson, Elena N. Kirillova, Stefano Decesari, Langley DeWitt, Jimmy Gasore, Katherine E. Potter, Ronald G. Prinn, Maheswar Rupakheti, Jean de Dieu Ndikubwimana, Julius Nkusi, and Bonfils Safari
Atmos. Chem. Phys., 20, 4561–4573, https://doi.org/10.5194/acp-20-4561-2020, https://doi.org/10.5194/acp-20-4561-2020, 2020
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Large-scale biomass burning events seasonally cover sub-Saharan Africa with air particles. In this study, we find that the concentrations of these particles at a remote mountain site in Rwanda may increase by a factor of 10 during such dry biomass burning periods, with strong implications for the regional climate and human health. These results provide quantitative constraints that could contribute to reducing the large uncertainties regarding the environmental impact of these fires.
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.
Md. Robiul Islam, Thilina Jayarathne, Isobel J. Simpson, Benjamin Werden, John Maben, Ashley Gilbert, Puppala S. Praveen, Sagar Adhikari, Arnico K. Panday, Maheswar Rupakheti, Donald R. Blake, Robert J. Yokelson, Peter F. DeCarlo, William C. Keene, and Elizabeth A. Stone
Atmos. Chem. Phys., 20, 2927–2951, https://doi.org/10.5194/acp-20-2927-2020, https://doi.org/10.5194/acp-20-2927-2020, 2020
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The Kathmandu Valley experiences high levels of air pollution. In this study, atmospheric gases and particulate matter were characterized by online and off-line measurements, with an emphasis on understanding their sources. The major sources of particulate matter and trace gases were identified as garbage burning, biomass burning, and vehicles. The majority of secondary organic aerosol was attributed to anthropogenic precursors, while a minority was attributed to biogenic gases.
Aurelia Lupaşcu and Tim Butler
Atmos. Chem. Phys., 19, 14535–14558, https://doi.org/10.5194/acp-19-14535-2019, https://doi.org/10.5194/acp-19-14535-2019, 2019
Pankaj Sadavarte, Maheswar Rupakheti, Prakash Bhave, Kiran Shakya, and Mark Lawrence
Atmos. Chem. Phys., 19, 12953–12973, https://doi.org/10.5194/acp-19-12953-2019, https://doi.org/10.5194/acp-19-12953-2019, 2019
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Emission inventory studies are an important regulatory tool for quantifying the amount of pollutants released in the atmosphere using the fuel consumption and emission rates for different fuels. This study developed an emission inventory over Nepal for 2001–2016 that reveals the changing fuel consumption and subsequently the pollution across different sectors of industrial, transport, agricultural, commercial and residential uses with the use of spatial distribution of anthropogenic activities.
Min Zhong, Eri Saikawa, Alexander Avramov, Chen Chen, Boya Sun, Wenlu Ye, William C. Keene, Robert J. Yokelson, Thilina Jayarathne, Elizabeth A. Stone, Maheswar Rupakheti, and Arnico K. Panday
Atmos. Chem. Phys., 19, 8209–8228, https://doi.org/10.5194/acp-19-8209-2019, https://doi.org/10.5194/acp-19-8209-2019, 2019
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Air pollution is one of the most pressing environmental issues in the Kathmandu Valley, the capital city of Nepal. We estimated emissions from two of the major source types in the valley (vehicles and brick kilns) and found that they have significant impacts on air quality surrounding the valley. Our results highlight the importance of improving local emissions estimates for air quality modeling.
Xin Wan, Shichang Kang, Maheswar Rupakheti, Qianggong Zhang, Lekhendra Tripathee, Junming Guo, Pengfei Chen, Dipesh Rupakheti, Arnico K. Panday, Mark G. Lawrence, Kimitaka Kawamura, and Zhiyuan Cong
Atmos. Chem. Phys., 19, 2725–2747, https://doi.org/10.5194/acp-19-2725-2019, https://doi.org/10.5194/acp-19-2725-2019, 2019
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The sources of primary and secondary aerosols in the Hindu Kush–Himalayan–Tibetan Plateau region are not well known. Organic molecular tracers are useful for aerosol source apportionment. The characterization of molecular tracers were first systemically investigated and the contribution from primary and secondary sources to carbonaceous aerosols was estimated in the Kathmandu Valley. Our results demonstrate that biomass burning contributed a significant fraction to OC in the Kathmandu Valley.
H. Langley DeWitt, Jimmy Gasore, Maheswar Rupakheti, Katherine E. Potter, Ronald G. Prinn, Jean de Dieu Ndikubwimana, Julius Nkusi, and Bonfils Safari
Atmos. Chem. Phys., 19, 2063–2078, https://doi.org/10.5194/acp-19-2063-2019, https://doi.org/10.5194/acp-19-2063-2019, 2019
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Air quality in rapidly developing East Africa is a growing but understudied concern. We analyzed long-term black carbon, carbon monoxide, and ozone measurements from the remote Rwanda Climate Observatory and found that seasonal regional biomass burning raised black carbon levels to above-urban concentrations 6 months out of the year. Additional local pollution could exacerbate this issue. More regional monitoring needs to be done to understand and reduce air pollution in this region.
Ashish Singh, Khadak S. Mahata, Maheswar Rupakheti, Wolfgang Junkermann, Arnico K. Panday, and Mark G. Lawrence
Atmos. Chem. Phys., 19, 245–258, https://doi.org/10.5194/acp-19-245-2019, https://doi.org/10.5194/acp-19-245-2019, 2019
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This paper reports the first airborne measurement campaign in the central Himalayan foothill region, one of the polluted but relatively poorly sampled regions of the world. The measurement campaign quantifies the vertical distribution of aerosols over a polluted mountain valley in the Himalayan foothills and investigates the extent of regional emission transport.
Marianne Tronstad Lund, Gunnar Myhre, Amund Søvde Haslerud, Ragnhild Bieltvedt Skeie, Jan Griesfeller, Stephen Matthew Platt, Rajesh Kumar, Cathrine Lund Myhre, and Michael Schulz
Geosci. Model Dev., 11, 4909–4931, https://doi.org/10.5194/gmd-11-4909-2018, https://doi.org/10.5194/gmd-11-4909-2018, 2018
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Atmospheric aerosols play a key role in the climate system, but their exact impact on the energy balance remains uncertain. Accurate representation of the geographical distribution and properties of aerosols in global models is key to reduce this uncertainty. Here we use a new emission inventory and a range of observations to carefully validate a state-of-the-art model and present an updated estimate of the net direct effect of anthropogenic aerosols since the preindustrial era.
D. S. Shaik, Y. Kant, D. Mitra, H. C. Chandola, and S. Suresh Babu
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., IV-5, 359–366, https://doi.org/10.5194/isprs-annals-IV-5-359-2018, https://doi.org/10.5194/isprs-annals-IV-5-359-2018, 2018
Y. Yarragunta, S. Srivastava, D. Mitra, and H. C. Chandola
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., IV-5, 375–381, https://doi.org/10.5194/isprs-annals-IV-5-375-2018, https://doi.org/10.5194/isprs-annals-IV-5-375-2018, 2018
Simone Brunamonti, Teresa Jorge, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, K. Ravi Kumar, Sunil Sonbawne, Susanne Meier, Deepak Singh, Frank G. Wienhold, Bei Ping Luo, Maxi Boettcher, Yann Poltera, Hannu Jauhiainen, Rijan Kayastha, Jagadishwor Karmacharya, Ruud Dirksen, Manish Naja, Markus Rex, Suvarna Fadnavis, and Thomas Peter
Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, https://doi.org/10.5194/acp-18-15937-2018, 2018
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Based on balloon-borne measurements performed in India and Nepal in 2016–2017, we infer the vertical distributions of water vapor, ozone and aerosols in the atmosphere, from the surface to 30 km altitude. Our measurements show that the atmospheric dynamics of the Asian summer monsoon system over the polluted Indian subcontinent lead to increased concentrations of water vapor and aerosols in the high atmosphere (approximately 14–20 km altitude), which can have an important effect on climate.
J. Douglas Goetz, Michael R. Giordano, Chelsea E. Stockwell, Ted J. Christian, Rashmi Maharjan, Sagar Adhikari, Prakash V. Bhave, Puppala S. Praveen, Arnico K. Panday, Thilina Jayarathne, Elizabeth A. Stone, Robert J. Yokelson, and Peter F. DeCarlo
Atmos. Chem. Phys., 18, 14653–14679, https://doi.org/10.5194/acp-18-14653-2018, https://doi.org/10.5194/acp-18-14653-2018, 2018
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Size distributions and emission factors of submicron aerosol were quantified using online techniques for a variety of common but under-sampled combustion sources in South Asia: wood and dung cooking fires, groundwater pumps, brick kilns, trash burning, and open burning of crop residues. Optical properties (brown carbon light absorption and the absorption Ångström exponent, AAE) of the emissions were also investigated. Contextual comparisons to the literature and other NAMaSTE results were made.
Khadak Singh Mahata, Maheswar Rupakheti, Arnico Kumar Panday, Piyush Bhardwaj, Manish Naja, Ashish Singh, Andrea Mues, Paolo Cristofanelli, Deepak Pudasainee, Paolo Bonasoni, and Mark G. Lawrence
Atmos. Chem. Phys., 18, 14113–14132, https://doi.org/10.5194/acp-18-14113-2018, https://doi.org/10.5194/acp-18-14113-2018, 2018
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This paper presents the first-time simultaneous measurement of CO and O3 at multiple sites in the Kathmandu Valley bottom, its mountain rim and a river outlet, providing their spatial, temporal and seasonal–diurnal variations. Our study reveals that high O3, especially during premonsoon, in observed sites is of high concern for human health and ecosystems in the region. We also estimated CO emission flux to be 2–14 times higher than widely used emission databases (EDGAR HTAP, REAS and INTEX-B).
Tim Butler, Aurelia Lupascu, Jane Coates, and Shuai Zhu
Geosci. Model Dev., 11, 2825–2840, https://doi.org/10.5194/gmd-11-2825-2018, https://doi.org/10.5194/gmd-11-2825-2018, 2018
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This paper describes a method for determining origin of tropospheric ozone simulated in a global chemistry–climate model. This technique can show which precursor compounds were responsible for simulated ozone, and where they were emitted. In this paper we describe our technique, compare and contrast it with several other similar techniques, and use it to calculate the contribution of several different NOx and VOC precursor categories to the tropospheric ozone burden.
Erika von Schneidemesser, Boris Bonn, Tim M. Butler, Christian Ehlers, Holger Gerwig, Hannele Hakola, Heidi Hellén, Andreas Kerschbaumer, Dieter Klemp, Claudia Kofahl, Jürgen Kura, Anja Lüdecke, Rainer Nothard, Axel Pietsch, Jörn Quedenau, Klaus Schäfer, James J. Schauer, Ashish Singh, Ana-Maria Villalobos, Matthias Wiegner, and Mark G. Lawrence
Atmos. Chem. Phys., 18, 8621–8645, https://doi.org/10.5194/acp-18-8621-2018, https://doi.org/10.5194/acp-18-8621-2018, 2018
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This paper provides an overview of the measurements done at an urban background site in Berlin from June-August of 2014. Results show that natural source contributions to ozone and particulate matter (PM) air pollutants are substantial. Large contributions of secondary aerosols formed in the atmosphere to PM10 concentrations were quantified. An analysis of the sources also identified contributions to PM from plant-based sources, vehicles, and a small contribution from wood burning.
Friderike Kuik, Andreas Kerschbaumer, Axel Lauer, Aurelia Lupascu, Erika von Schneidemesser, and Tim M. Butler
Atmos. Chem. Phys., 18, 8203–8225, https://doi.org/10.5194/acp-18-8203-2018, https://doi.org/10.5194/acp-18-8203-2018, 2018
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Modelled NOx concentrations are often underestimated compared to observations, and measurement studies show that reported NOx emissions in urban areas are often too low when the contribution from traffic is largest. This modelling study quantifies the underestimation of traffic NOx emissions in the Berlin–Brandenburg and finds that they are underestimated by ca. 50 % in the core urban area. More research is needed in order to more accurately understand real-world NOx emissions from traffic.
Andrea Mues, Axel Lauer, Aurelia Lupascu, Maheswar Rupakheti, Friderike Kuik, and Mark G. Lawrence
Geosci. Model Dev., 11, 2067–2091, https://doi.org/10.5194/gmd-11-2067-2018, https://doi.org/10.5194/gmd-11-2067-2018, 2018
D. Rupakheti, S. Kang, Z. Cong, M. Rupakheti, L. Tripathee, A. K. Panday, and B. Holben
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-3, 1493–1497, https://doi.org/10.5194/isprs-archives-XLII-3-1493-2018, https://doi.org/10.5194/isprs-archives-XLII-3-1493-2018, 2018
Thilina Jayarathne, Chelsea E. Stockwell, Prakash V. Bhave, Puppala S. Praveen, Chathurika M. Rathnayake, Md. Robiul Islam, Arnico K. Panday, Sagar Adhikari, Rashmi Maharjan, J. Douglas Goetz, Peter F. DeCarlo, Eri Saikawa, Robert J. Yokelson, and Elizabeth A. Stone
Atmos. Chem. Phys., 18, 2259–2286, https://doi.org/10.5194/acp-18-2259-2018, https://doi.org/10.5194/acp-18-2259-2018, 2018
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Emissions of fine particulate matter and its constituents were quantified for a variety of under-sampled combustion sources in South Asia: wood and dung cooking fires, generators, groundwater pumps, brick kilns, trash burning, and open burning of biomasses. Garbage burning and three-stone cooking fires were among the highest emitters, while servicing of motor vehicles significantly reduced PM. These data may be used in source apportionment and to update regional and global emission inventories.
Shradda Dhungel, Bhogendra Kathayat, Khadak Mahata, and Arnico Panday
Atmos. Chem. Phys., 18, 1203–1216, https://doi.org/10.5194/acp-18-1203-2018, https://doi.org/10.5194/acp-18-1203-2018, 2018
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We analyze seasonal and diurnal concentrations of black carbon (BC), ozone, and associated meteorological conditions within a remote trans-Himalayan valley in western Nepal. We observe elevated BC concentrations during non-monsoon seasons, frequent and persistent episodes of higher-than-average concentrations, and net up-valley fluxes throughout the year. The findings provide direct observational evidence of trans-Himalayan valleys serving as vital pollutant transport pathways.
Youhua Tang, Mariusz Pagowski, Tianfeng Chai, Li Pan, Pius Lee, Barry Baker, Rajesh Kumar, Luca Delle Monache, Daniel Tong, and Hyun-Cheol Kim
Geosci. Model Dev., 10, 4743–4758, https://doi.org/10.5194/gmd-10-4743-2017, https://doi.org/10.5194/gmd-10-4743-2017, 2017
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In order to evaluate the data assimilation tools for regional real-time PM2.5 forecasts, we applied a 3D-Var assimilation tool to adjust the aerosol initial condition by assimilating satellite-retrieved aerosol optical depth and surface PM2.5 observations for a regional air quality model, which is compared to another assimilation method, optimal interpolation. We discuss the pros and cons of these two assimilation methods based on the comparison of their 1-month four-cycles-per-day runs.
Astrid M. M. Manders, Peter J. H. Builtjes, Lyana Curier, Hugo A. C. Denier van der Gon, Carlijn Hendriks, Sander Jonkers, Richard Kranenburg, Jeroen J. P. Kuenen, Arjo J. Segers, Renske M. A. Timmermans, Antoon J. H. Visschedijk, Roy J. Wichink Kruit, W. Addo J. van Pul, Ferd J. Sauter, Eric van der Swaluw, Daan P. J. Swart, John Douros, Henk Eskes, Erik van Meijgaard, Bert van Ulft, Peter van Velthoven, Sabine Banzhaf, Andrea C. Mues, Rainer Stern, Guangliang Fu, Sha Lu, Arnold Heemink, Nils van Velzen, and Martijn Schaap
Geosci. Model Dev., 10, 4145–4173, https://doi.org/10.5194/gmd-10-4145-2017, https://doi.org/10.5194/gmd-10-4145-2017, 2017
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The regional-scale air quality model LOTOS–EUROS has been developed by a consortium of Dutch institutes. Recently, version 2.0 of the model was released as an open-source version. Next to a technical description and model evaluation for 2012, this paper presents the model developments in context of the history of air quality modelling and provides an outlook for future directions. Key and innovative applications of LOTOS–EUROS are also highlighted.
Khadak Singh Mahata, Arnico Kumar Panday, Maheswar Rupakheti, Ashish Singh, Manish Naja, and Mark G. Lawrence
Atmos. Chem. Phys., 17, 12573–12596, https://doi.org/10.5194/acp-17-12573-2017, https://doi.org/10.5194/acp-17-12573-2017, 2017
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The paper provides an overview of CH4, CO2, and CO mixing ratios, including diurnal and seasonal variation, and discusses the association of potential sources and meteorology with the observed temporal variation in the Kathmandu Valley. The study will provide an important dataset for a poorly studied region and will be useful for validating estimates from emission inventories, regional models, and satellite observations and assisting in the design of mitigation measures in the region.
Chaeyoon Cho, Sang-Woo Kim, Maheswar Rupakheti, Jin-Soo Park, Arnico Panday, Soon-Chang Yoon, Ji-Hyoung Kim, Hyunjae Kim, Haeun Jeon, Minyoung Sung, Bong Mann Kim, Seungkyu K. Hong, Rokjin J. Park, Dipesh Rupakheti, Khadak Singh Mahata, Puppala Siva Praveen, Mark G. Lawrence, and Brent Holben
Atmos. Chem. Phys., 17, 12617–12632, https://doi.org/10.5194/acp-17-12617-2017, https://doi.org/10.5194/acp-17-12617-2017, 2017
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We investigated the optical and chemical properties and direct radiative effects of aerosols in the Kathmandu Valley. We concluded that the ratio of light-absorbing to scattering aerosols as well as the concentration of light-absorbing aerosols is much higher at Kathmandu than other comparable regions, and it contributes to a great atmospheric absorption efficiency. This study provides unprecedented insights into aerosol optical properties and their radiative forcings in the Kathmandu Valley.
Dipesh Rupakheti, Bhupesh Adhikary, Puppala Siva Praveen, Maheswar Rupakheti, Shichang Kang, Khadak Singh Mahata, Manish Naja, Qianggong Zhang, Arnico Kumar Panday, and Mark G. Lawrence
Atmos. Chem. Phys., 17, 11041–11063, https://doi.org/10.5194/acp-17-11041-2017, https://doi.org/10.5194/acp-17-11041-2017, 2017
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For the first time, atmospheric composition was monitored during pre-monsoon season of 2013 at Lumbini (UNESCO world heritage site as birthplace of the Buddha). PM and O3 frequently exceeded WHO guidelines. Pollution concentration, diurnal characteristics and influence of open burning on air quality in Lumbini were investigated. Potential source regions were also identified. Results show that air pollution at this site is of a great concern, requiring prompt attention for mitigation.
Heiko Bozem, Tim M. Butler, Mark G. Lawrence, Hartwig Harder, Monica Martinez, Dagmar Kubistin, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 17, 10565–10582, https://doi.org/10.5194/acp-17-10565-2017, https://doi.org/10.5194/acp-17-10565-2017, 2017
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We present airborne measurements and model simulations in the tropics and mid-latitudes during GABRIEL and HOOVER, respectively. Based only on in situ data net ozone formation/destruction tendencies (NOPR) are calculated and compared to a 3-D chemistry transport model. The NOPR is positive in the continental boundary layer and the upper troposphere above 6 km. In the marine boundary layer and the middle troposphere ozone destruction prevails. Fresh convection shows strong net ozone formation.
Xin Wan, Shichang Kang, Quanlian Li, Dipesh Rupakheti, Qianggong Zhang, Junming Guo, Pengfei Chen, Lekhendra Tripathee, Maheswar Rupakheti, Arnico K. Panday, Wu Wang, Kimitaka Kawamura, Shaopeng Gao, Guangming Wu, and Zhiyuan Cong
Atmos. Chem. Phys., 17, 8867–8885, https://doi.org/10.5194/acp-17-8867-2017, https://doi.org/10.5194/acp-17-8867-2017, 2017
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Biomass burning (BB) tracers in the aerosols in Lumbini, northern IGP, were studied for the first time. The levoglucosan was the predominant tracer and BB significantly contributed to the air quality in Lumbini. Mixed crop residues and hardwood were main burning materials. BB emissions constituted large fraction of OC, especially during the post-monsoon season. The sources of BB aerosols in Lumbini varies seasonally due to the influence of local emissions and long-range transport.
Andrea Mues, Maheswar Rupakheti, Christoph Münkel, Axel Lauer, Heiko Bozem, Peter Hoor, Tim Butler, and Mark G. Lawrence
Atmos. Chem. Phys., 17, 8157–8176, https://doi.org/10.5194/acp-17-8157-2017, https://doi.org/10.5194/acp-17-8157-2017, 2017
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Ceilometer measurements taken in the Kathmandu Valley, Nepal, were used to study the temporal and spatial evolution of the mixing layer height in the valley. This provides important information on the vertical structure of the atmosphere and can thus also help to understand the mixing of air pollutants (e.g. black carbon) in the valley. The seasonal and diurnal cycles of the mixing layer were found to be highly dependent on meteorology and mainly anticorrelated to black carbon concentrations.
Chinmoy Sarkar, Vinayak Sinha, Baerbel Sinha, Arnico K. Panday, Maheswar Rupakheti, and Mark G. Lawrence
Atmos. Chem. Phys., 17, 8129–8156, https://doi.org/10.5194/acp-17-8129-2017, https://doi.org/10.5194/acp-17-8129-2017, 2017
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This study provides quantitative information regarding the source contributions of the major non-methane volatile organic compound sources in the Kathmandu Valley. Combining high-resolution in situ NMVOC data and model analyses, we show that REAS v2.1 and EDGAR v4.2 emission inventories underestimate the contribution of traffic and do not take the contribution of brick kilns into account. Furthermore, REAS v2.1 overestimates the contribution of residential biofuel use and industries.
Kabindra M. Shakya, Maheswar Rupakheti, Anima Shahi, Rejina Maskey, Bidya Pradhan, Arnico Panday, Siva P. Puppala, Mark Lawrence, and Richard E. Peltier
Atmos. Chem. Phys., 17, 6503–6516, https://doi.org/10.5194/acp-17-6503-2017, https://doi.org/10.5194/acp-17-6503-2017, 2017
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Particulate matter levels were monitored at six major roadway intersections in the Kathmandu Valley during two seasons in 2014. The study documented distinct seasonal (dry season versus wet season) and diel variations in particulate matter levels. This study suggests traffic-related emissions, and soil–dust–construction materials were found to be a major source of particulate matter at these locations.
Sujan Shrestha, Siva Praveen Puppala, Bhupesh Adhikary, Kundan Lal Shrestha, and Arnico K. Panday
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-287, https://doi.org/10.5194/acp-2017-287, 2017
Revised manuscript not accepted
Chelsea E. Stockwell, Ted J. Christian, J. Douglas Goetz, Thilina Jayarathne, Prakash V. Bhave, Puppala S. Praveen, Sagar Adhikari, Rashmi Maharjan, Peter F. DeCarlo, Elizabeth A. Stone, Eri Saikawa, Donald R. Blake, Isobel J. Simpson, Robert J. Yokelson, and Arnico K. Panday
Atmos. Chem. Phys., 16, 11043–11081, https://doi.org/10.5194/acp-16-11043-2016, https://doi.org/10.5194/acp-16-11043-2016, 2016
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We present the first, or rare, field measurements in South Asia of emission factors for up to 80 gases (pollutants, greenhouse gases, and precursors) and black carbon and aerosol optical properties at 405 and 870 nm for many previously under-sampled sources that are important in developing countries such as cooking with dung and wood, garbage and crop residue burning, brick kilns, motorcycles, generators and pumps, etc. Brown carbon contributes significantly to total aerosol absorption.
Boris Bonn, Erika von Schneidemesser, Dorota Andrich, Jörn Quedenau, Holger Gerwig, Anja Lüdecke, Jürgen Kura, Axel Pietsch, Christian Ehlers, Dieter Klemp, Claudia Kofahl, Rainer Nothard, Andreas Kerschbaumer, Wolfgang Junkermann, Rüdiger Grote, Tobias Pohl, Konradin Weber, Birgit Lode, Philipp Schönberger, Galina Churkina, Tim M. Butler, and Mark G. Lawrence
Atmos. Chem. Phys., 16, 7785–7811, https://doi.org/10.5194/acp-16-7785-2016, https://doi.org/10.5194/acp-16-7785-2016, 2016
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The distribution of air pollutants (gases and particles) have been investigated in different environments in Potsdam, Germany. Remarkable variations of the pollutants have been observed for distances of tens of meters by bicycles, vans and aircraft. Vegetated areas caused reductions depending on the pollutants, the vegetation type and dimensions. Our measurements show the pollutants to be of predominantly local origin, resulting in a huge challenge for common models to resolve.
Naveen Chandra, Shyam Lal, S. Venkataramani, Prabir K. Patra, and Varun Sheel
Atmos. Chem. Phys., 16, 6153–6173, https://doi.org/10.5194/acp-16-6153-2016, https://doi.org/10.5194/acp-16-6153-2016, 2016
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About 70 % of man-made CO2 is emitted from the urban areas of the world. Measurements of CO2 and CO are carried out at an urban site, Ahmedabad, India. The observed time series are analysed using a global chemistry-transport model, and correlations between the two species. We have identified the impacts of land ecosystem, man-made emissions and atmospheric transport on CO2 variations. This study is aimed at drawing an effective emission mitigation policy for combating future climate change.
Marje Prank, Mikhail Sofiev, Svetlana Tsyro, Carlijn Hendriks, Valiyaveetil Semeena, Xavier Vazhappilly Francis, Tim Butler, Hugo Denier van der Gon, Rainer Friedrich, Johannes Hendricks, Xin Kong, Mark Lawrence, Mattia Righi, Zissis Samaras, Robert Sausen, Jaakko Kukkonen, and Ranjeet Sokhi
Atmos. Chem. Phys., 16, 6041–6070, https://doi.org/10.5194/acp-16-6041-2016, https://doi.org/10.5194/acp-16-6041-2016, 2016
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Aerosol composition in Europe was simulated by four chemistry transport models and compared to observations to identify the most prominent areas for model improvement. Notable differences were found between the models' predictions, attributable to different treatment or omission of aerosol sources and processes. All models underestimated the observed concentrations by 10–60 %, mostly due to under-predicting the carbonaceous and mineral particles and omitting the aerosol-bound water.
Chinmoy Sarkar, Vinayak Sinha, Vinod Kumar, Maheswar Rupakheti, Arnico Panday, Khadak S. Mahata, Dipesh Rupakheti, Bhogendra Kathayat, and Mark G. Lawrence
Atmos. Chem. Phys., 16, 3979–4003, https://doi.org/10.5194/acp-16-3979-2016, https://doi.org/10.5194/acp-16-3979-2016, 2016
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First deployment of PTR-TOF-MS in South Asia. High acetaldehyde and biogenic isoprene concentrations detected even in winter in the Kathmandu Valley. Isocyanic acid, formamide, acetamide, naphthalene and nitromethane were detected for the first time in South Asian air. Oxygenated VOCs and isoprene-dominated OH reactivity and ozone production potentials (> 68 % OPP). Regulation of emissions from biomass co-fired brick kilns' by cleaner technology would improve air quality of the valley.
Peng Fei Chen, Chao Liu Li, Shi Chang Kang, Maheswar Rupakheti, Arnico K. Panday, Fang Ping Yan, Quan Lian Li, Qiang Gong Zhang, Jun Ming Guo, Dipesh Rupakheti, and Wei Luo
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-71, https://doi.org/10.5194/acp-2016-71, 2016
Revised manuscript not accepted
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PAHs were measured at six sites along two south-north transects across the central Himalayas. The annual average PAHs and their dry deposition fluxes decreased noticeably from the south to north sides, however, a similar compostion pattern was found at three remote sites, suggesting the northern slope of the Himalayas may be affected by anthropogenic emissions form Indo-Gangetic Plain. PAHs showed a clear seasonal variation at Nepal and they were mainly form biomass and fossil combustion .
Som Sharma, Rajesh Vaishnav, Munn V. Shukla, Prashant Kumar, Prateek Kumar, Pradeep K. Thapliyal, Shyam Lal, and Yashwant B. Acharya
Atmos. Meas. Tech., 9, 711–719, https://doi.org/10.5194/amt-9-711-2016, https://doi.org/10.5194/amt-9-711-2016, 2016
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Cloud base height observations from Ceilometer CL31 were extensively studied during May 2013 to January 2015 over Ahmedabad (23.03°N, 72.54°E), India. Results indicate that the ceilometer is an excellent instrument to precisely detect low- and mid-level clouds, and that the MODIS satellite provides accurate retrieval of high-level clouds over this region.
E. W. Butt, A. Rap, A. Schmidt, C. E. Scott, K. J. Pringle, C. L. Reddington, N. A. D. Richards, M. T. Woodhouse, J. Ramirez-Villegas, H. Yang, V. Vakkari, E. A. Stone, M. Rupakheti, P. S. Praveen, P. G. van Zyl, J. P. Beukes, M. Josipovic, E. J. S. Mitchell, S. M. Sallu, P. M. Forster, and D. V. Spracklen
Atmos. Chem. Phys., 16, 873–905, https://doi.org/10.5194/acp-16-873-2016, https://doi.org/10.5194/acp-16-873-2016, 2016
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We estimate the impact of residential emissions (cooking and heating) on atmospheric aerosol, human health, and climate. We find large contributions to annual mean ambient PM2.5 in residential sources regions resulting in significant but uncertain global premature mortality when key uncertainties in emission flux are considered. We show that residential emissions exert an uncertain global radiative effect and suggest more work is needed to characterise residential emissions climate importance.
K. Niranjan Kumar, D. V. Phanikumar, T. B. M. J. Ouarda, M. Rajeevan, M. Naja, and K. K. Shukla
Ann. Geophys., 34, 123–132, https://doi.org/10.5194/angeo-34-123-2016, https://doi.org/10.5194/angeo-34-123-2016, 2016
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The link between upper-tropospheric planetary-scale Rossby waves and surface meteorological parameters is examined. The propagating Rossby waves along with undulations in the subtropical jet create convergence and divergence regions in the mid-troposphere. The surface relative humidity, wind speeds, and temperature are synchronized with the phase of the propagating Rossby waves. The present study finds important implications for medium-range forecasting through Rossby wave propagation.
D. Putero, P. Cristofanelli, A. Marinoni, B. Adhikary, R. Duchi, S. D. Shrestha, G. P. Verza, T. C. Landi, F. Calzolari, M. Busetto, G. Agrillo, F. Biancofiore, P. Di Carlo, A. K. Panday, M. Rupakheti, and P. Bonasoni
Atmos. Chem. Phys., 15, 13957–13971, https://doi.org/10.5194/acp-15-13957-2015, https://doi.org/10.5194/acp-15-13957-2015, 2015
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The aim of this paper is to present a full-year analysis of simultaneous measurements of ozone, black carbon, and aerosol number concentration at Paknajol, in the Kathmandu Valley, one of the global “hot spots” in terms of air pollution. Results indicate persisting poor air quality conditions throughout the measurement period, and suggest that the pollutants' variability is mainly driven by local pollution source activity, local- and large-scale dynamics, photochemistry, and vegetation fires.
A. Lupascu, R. Easter, R. Zaveri, M. Shrivastava, M. Pekour, J. Tomlinson, Q. Yang, H. Matsui, A. Hodzic, Q. Zhang, and J. D. Fast
Atmos. Chem. Phys., 15, 12283–12313, https://doi.org/10.5194/acp-15-12283-2015, https://doi.org/10.5194/acp-15-12283-2015, 2015
B. Kravitz, A. Robock, S. Tilmes, O. Boucher, J. M. English, P. J. Irvine, A. Jones, M. G. Lawrence, M. MacCracken, H. Muri, J. C. Moore, U. Niemeier, S. J. Phipps, J. Sillmann, T. Storelvmo, H. Wang, and S. Watanabe
Geosci. Model Dev., 8, 3379–3392, https://doi.org/10.5194/gmd-8-3379-2015, https://doi.org/10.5194/gmd-8-3379-2015, 2015
M. Beekmann, A. S. H. Prévôt, F. Drewnick, J. Sciare, S. N. Pandis, H. A. C. Denier van der Gon, M. Crippa, F. Freutel, L. Poulain, V. Ghersi, E. Rodriguez, S. Beirle, P. Zotter, S.-L. von der Weiden-Reinmüller, M. Bressi, C. Fountoukis, H. Petetin, S. Szidat, J. Schneider, A. Rosso, I. El Haddad, A. Megaritis, Q. J. Zhang, V. Michoud, J. G. Slowik, S. Moukhtar, P. Kolmonen, A. Stohl, S. Eckhardt, A. Borbon, V. Gros, N. Marchand, J. L. Jaffrezo, A. Schwarzenboeck, A. Colomb, A. Wiedensohler, S. Borrmann, M. Lawrence, A. Baklanov, and U. Baltensperger
Atmos. Chem. Phys., 15, 9577–9591, https://doi.org/10.5194/acp-15-9577-2015, https://doi.org/10.5194/acp-15-9577-2015, 2015
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A detailed characterization of air quality in the Paris (France) agglomeration, a megacity, during two summer and winter intensive campaigns and from additional 1-year observations, revealed that about 70% of the fine particulate matter (PM) at urban background is transported into the megacity from upwind regions. Unexpectedly, a major part of organic PM is of modern origin (woodburning and cooking activities, secondary formation from biogenic VOC).
Z. L. Lüthi, B. Škerlak, S.-W. Kim, A. Lauer, A. Mues, M. Rupakheti, and S. Kang
Atmos. Chem. Phys., 15, 6007–6021, https://doi.org/10.5194/acp-15-6007-2015, https://doi.org/10.5194/acp-15-6007-2015, 2015
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The Himalayas and the Tibetan Plateau region (HTP) is regularly exposed to polluted air masses that might influence glaciers as well as climate on regional to global scales. We found that atmospheric brown clouds from South Asia reach the HTP by crossing the Himalayas not only through the major north--south river valleys but rather over large areas by being lifted and advected at mid-troposheric levels. The transport is enabled by a combination of synoptic and local meteorological settings.
R. Kumar, M. C. Barth, V. S. Nair, G. G. Pfister, S. Suresh Babu, S. K. Satheesh, K. Krishna Moorthy, G. R. Carmichael, Z. Lu, and D. G. Streets
Atmos. Chem. Phys., 15, 5415–5428, https://doi.org/10.5194/acp-15-5415-2015, https://doi.org/10.5194/acp-15-5415-2015, 2015
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We examine differences in the surface BC between the Bay of Bengal (BoB) and the Arabian Sea (AS) and identify dominant sources of BC in South Asia during ICARB. Anthropogenic emissions were the main source of BC during ICARB and had about 5 times stronger influence on the BoB compared to the AS. Regional-scale transport contributes up to 25% of BC mass concentrations in western and eastern India, suggesting that surface BC mass concentrations cannot be linked directly to the local emissions.
L. Drinovec, G. Močnik, P. Zotter, A. S. H. Prévôt, C. Ruckstuhl, E. Coz, M. Rupakheti, J. Sciare, T. Müller, A. Wiedensohler, and A. D. A. Hansen
Atmos. Meas. Tech., 8, 1965–1979, https://doi.org/10.5194/amt-8-1965-2015, https://doi.org/10.5194/amt-8-1965-2015, 2015
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We present a new real-time algorithm for compensation of the filter-loading effect in filter photometers, based on a two parallel spot measurement of optical absorption. This algorithm has been incorporated into the new Aethalometer AE33. Intercomparison studies show excellent reproducibility of the AE33 measurements and very good agreement with post-processed data obtained using earlier aethalometer models and other filter-based absorption photometers.
R. Kumar, M. C. Barth, S. Madronich, M. Naja, G. R. Carmichael, G. G. Pfister, C. Knote, G. P. Brasseur, N. Ojha, and T. Sarangi
Atmos. Chem. Phys., 14, 6813–6834, https://doi.org/10.5194/acp-14-6813-2014, https://doi.org/10.5194/acp-14-6813-2014, 2014
R. Kumar, M. C. Barth, G. G. Pfister, M. Naja, and G. P. Brasseur
Atmos. Chem. Phys., 14, 2431–2446, https://doi.org/10.5194/acp-14-2431-2014, https://doi.org/10.5194/acp-14-2431-2014, 2014
D. V. Phanikumar, K. Niranjan Kumar, K. K. Shukla, H. Joshi, M. Venkat Ratnam, M. Naja, and K. Reddy
Ann. Geophys., 32, 175–180, https://doi.org/10.5194/angeo-32-175-2014, https://doi.org/10.5194/angeo-32-175-2014, 2014
C. Liu, S. Beirle, T. Butler, P. Hoor, C. Frankenberg, P. Jöckel, M. Penning de Vries, U. Platt, A. Pozzer, M. G. Lawrence, J. Lelieveld, H. Tost, and T. Wagner
Atmos. Chem. Phys., 14, 1717–1732, https://doi.org/10.5194/acp-14-1717-2014, https://doi.org/10.5194/acp-14-1717-2014, 2014
A. Mues, J. Kuenen, C. Hendriks, A. Manders, A. Segers, Y. Scholz, C. Hueglin, P. Builtjes, and M. Schaap
Atmos. Chem. Phys., 14, 939–955, https://doi.org/10.5194/acp-14-939-2014, https://doi.org/10.5194/acp-14-939-2014, 2014
Z. S. Stock, M. R. Russo, T. M. Butler, A. T. Archibald, M. G. Lawrence, P. J. Telford, N. L. Abraham, and J. A. Pyle
Atmos. Chem. Phys., 13, 12215–12231, https://doi.org/10.5194/acp-13-12215-2013, https://doi.org/10.5194/acp-13-12215-2013, 2013
S. M. Burrows, P. J. Rayner, T. Butler, and M. G. Lawrence
Atmos. Chem. Phys., 13, 5473–5488, https://doi.org/10.5194/acp-13-5473-2013, https://doi.org/10.5194/acp-13-5473-2013, 2013
D. Kunkel, H. Tost, and M. G. Lawrence
Atmos. Chem. Phys., 13, 4203–4222, https://doi.org/10.5194/acp-13-4203-2013, https://doi.org/10.5194/acp-13-4203-2013, 2013
J. Lelieveld, M. G. Lawrence, and D. Kunkel
Atmos. Chem. Phys., 13, 31–34, https://doi.org/10.5194/acp-13-31-2013, https://doi.org/10.5194/acp-13-31-2013, 2013
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Contribution of cooking emissions to the urban volatile organic compounds in Las Vegas, NV
Reanalysis of NOAA H2 observations: implications for the H2 budget
A large role of missing volatile organic compound reactivity from anthropogenic emissions in ozone pollution regulation
Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)
Production of oxygenated volatile organic compounds from the ozonolysis of coastal seawater
Comment on “Transport of substantial stratospheric ozone to the surface by a dying typhoon and shallow convection” by Chen et al. (2022)
Observations of cyanogen bromide (BrCN) in the global troposphere and their relation to polar surface O3 destruction
Individual coal mine methane emissions constrained by eddy covariance measurements: low bias and missing sources
Measurement report: Observations of ground-level ozone concentration gradients perpendicular to the Lake Ontario shoreline
Measurement report: The Palau Atmospheric Observatory and its ozonesonde record – continuous monitoring of tropospheric composition and dynamics in the tropical western Pacific
Quantifying SO2 oxidation pathways to atmospheric sulfate using stable sulfur and oxygen isotopes: laboratory simulation and field observation
Influences of downward transport and photochemistry on surface ozone over East Antarctica during austral summer: in situ observations and model simulations
Iodine oxoacids and their roles in sub-3 nm particle growth in polluted urban environments
Intensive photochemical oxidation in the marine atmosphere: evidence from direct radical measurements
Diurnal variations in oxygen and nitrogen isotopes of atmospheric nitrogen dioxide and nitrate: implications for tracing NOx oxidation pathways and emission sources
Measurement report: Method for evaluating CO2 emissions from a cement plant using atmospheric δ(O2 ∕ N2) and CO2 measurements and its implication for future detection of CO2 capture signals
Aircraft-based mass balance estimate of methane emissions from offshore gas facilities in the southern North Sea
Parameterizations of US wildfire and prescribed fire emission ratios and emission factors based on FIREX-AQ aircraft measurements
Measurement report: Atmospheric nitrate radical chemistry in the South China Sea influenced by the urban outflow of the Pearl River Delta
The interhemispheric gradient of SF6 in the upper troposphere
Weather regimes and the related atmospheric composition at a Pyrenean observatory characterized by hierarchical clustering of a 5-year data set
Tropospheric bromine monoxide vertical profiles retrieved across the Alaskan Arctic in springtime
Source apportionment of methane emissions from the Upper Silesian Coal Basin using isotopic signatures
Measurement report: Exchange fluxes of HONO over agricultural fields in the North China Plain
HONO chemistry at a suburban site during the EXPLORE-YRD campaign in 2018: formation mechanisms and impacts on O3 production
Evaluation of modelled climatologies of O3, CO, water vapour and NOy in the upper troposphere–lower stratosphere using regular in situ observations by passenger aircraft
Photochemical ageing of aerosols contributes significantly to the production of atmospheric formic acid
Nitrous acid budgets in the coastal atmosphere: potential daytime marine sources
Sources of organic gases and aerosol particles and their roles in nighttime particle growth at a rural forested site in southwest Germany
Undetected biogenic volatile organic compounds from Norway spruce drive total ozone reactivity measurements
Quantification of fossil fuel CO2 from combined CO, δ13CO2 and Δ14CO2 observations
Radical chemistry and ozone production at a UK coastal receptor site
Sources and long-term variability of carbon monoxide at Mount Kenya and in Nairobi
Shipping and algae emissions have a major impact on ambient air mixing ratios of NMHCs and methanethiol on Utö island in the Baltic Sea
Opinion: Strengthening Research in the Global South: Atmospheric Science Opportunities in South America and Africa
Measurement report: Airborne measurements of NOx fluxes over Los Angeles during the RECAP-CA 2021 campaign
Influence of anthropogenic emissions on the composition of highly oxygenated organic molecules in Helsinki: a street canyon and urban background station comparison
Changes in surface ozone in South Korea on diurnal to decadal timescales for the period of 2001–2021
Characterization of the nitrogen stable isotope composition (δ15N) of ship-emitted NOx
Volatile organic compound fluxes in the agricultural San Joaquin Valley – spatial distribution, source attribution, and inventory comparison
Exploring the amplified role of HCHO in the formation of HMS and O3 during the co-occurring PM2.5 and O3 pollution in a coastal city of southeast China
High potential for CH4 emission mitigation from oil infrastructure in one of EU's major production regions
Measurement report: Source apportionment and environmental impacts of volatile organic compounds (VOCs) in Lhasa, a highland city in China
OH, HO2, and RO2 radical chemistry in a rural forest environment: measurements, model comparisons, and evidence of a missing radical sink
The atmospheric fate of 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH): spatial patterns, seasonal variability, and deposition to Canadian coastal regions
A single-point modeling approach for the intercomparison and evaluation of ozone dry deposition across chemical transport models (Activity 2 of AQMEII4)
Direct observations of NOx emissions over the San Joaquin Valley using airborne flux measurements during RECAP-CA 2021 field campaign
Surface snow bromide and nitrate at Eureka, Canada in early spring and implications for polar boundary layer chemistry
Trends and seasonal variability in ammonia across major biomes in western and central Africa inferred from long-term series of ground-based and satellite measurements
A rise in HFC-23 emissions from eastern Asia since 2015
Matthew M. Coggon, Chelsea E. Stockwell, Lu Xu, Jeff Peischl, Jessica B. Gilman, Aaron Lamplugh, Henry J. Bowman, Kenneth Aikin, Colin Harkins, Qindan Zhu, Rebecca H. Schwantes, Jian He, Meng Li, Karl Seltzer, Brian McDonald, and Carsten Warneke
Atmos. Chem. Phys., 24, 4289–4304, https://doi.org/10.5194/acp-24-4289-2024, https://doi.org/10.5194/acp-24-4289-2024, 2024
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Residential and commercial cooking emits pollutants that degrade air quality. Here, ambient observations show that cooking is an important contributor to anthropogenic volatile organic compounds (VOCs) emitted in Las Vegas, NV. These emissions are not fully presented in air quality models, and more work may be needed to quantify emissions from important sources, such as commercial restaurants.
Fabien Paulot, Gabrielle Pétron, Andrew M. Crotwell, and Matteo B. Bertagni
Atmos. Chem. Phys., 24, 4217–4229, https://doi.org/10.5194/acp-24-4217-2024, https://doi.org/10.5194/acp-24-4217-2024, 2024
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New data from the National Oceanic and Atmospheric Administration show that hydrogen (H2) concentrations increased from 2010 to 2019, which is consistent with the simulated increase in H2 photochemical production (mainly from methane). But this cannot be reconciled with the expected decrease (increase) in H2 anthropogenic emissions (soil deposition) in the same period. This shows gaps in our knowledge of the H2 biogeochemical cycle that must be resolved to quantify the impact of higher H2 usage.
Wenjie Wang, Bin Yuan, Hang Su, Yafang Cheng, Jipeng Qi, Sihang Wang, Wei Song, Xinming Wang, Chaoyang Xue, Chaoqun Ma, Fengxia Bao, Hongli Wang, Shengrong Lou, and Min Shao
Atmos. Chem. Phys., 24, 4017–4027, https://doi.org/10.5194/acp-24-4017-2024, https://doi.org/10.5194/acp-24-4017-2024, 2024
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This study investigates the important role of unmeasured volatile organic compounds (VOCs) in ozone formation. Based on results in a megacity of China, we show that unmeasured VOCs can contribute significantly to ozone fomation and also influence the determination of ozone control strategy. Our results show that these unmeasured VOCs are mainly from human sources.
Romain Salignat, Matti Rissanen, Siddharth Iyer, Jean-Luc Baray, Pierre Tulet, Jean-Marc Metzger, Jérôme Brioude, Karine Sellegri, and Clémence Rose
Atmos. Chem. Phys., 24, 3785–3812, https://doi.org/10.5194/acp-24-3785-2024, https://doi.org/10.5194/acp-24-3785-2024, 2024
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Using mass spectrometry data collected at the Maïdo Observatory (2160 m a.s.l., Réunion), we provide the first detailed analysis of molecular cluster chemical composition specifically in the marine free troposphere. The abundance of the identified species is related both to in situ meteorological parameters and air mass history, which also provide insight into their origin. Our work makes an important contribution to documenting the chemistry and physics of the marine free troposphere.
Delaney B. Kilgour, Gordon A. Novak, Megan S. Claflin, Brian M. Lerner, and Timothy H. Bertram
Atmos. Chem. Phys., 24, 3729–3742, https://doi.org/10.5194/acp-24-3729-2024, https://doi.org/10.5194/acp-24-3729-2024, 2024
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Laboratory experiments with seawater mimics suggest ozone deposition to the surface ocean can be a source of reactive carbon to the marine atmosphere. We conduct both field and laboratory measurements to assess abiotic VOC composition and yields from ozonolysis of real surface seawater. We show that C5–C11 aldehydes contribute to the observed VOC emission flux. We estimate that VOCs generated by the ozonolysis of surface seawater are competitive with biological VOC production and emission.
Xiangdong Zheng, Wen Yang, Yuting Sun, Chunmei Geng, Yingying Liu, and Xiaobin Xu
Atmos. Chem. Phys., 24, 3759–3768, https://doi.org/10.5194/acp-24-3759-2024, https://doi.org/10.5194/acp-24-3759-2024, 2024
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Chen et al. (2022) attributed the nocturnal ozone enhancement (NOE) during the night of 31 July 2021 in the North China Plain (NCP) to "the direct stratospheric intrusion to reach the surface". We analyzed in situ data from the NCP. Our results do not suggest that there was a significant impact from the stratosphere on surface ozone during the NOE. We argue that the NOE was not caused by stratospheric intrusion but originated from fresh photochemical production in the lower troposphere.
James M. Roberts, Siyuan Wang, Patrick R. Veres, J. Andrew Neuman, Michael A. Robinson, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Chelsea R. Thompson, Hannah M. Allen, John D. Crounse, Paul O. Wennberg, Samuel R. Hall, Kirk Ullmann, Simone Meinardi, Isobel J. Simpson, and Donald Blake
Atmos. Chem. Phys., 24, 3421–3443, https://doi.org/10.5194/acp-24-3421-2024, https://doi.org/10.5194/acp-24-3421-2024, 2024
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We measured cyanogen bromide (BrCN) in the troposphere for the first time. BrCN is a product of the same active bromine chemistry that destroys ozone and removes mercury in polar surface environments and is a previously unrecognized sink for active Br compounds. BrCN has an apparent lifetime against heterogeneous loss in the range 1–10 d, so it serves as a cumulative marker of Br-radical chemistry. Accounting for BrCN chemistry is an important part of understanding polar Br cycling.
Kai Qin, Wei Hu, Qin He, Fan Lu, and Jason Blake Cohen
Atmos. Chem. Phys., 24, 3009–3028, https://doi.org/10.5194/acp-24-3009-2024, https://doi.org/10.5194/acp-24-3009-2024, 2024
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We compute CH4 emissions and uncertainty on a mine-by-mine basis, including underground, overground, and abandoned mines. Mine-by-mine gas and flux data and 30 min observations from a flux tower located next to a mine shaft are integrated. The observed variability and bias correction are propagated over the emissions dataset, demonstrating that daily observations may not cover the range of variability. Comparisons show both an emissions magnitude and spatial mismatch with current inventories.
Yao Yan Huang and D. James Donaldson
Atmos. Chem. Phys., 24, 2387–2398, https://doi.org/10.5194/acp-24-2387-2024, https://doi.org/10.5194/acp-24-2387-2024, 2024
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Ground-level ozone interacts at the lake–land boundary; this is important to our understanding and modelling of atmospheric chemistry and air pollution in the lower atmosphere. We show that a steep ozone gradient occurs year-round moving inland up to 1 km from the lake and that this gradient is influenced by seasonal factors on the local land environment, where more rural areas are more greatly affected seasonally.
Katrin Müller, Jordis S. Tradowsky, Peter von der Gathen, Christoph Ritter, Sharon Patris, Justus Notholt, and Markus Rex
Atmos. Chem. Phys., 24, 2169–2193, https://doi.org/10.5194/acp-24-2169-2024, https://doi.org/10.5194/acp-24-2169-2024, 2024
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The Palau Atmospheric Observatory is introduced as an ideal site to detect changes in atmospheric composition and dynamics above the remote tropical western Pacific. We focus on the ozone sounding program from 2016–2021, including El Niño 2016. The year-round high convective activity is reflected in dominant low tropospheric ozone and high relative humidity. Their seasonal distributions are unique compared to other tropical sites and are modulated by the Intertropical Convergence Zone.
Ziyan Guo, Keding Lu, Pengxiang Qiu, Mingyi Xu, and Zhaobing Guo
Atmos. Chem. Phys., 24, 2195–2205, https://doi.org/10.5194/acp-24-2195-2024, https://doi.org/10.5194/acp-24-2195-2024, 2024
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The formation of secondary sulfate needs to be further explored. In this work, we simultaneously measured sulfur and oxygen isotopic compositions to gain an increased understanding of specific sulfate formation processes. The results indicated that secondary sulfate was mainly ascribed to SO2 homogeneous oxidation by OH radicals and heterogeneous oxidation by H2O2 and Fe3+ / O2. This study is favourable for deeply investigating the sulfur cycle in the atmosphere.
Imran A. Girach, Narendra Ojha, Prabha R. Nair, Kandula V. Subrahmanyam, Neelakantan Koushik, Mohammed M. Nazeer, Nadimpally Kiran Kumar, Surendran Nair Suresh Babu, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 24, 1979–1995, https://doi.org/10.5194/acp-24-1979-2024, https://doi.org/10.5194/acp-24-1979-2024, 2024
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We investigate surface ozone variability in East Antarctica based on measurements and EMAC global model simulations during austral summer. Nearly half of the surface ozone is found to be of stratospheric origin. The east coast of Antarctica acts as a stronger sink of ozone than surrounding regions. Photochemical loss of ozone is counterbalanced by downward transport of ozone. The study highlights the intertwined role of chemistry and dynamics in governing ozone variations over East Antarctica.
Ying Zhang, Duzitian Li, Xu-Cheng He, Wei Nie, Chenjuan Deng, Runlong Cai, Yuliang Liu, Yishuo Guo, Chong Liu, Yiran Li, Liangduo Chen, Yuanyuan Li, Chenjie Hua, Tingyu Liu, Zongcheng Wang, Jiali Xie, Lei Wang, Tuukka Petäjä, Federico Bianchi, Ximeng Qi, Xuguang Chi, Pauli Paasonen, Yongchun Liu, Chao Yan, Jingkun Jiang, Aijun Ding, and Markku Kulmala
Atmos. Chem. Phys., 24, 1873–1893, https://doi.org/10.5194/acp-24-1873-2024, https://doi.org/10.5194/acp-24-1873-2024, 2024
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This study conducts a long-term observation of gaseous iodine oxoacids in two Chinese megacities, revealing their ubiquitous presence with peak concentrations (up to 0.1 pptv) in summer. Our analysis suggests a mix of terrestrial and marine sources for iodine. Additionally, iodic acid is identified as a notable contributor to sub-3 nm particle growth and particle survival probability.
Guoxian Zhang, Renzhi Hu, Pinhua Xie, Changjin Hu, Xiaoyan Liu, Liujun Zhong, Haotian Cai, Bo Zhu, Shiyong Xia, Xiaofeng Huang, Xin Li, and Wenqing Liu
Atmos. Chem. Phys., 24, 1825–1839, https://doi.org/10.5194/acp-24-1825-2024, https://doi.org/10.5194/acp-24-1825-2024, 2024
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Comprehensive observation of HOx radicals was conducted at a coastal site in the Pearl River Delta. Radical chemistry was influenced by different air masses in a time-dependent way. Land mass promotes a more active photochemical process, with daily averages of 7.1 × 106 and 5.2 × 108 cm−3 for OH and HO2 respectively. The rapid oxidation process was accompanied by a higher diurnal HONO concentration, which influences the ozone-sensitive system and eventually magnifies the background ozone.
Sarah Albertin, Joël Savarino, Slimane Bekki, Albane Barbero, Roberto Grilli, Quentin Fournier, Irène Ventrillard, Nicolas Caillon, and Kathy Law
Atmos. Chem. Phys., 24, 1361–1388, https://doi.org/10.5194/acp-24-1361-2024, https://doi.org/10.5194/acp-24-1361-2024, 2024
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This study reports the first simultaneous records of oxygen (Δ17O) and nitrogen (δ15N) isotopes in nitrogen dioxide (NO2) and nitrate (NO3−). These data are combined with atmospheric observations to explore sub-daily N reactive chemistry and quantify N fractionation effects in an Alpine winter city. The results highlight the necessity of using Δ17O and δ15N in both NO2 and NO3− to avoid biased estimations of NOx sources and fates from NO3− isotopic records in urban winter environments.
Shigeyuki Ishidoya, Kazuhiro Tsuboi, Hiroaki Kondo, Kentaro Ishijima, Nobuyuki Aoki, Hidekazu Matsueda, and Kazuyuki Saito
Atmos. Chem. Phys., 24, 1059–1077, https://doi.org/10.5194/acp-24-1059-2024, https://doi.org/10.5194/acp-24-1059-2024, 2024
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A method evaluating techniques for carbon neutrality, such as carbon capture and storage (CCS), is important. This study presents a method to evaluate CO2 emissions from a cement plant based on atmospheric O2 and CO2 measurements. The method will also be useful for evaluating CO2 capture from flue gas at CCS plants, since the plants remove CO2 from the atmosphere without causing any O2 changes, just as cement plants do, differing only in the direction of CO2 exchange with the atmosphere.
Magdalena Pühl, Anke Roiger, Alina Fiehn, Alan M. Gorchov Negron, Eric A. Kort, Stefan Schwietzke, Ignacio Pisso, Amy Foulds, James Lee, James L. France, Anna E. Jones, Dave Lowry, Rebecca E. Fisher, Langwen Huang, Jacob Shaw, Prudence Bateson, Stephen Andrews, Stuart Young, Pamela Dominutti, Tom Lachlan-Cope, Alexandra Weiss, and Grant Allen
Atmos. Chem. Phys., 24, 1005–1024, https://doi.org/10.5194/acp-24-1005-2024, https://doi.org/10.5194/acp-24-1005-2024, 2024
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In April–May 2019 we carried out an airborne field campaign in the southern North Sea with the aim of studying methane emissions of offshore gas installations. We determined methane emissions from elevated methane measured downstream of the sampled installations. We compare our measured methane emissions with estimated methane emissions from national and global annual inventories. As a result, we find inconsistencies of inventories and large discrepancies between measurements and inventories.
Georgios I. Gkatzelis, Matthew M. Coggon, Chelsea E. Stockwell, Rebecca S. Hornbrook, Hannah Allen, Eric C. Apel, Megan M. Bela, Donald R. Blake, Ilann Bourgeois, Steven S. Brown, Pedro Campuzano-Jost, Jason M. St. Clair, James H. Crawford, John D. Crounse, Douglas A. Day, Joshua P. DiGangi, Glenn S. Diskin, Alan Fried, Jessica B. Gilman, Hongyu Guo, Johnathan W. Hair, Hannah S. Halliday, Thomas F. Hanisco, Reem Hannun, Alan Hills, L. Gregory Huey, Jose L. Jimenez, Joseph M. Katich, Aaron Lamplugh, Young Ro Lee, Jin Liao, Jakob Lindaas, Stuart A. McKeen, Tomas Mikoviny, Benjamin A. Nault, J. Andrew Neuman, John B. Nowak, Demetrios Pagonis, Jeff Peischl, Anne E. Perring, Felix Piel, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Thomas B. Ryerson, Melinda K. Schueneman, Rebecca H. Schwantes, Joshua P. Schwarz, Kanako Sekimoto, Vanessa Selimovic, Taylor Shingler, David J. Tanner, Laura Tomsche, Krystal T. Vasquez, Patrick R. Veres, Rebecca Washenfelder, Petter Weibring, Paul O. Wennberg, Armin Wisthaler, Glenn M. Wolfe, Caroline C. Womack, Lu Xu, Katherine Ball, Robert J. Yokelson, and Carsten Warneke
Atmos. Chem. Phys., 24, 929–956, https://doi.org/10.5194/acp-24-929-2024, https://doi.org/10.5194/acp-24-929-2024, 2024
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This study reports emissions of gases and particles from wildfires. These emissions are related to chemical proxies that can be measured by satellite and incorporated into models to improve predictions of wildfire impacts on air quality and climate.
Jie Wang, Haichao Wang, Yee Jun Tham, Lili Ming, Zelong Zheng, Guizhen Fang, Cuizhi Sun, Zhenhao Ling, Jun Zhao, and Shaojia Fan
Atmos. Chem. Phys., 24, 977–992, https://doi.org/10.5194/acp-24-977-2024, https://doi.org/10.5194/acp-24-977-2024, 2024
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Many works report NO3 chemistry in inland regions while less target marine regions. We measured N2O5 and related species on a typical island and found intensive nighttime chemistry and rapid NO3 loss. NO contributed significantly to NO3 loss despite its sub-ppbv level, suggesting nocturnal NO3 reactions would be largely enhanced once free from NO emissions in the open ocean. This highlights the strong influences of urban outflow on downward marine areas in terms of nighttime chemistry.
Tanja J. Schuck, Johannes Degen, Eric Hintsa, Peter Hoor, Markus Jesswein, Timo Keber, Daniel Kunkel, Fred Moore, Florian Obersteiner, Matt Rigby, Thomas Wagenhäuser, Luke M. Western, Andreas Zahn, and Andreas Engel
Atmos. Chem. Phys., 24, 689–705, https://doi.org/10.5194/acp-24-689-2024, https://doi.org/10.5194/acp-24-689-2024, 2024
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We study the interhemispheric gradient of sulfur hexafluoride (SF6), a strong long-lived greenhouse gas. Its emissions are stronger in the Northern Hemisphere; therefore, mixing ratios in the Southern Hemisphere lag behind. Comparing the observations to a box model, the model predicts air in the Southern Hemisphere to be older. For a better agreement, the emissions used as model input need to be increased (and their spatial pattern changed), and we need to modify north–south transport.
Jérémy Gueffier, François Gheusi, Marie Lothon, Véronique Pont, Alban Philibert, Fabienne Lohou, Solène Derrien, Yannick Bezombes, Gilles Athier, Yves Meyerfeld, Antoine Vial, and Emmanuel Leclerc
Atmos. Chem. Phys., 24, 287–316, https://doi.org/10.5194/acp-24-287-2024, https://doi.org/10.5194/acp-24-287-2024, 2024
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This study investigates the link between weather regime and atmospheric composition at a Pyrenean observatory. Five years of meteorological data were synchronized on a daily basis and then, using a clustering method, separated into six groups of observation days, with most showing marked characteristics of different weather regimes (fair and disturbed weather, winter windstorms, foehn). Statistical differences in gas and particle concentrations appeared between the groups and are discussed.
Nathaniel Brockway, Peter K. Peterson, Katja Bigge, Kristian D. Hajny, Paul B. Shepson, Kerri A. Pratt, Jose D. Fuentes, Tim Starn, Robert Kaeser, Brian H. Stirm, and William R. Simpson
Atmos. Chem. Phys., 24, 23–40, https://doi.org/10.5194/acp-24-23-2024, https://doi.org/10.5194/acp-24-23-2024, 2024
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Bromine monoxide (BrO) strongly affects atmospheric chemistry in the springtime Arctic, yet there are still many uncertainties around its sources and recycling, particularly in the context of a rapidly changing Arctic. In this study, we observed BrO as a function of altitude above the Alaskan Arctic. We found that BrO was often most concentrated near the ground, confirming the ability of snow to produce and recycle reactive bromine, and identified four common vertical distributions of BrO.
Alina Fiehn, Maximilian Eckl, Julian Kostinek, Michał Gałkowski, Christoph Gerbig, Michael Rothe, Thomas Röckmann, Malika Menoud, Hossein Maazallahi, Martina Schmidt, Piotr Korbeń, Jarosław Neçki, Mila Stanisavljević, Justyna Swolkień, Andreas Fix, and Anke Roiger
Atmos. Chem. Phys., 23, 15749–15765, https://doi.org/10.5194/acp-23-15749-2023, https://doi.org/10.5194/acp-23-15749-2023, 2023
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During the CoMet mission in the Upper Silesian Coal Basin (USCB) ground-based and airborne air samples were taken and analyzed for the isotopic composition of CH4 to derive the mean signature of the USCB and source signatures of individual coal mines. Using δ2H signatures, the biogenic emissions from the USCB account for 15 %–50 % of total emissions, which is underestimated in common emission inventories. This demonstrates the importance of δ2H-CH4 observations for methane source apportionment.
Yifei Song, Chaoyang Xue, Yuanyuan Zhang, Pengfei Liu, Fengxia Bao, Xuran Li, and Yujing Mu
Atmos. Chem. Phys., 23, 15733–15747, https://doi.org/10.5194/acp-23-15733-2023, https://doi.org/10.5194/acp-23-15733-2023, 2023
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We present measurements of HONO flux and related parameters over an agricultural field during a whole growing season of summer maize. This dataset allows studies on the characteristics and influencing factors of soil HONO emissions, determination of HONO emission factors, estimation of total HONO emissions at a national scale, and the discussion on future environmental policies in terms of mitigating regional air pollution.
Can Ye, Keding Lu, Xuefei Ma, Wanyi Qiu, Shule Li, Xinping Yang, Chaoyang Xue, Tianyu Zhai, Yuhan Liu, Xuan Li, Yang Li, Haichao Wang, Zhaofeng Tan, Xiaorui Chen, Huabin Dong, Limin Zeng, Min Hu, and Yuanhang Zhang
Atmos. Chem. Phys., 23, 15455–15472, https://doi.org/10.5194/acp-23-15455-2023, https://doi.org/10.5194/acp-23-15455-2023, 2023
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In this study, combining comprehensive field measurements and a box model, we found NO2 conversion on the ground surface was the most important source for HONO production among the proposed heterogeneous and gas-phase HONO sources. In addition, HONO was found to evidently enhance O3 production and aggravate O3 pollution in summer in China. Our study improved our understanding of the relative importance of different HONO sources and the crucial role of HONO in O3 formation in polluted areas.
Yann Cohen, Didier Hauglustaine, Bastien Sauvage, Susanne Rohs, Patrick Konjari, Ulrich Bundke, Andreas Petzold, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 23, 14973–15009, https://doi.org/10.5194/acp-23-14973-2023, https://doi.org/10.5194/acp-23-14973-2023, 2023
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The upper troposphere–lower stratosphere (UTLS) is a key region regarding the lower atmospheric composition. This study consists of a comprehensive evaluation of an up-to-date chemistry–climate model in this layer, using regular in situ measurements based on passenger aircraft. For this purpose, a specific software (Interpol-IAGOS) has been updated and made publicly available. The model reproduces the carbon monoxide peaks due to biomass burning over the continental tropics particularly well.
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.
Xuelian Zhong, Hengqing Shen, Min Zhao, Ji Zhang, Yue Sun, Yuhong Liu, Yingnan Zhang, Ye Shan, Hongyong Li, Jiangshan Mu, Yu Yang, Yanqiu Nie, Jinghao Tang, Can Dong, Xinfeng Wang, Yujiao Zhu, Mingzhi Guo, Wenxing Wang, and Likun Xue
Atmos. Chem. Phys., 23, 14761–14778, https://doi.org/10.5194/acp-23-14761-2023, https://doi.org/10.5194/acp-23-14761-2023, 2023
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Nitrous acid (HONO) is vital for atmospheric oxidation. In research at Mount Lao, China, models revealed a significant unidentified marine HONO source. Overlooking this could skew our understanding of air quality and climate change. This finding emphasizes HONO’s importance in the coastal atmosphere, uncovering previously unnoticed interactions.
Junwei Song, Harald Saathoff, Feng Jiang, Linyu Gao, Hengheng Zhang, and Thomas Leisner
EGUsphere, https://doi.org/10.5194/egusphere-2023-2255, https://doi.org/10.5194/egusphere-2023-2255, 2023
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This study presents the concurrent online measurements of organic gas and particles (VOCs and OA) at a forest site in summer. Both VOCs and OA were largely contributed by oxygenated organic compounds. Semi-volatile oxygenated OA and organic nitrate formed from monoterpenes and sesquiterpenes contribute significantly to nighttime particle growth. The results help to understand the causes of nighttime particle growth regularly observed in summer in the central European rural forested environments.
Steven Job Thomas, Toni Tykkä, Heidi Hellén, Federico Bianchi, and Arnaud P. Praplan
Atmos. Chem. Phys., 23, 14627–14642, https://doi.org/10.5194/acp-23-14627-2023, https://doi.org/10.5194/acp-23-14627-2023, 2023
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The study employed total ozone reactivity to demonstrate how emissions of Norway spruce readily react with ozone and could be a major ozone sink, particularly under stress. Additionally, this approach provided insight into the limitations of current analytical techniques that measure the compounds present or emitted into the atmosphere. The study shows how the technique used was not enough to measure all compounds emitted, and this could potentially underestimate various atmospheric processes.
Jinsol Kim, John B. Miller, Charles E. Miller, Scott J. Lehman, Sylvia E. Michel, Vineet Yadav, Nick E. Rollins, and William M. Berelson
Atmos. Chem. Phys., 23, 14425–14436, https://doi.org/10.5194/acp-23-14425-2023, https://doi.org/10.5194/acp-23-14425-2023, 2023
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In this study, we present the partitioning of CO2 signals from biogenic, petroleum and natural gas sources by combining CO, 13CO2 and 14CO2 measurements. Using measurements from flask air samples at three sites in the greater Los Angeles region, we find larger and positive contributions of biogenic signals in winter and smaller and negative contributions in summer. The largest contribution of natural gas combustion generally occurs in summer.
Robert Woodward-Massey, Roberto Sommariva, Lisa K. Whalley, Danny R. Cryer, Trevor Ingham, William J. Bloss, Stephen M. Ball, Sam Cox, James D. Lee, Chris P. Reed, Leigh R. Crilley, Louisa J. Kramer, Brian J. Bandy, Grant L. Forster, Claire E. Reeves, Paul S. Monks, and Dwayne E. Heard
Atmos. Chem. Phys., 23, 14393–14424, https://doi.org/10.5194/acp-23-14393-2023, https://doi.org/10.5194/acp-23-14393-2023, 2023
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Measurements of OH, HO2 and RO2 radicals and also OH reactivity were made at a UK coastal site and compared to calculations from a constrained box model utilising the Master Chemical Mechanism. The model agreement displayed a strong dependence on the NO concentration. An experimental budget analysis for OH, HO2, RO2 and total ROx demonstrated significant imbalances between HO2 and RO2 production rates. Ozone production rates were calculated from measured radicals and compared to modelled values.
Leonard Kirago, Örjan Gustafsson, Samuel Mwaniki Gaita, Sophie L. Haslett, Michael J. Gatari, Maria Elena Popa, Thomas Röckmann, Christoph Zellweger, Martin Steinbacher, Jörg Klausen, Christian Félix, David Njiru, and August Andersson
Atmos. Chem. Phys., 23, 14349–14357, https://doi.org/10.5194/acp-23-14349-2023, https://doi.org/10.5194/acp-23-14349-2023, 2023
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This study provides ground-observational evidence that supports earlier suggestions that savanna fires are the main emitters and modulators of carbon monoxide gas in Africa. Using isotope-based techniques, the study has shown that about two-thirds of this gas is emitted from savanna fires, while for urban areas, in this case Nairobi, primary sources approach 100 %. The latter has implications for air quality policy, suggesting primary emissions such as traffic should be targeted.
Heidi Hellén, Rostislav Kouznetsov, Kaisa Kraft, Jukka Seppälä, Mika Vestenius, Jukka-Pekka Jalkanen, Lauri Laakso, and Hannele Hakola
EGUsphere, https://doi.org/10.5194/egusphere-2023-2323, https://doi.org/10.5194/egusphere-2023-2323, 2023
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Mixing ratios of C2-C5 NMHCs and methanethiol were measured on an island in Baltic Sea using an in-situ gas chromatograph. Shipping emissions were found to be an important source of ethene, ethyne, propene and benzene. High summertime mixing ratios of methanethiol and dependence of mixing ratios on sea water temperature and height indicated the biogenic origin possibly from phytoplankton or macroalgae. These emissions may have strong impacts on SO2 production and new particle formation.
Rebecca M. Garland, Katye E. Altieri, Laura Dawidowski, Laura Gallardo, Aderiana Mbandi, Nestor Y. Rojas, and N'datchoh E. Touré
EGUsphere, https://doi.org/10.5194/egusphere-2023-2566, https://doi.org/10.5194/egusphere-2023-2566, 2023
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In this opinion, we focus on two geographical areas in the Global South to discuss some common challenges and constraints, with a focus on our strengths in atmospheric science research. It is these strengths, we believe, that highlight the critical role of Global South researchers in the future of atmospheric science research.
Clara M. Nussbaumer, Bryan K. Place, Qindan Zhu, Eva Y. Pfannerstill, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Ryan Ward, Anthony Bucholtz, John H. Seinfeld, Allen H. Goldstein, and Ronald C. Cohen
Atmos. Chem. Phys., 23, 13015–13028, https://doi.org/10.5194/acp-23-13015-2023, https://doi.org/10.5194/acp-23-13015-2023, 2023
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NOx is a precursor to hazardous tropospheric ozone and can be emitted from various anthropogenic sources. It is important to quantify NOx emissions in urban environments to improve the local air quality, which still remains a challenge, as sources are heterogeneous in space and time. In this study, we calculate NOx emissions over Los Angeles, based on aircraft measurements in June 2021, and compare them to a local emission inventory, which we find mostly overpredicts the measured values.
Magdalena Okuljar, Olga Garmash, Miska Olin, Joni Kalliokoski, Hilkka Timonen, Jarkko V. Niemi, Pauli Paasonen, Jenni Kontkanen, Yanjun Zhang, Heidi Hellén, Heino Kuuluvainen, Minna Aurela, Hanna E. Manninen, Mikko Sipilä, Topi Rönkkö, Tuukka Petäjä, Markku Kulmala, Miikka Dal Maso, and Mikael Ehn
Atmos. Chem. Phys., 23, 12965–12983, https://doi.org/10.5194/acp-23-12965-2023, https://doi.org/10.5194/acp-23-12965-2023, 2023
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Highly oxygenated organic molecules (HOMs) form secondary organic aerosol that affects air quality and health. In this study, we demonstrate that in a moderately polluted city with abundant vegetation, the composition of HOMs is largely controlled by the effect of NOx on the biogenic volatile organic compound oxidation. Comparing the results from two nearby stations, we show that HOM composition and formation pathways can change considerably within small distances in urban environments.
Si-Wan Kim, Kyoung-Min Kim, Yujoo Jeong, Seunghwan Seo, Yeonsu Park, and Jeongyeon Kim
Atmos. Chem. Phys., 23, 12867–12886, https://doi.org/10.5194/acp-23-12867-2023, https://doi.org/10.5194/acp-23-12867-2023, 2023
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Surface ozone is a pollutant regulated for public health. This study derived surface ozone trends over South Korea from 2001 to 2021 and highlighted that South Korea has been a nonattainment area since 2010, based on the US EPA standard. However, the occurrences of high ozone condition decreased in spring during the COVID-19 pandemic, partly due to large reductions of ozone precursor concentrations in China and South Korea.
Zeyu Sun, Zheng Zong, Yang Tan, Chongguo Tian, Zeyu Liu, Fan Zhang, Rong Sun, Yingjun Chen, Jun Li, and Gan Zhang
Atmos. Chem. Phys., 23, 12851–12865, https://doi.org/10.5194/acp-23-12851-2023, https://doi.org/10.5194/acp-23-12851-2023, 2023
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This is the first report of ship-emitted nitrogen stable isotope composition (δ15N) of nitrogen oxides (NOx). The results showed that δ15N–NOx from ships was −18.5 ± 10.9 ‰ and increased monotonically with tightening emission regulations. The selective catalytic reduction system was the most vital factor. The temporal variation in δ15N–NOx was evaluated and can be used to select suitable δ15N–NOx for a more accurate assessment of the contribution of ship-emitted exhaust to atmospheric NOx.
Eva Y. Pfannerstill, Caleb Arata, Qindan Zhu, Benjamin C. Schulze, Roy Woods, John H. Seinfeld, Anthony Bucholtz, Ronald C. Cohen, and Allen H. Goldstein
Atmos. Chem. Phys., 23, 12753–12780, https://doi.org/10.5194/acp-23-12753-2023, https://doi.org/10.5194/acp-23-12753-2023, 2023
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The San Joaquin Valley is an agricultural area with poor air quality. Organic gases drive the formation of hazardous air pollutants. Agricultural emissions of these gases are not well understood and have rarely been quantified at landscape scale. By combining aircraft-based emission measurements with land cover information, we found mis- or unrepresented emission sources. Our results help in understanding of pollution sources and in improving predictions of air quality in agricultural regions.
Youwei Hong, Keran Zhang, Dan Liao, Gaojie Chen, Min Zhao, Yiling Lin, Xiaoting Ji, Ke Xu, Yu Wu, Ruilian Yu, Gongren Hu, Sung-Deuk Choi, Likun Xue, and Jinsheng Chen
Atmos. Chem. Phys., 23, 10795–10807, https://doi.org/10.5194/acp-23-10795-2023, https://doi.org/10.5194/acp-23-10795-2023, 2023
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Particle uptakes of HCHO and the impacts on PM2.5 and O3 production remain highly uncertain. Based on the investigation of co-occurring wintertime O3 and PM2.5 pollution in a coastal city of southeast China, we found enhanced heterogeneous formation of hydroxymethanesulfonate (HMS) and increased ROx concentrations and net O3 production rates. The findings of this study are helpful to better explore the mechanisms of key precursors for co-occurring PM2.5 and O3 pollution.
Foteini Stavropoulou, Katarina Vinković, Bert Kers, Marcel de Vries, Steven van Heuven, Piotr Korbeń, Martina Schmidt, Julia Wietzel, Pawel Jagoda, Jaroslav M. Necki, Jakub Bartyzel, Hossein Maazallahi, Malika Menoud, Carina van der Veen, Sylvia Walter, Béla Tuzson, Jonas Ravelid, Randulph Paulo Morales, Lukas Emmenegger, Dominik Brunner, Michael Steiner, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, Hugo Denier van der Gon, Antonio Delre, Maklawe Essonanawe Edjabou, Charlotte Scheutz, Marius Corbu, Sebastian Iancu, Denisa Moaca, Alin Scarlat, Alexandru Tudor, Ioana Vizireanu, Andreea Calcan, Magdalena Ardelean, Sorin Ghemulet, Alexandru Pana, Aurel Constantinescu, Lucian Cusa, Alexandru Nica, Calin Baciu, Cristian Pop, Andrei Radovici, Alexandru Mereuta, Horatiu Stefanie, Alexandru Dandocsi, Bas Hermans, Stefan Schwietzke, Daniel Zavala-Araiza, Huilin Chen, and Thomas Röckmann
Atmos. Chem. Phys., 23, 10399–10412, https://doi.org/10.5194/acp-23-10399-2023, https://doi.org/10.5194/acp-23-10399-2023, 2023
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In this study, we quantify CH4 emissions from onshore oil production sites in Romania at source and facility level using a combination of ground- and drone-based measurement techniques. We show that the total CH4 emissions in our studied areas are much higher than the emissions reported to UNFCCC, and up to three-quarters of the detected emissions are related to operational venting. Our results suggest that oil and gas production infrastructure in Romania holds a massive mitigation potential.
Chunxiang Ye, Shuzheng Guo, Weili Lin, Fangjie Tian, Jianshu Wang, Chong Zhang, Suzhen Chi, Yi Chen, Yingjie Zhang, Limin Zeng, Xin Li, Duo Bu, Jiacheng Zhou, and Weixiong Zhao
Atmos. Chem. Phys., 23, 10383–10397, https://doi.org/10.5194/acp-23-10383-2023, https://doi.org/10.5194/acp-23-10383-2023, 2023
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Online volatile organic compound (VOC) measurements by gas chromatography–mass spectrometry, with other O3 precursors, were used to identify key VOC and other key sources in Lhasa. Total VOCs (TVOCs), alkanes, and aromatics are half as abundant as in Beijing. Oxygenated VOCs (OVOCs) consist of 52 % of the TVOCs. Alkenes and OVOCs account for 80 % of the ozone formation potential. Aromatics dominate secondary organic aerosol potential. Positive matrix factorization decomposed residential sources.
Brandon Bottorff, Michelle M. Lew, Youngjun Woo, Pamela Rickly, Matthew D. Rollings, Benjamin Deming, Daniel C. Anderson, Ezra Wood, Hariprasad D. Alwe, Dylan B. Millet, Andrew Weinheimer, Geoff Tyndall, John Ortega, Sebastien Dusanter, Thierry Leonardis, James Flynn, Matt Erickson, Sergio Alvarez, Jean C. Rivera-Rios, Joshua D. Shutter, Frank Keutsch, Detlev Helmig, Wei Wang, Hannah M. Allen, Johnathan H. Slade, Paul B. Shepson, Steven Bertman, and Philip S. Stevens
Atmos. Chem. Phys., 23, 10287–10311, https://doi.org/10.5194/acp-23-10287-2023, https://doi.org/10.5194/acp-23-10287-2023, 2023
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The hydroxyl (OH), hydroperoxy (HO2), and organic peroxy (RO2) radicals play important roles in atmospheric chemistry and have significant air quality implications. Here, we compare measurements of OH, HO2, and total peroxy radicals (XO2) made in a remote forest in Michigan, USA, to predictions from a series of chemical models. Lower measured radical concentrations suggest that the models may be missing an important radical sink and overestimating the rate of ozone production in this forest.
Jenny Oh, Chubashini Shunthirasingham, Ying Duan Lei, Faqiang Zhan, Yuening Li, Abigaëlle Dalpé Castilloux, Amina Ben Chaaben, Zhe Lu, Kelsey Lee, Frank A. P. C. Gobas, Sabine Eckhardt, Nick Alexandrou, Hayley Hung, and Frank Wania
Atmos. Chem. Phys., 23, 10191–10205, https://doi.org/10.5194/acp-23-10191-2023, https://doi.org/10.5194/acp-23-10191-2023, 2023
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An emerging brominated flame retardant (BFR) called TBECH (1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane) has never been produced or imported for use in Canada yet is found to be one of the most abundant gaseous BFRs in the Canadian atmosphere. The recorded spatial and temporal variability of TBECH suggest that the release from imported consumer products containing TBECH is the most likely explanation for its environmental occurrence in Canada.
Olivia E. Clifton, Donna Schwede, Christian Hogrefe, Jesse O. Bash, Sam Bland, Philip Cheung, Mhairi Coyle, Lisa Emberson, Johannes Flemming, Erick Fredj, Stefano Galmarini, Laurens Ganzeveld, Orestis Gazetas, Ignacio Goded, Christopher D. Holmes, László Horváth, Vincent Huijnen, Qian Li, Paul A. Makar, Ivan Mammarella, Giovanni Manca, J. William Munger, Juan L. Pérez-Camanyo, Jonathan Pleim, Limei Ran, Roberto San Jose, Sam J. Silva, Ralf Staebler, Shihan Sun, Amos P. K. Tai, Eran Tas, Timo Vesala, Tamás Weidinger, Zhiyong Wu, and Leiming Zhang
Atmos. Chem. Phys., 23, 9911–9961, https://doi.org/10.5194/acp-23-9911-2023, https://doi.org/10.5194/acp-23-9911-2023, 2023
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A primary sink of air pollutants is dry deposition. Dry deposition estimates differ across the models used to simulate atmospheric chemistry. Here, we introduce an effort to examine dry deposition schemes from atmospheric chemistry models. We provide our approach’s rationale, document the schemes, and describe datasets used to drive and evaluate the schemes. We also launch the analysis of results by evaluating against observations and identifying the processes leading to model–model differences.
Qindan Zhu, Bryan Place, Eva Y. Pfannerstill, Sha Tong, Huanxin Zhang, Jun Wang, Clara M. Nussbaumer, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Anthony Bucholtz, John H. Seinfeld, Allen H. Goldstein, and Ronald C. Cohen
Atmos. Chem. Phys., 23, 9669–9683, https://doi.org/10.5194/acp-23-9669-2023, https://doi.org/10.5194/acp-23-9669-2023, 2023
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Nitrogen oxide (NOx) is a hazardous air pollutant, and it is the precursor of short-lived climate forcers like tropospheric ozone and aerosol particles. While NOx emissions from transportation has been strictly regulated, soil NOx emissions are overlooked. We use the airborne flux measurements to observe NOx emissions from highways and urban and cultivated soil land cover types. We show non-negligible soil NOx emissions, which are significantly underestimated in current model simulations.
Xin Yang, Kimberly Strong, Alison Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley Walker, Sara Morris, and Peter Effertz
EGUsphere, https://doi.org/10.5194/egusphere-2023-1446, https://doi.org/10.5194/egusphere-2023-1446, 2023
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This study uses in-situ field data collected from a Canadian high Arctic site to demonstrate that surface snow in early spring is a net sink of atmospheric bromine and nitrogen. In addition, surface snow bromide and nitrate are significantly correlated, one molecule bromide deposited is accompanied by 4–7 molecules nitrate, indicating the oxidation of reactive nitrogen is accelerated by reactive bromine. This is the first time such an effect was seen in snow chemistry on a time scale of one day.
Money Ossohou, Jonathan Edward Hickman, Lieven Clarisse, Pierre-François Coheur, Martin Van Damme, Marcellin Adon, Véronique Yoboué, Eric Gardrat, Maria Dias Alvès, and Corinne Galy-Lacaux
Atmos. Chem. Phys., 23, 9473–9494, https://doi.org/10.5194/acp-23-9473-2023, https://doi.org/10.5194/acp-23-9473-2023, 2023
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The updated analyses of ground-based concentrations and satellite total vertical columns of atmospheric ammonia help us to better understand 21st century ammonia dynamics in sub-Saharan Africa. We conclude that the drivers of trends are agriculture in the dry savanna of Katibougou, Mali; air temperature and agriculture in the wet savanna of Djougou, Benin, and Lamto, Côte d'Ivoire; and leaf area index, air temperature, residential, and agriculture in forests of Bomassa, Republic of Congo.
Hyeri Park, Jooil Kim, Haklim Choi, Sohyeon Geum, Yeaseul Kim, Rona L. Thompson, Jens Mühle, Peter K. Salameh, Christina M. Harth, Kieran M. Stanley, Simon O'Doherty, Paul J. Fraser, Peter G. Simmonds, Paul B. Krummel, Ray F. Weiss, Ronald G. Prinn, and Sunyoung Park
Atmos. Chem. Phys., 23, 9401–9411, https://doi.org/10.5194/acp-23-9401-2023, https://doi.org/10.5194/acp-23-9401-2023, 2023
Short summary
Short summary
Based on atmospheric HFC-23 observations, the first estimate of post-CDM HFC-23 emissions in eastern Asia for 2008–2019 shows that these emissions contribute significantly to the global emissions rise. The observation-derived emissions were much larger than the bottom-up estimates expected to approach zero after 2015 due to national abatement activities. These discrepancies could be attributed to unsuccessful factory-level HFC-23 abatement and inaccurate quantification of emission reductions.
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Short summary
This study provides information about the regional variabilities in some of the pollutants using observations in Nepal and India. It is shown that agricultural crop residue burning leads to a significant enhancement in ozone and CO over a wider region. Further, the wintertime higher ozone levels are shown to be largely due to local emissions, while regional transport could be important in spring and hence shows the role of regional sources versus local sources in the Kathmandu Valley.
This study provides information about the regional variabilities in some of the pollutants using...
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