Articles | Volume 24, issue 3
https://doi.org/10.5194/acp-24-1855-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-24-1855-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Feb 2024
Research article |
| 12 Feb 2024
| 12 Feb 2024
Revisiting day-of-week ozone patterns in an era of evolving US air quality
Office of Air and Radiation, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Christian Hogrefe
Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Andrew Whitehill
Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Kristen M. Foley
Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Jennifer Liljegren
Region 5, U.S. Environmental Protection Agency, Chicago, IL, USA
Norm Possiel
Office of Air and Radiation, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Benjamin Wells
Office of Air and Radiation, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Barron H. Henderson
Office of Air and Radiation, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Lukas C. Valin
Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Gail Tonnesen
Region 8, U.S. Environmental Protection Agency, Denver, CO, USA
K. Wyat Appel
Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
Shannon Koplitz
Office of Air and Radiation, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
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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.
Syuichi Itahashi, Rohit Mathur, Christian Hogrefe, Sergey L. Napelenok, and Yang Zhang
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Benjamin N. Murphy, Christopher G. Nolte, Fahim Sidi, Jesse O. Bash, K. Wyat Appel, Carey Jang, Daiwen Kang, James Kelly, Rohit Mathur, Sergey Napelenok, George Pouliot, and Havala O. T. Pye
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K. Wyat Appel, Jesse O. Bash, Kathleen M. Fahey, Kristen M. Foley, Robert C. Gilliam, Christian Hogrefe, William T. Hutzell, Daiwen Kang, Rohit Mathur, Benjamin N. Murphy, Sergey L. Napelenok, Christopher G. Nolte, Jonathan E. Pleim, George A. Pouliot, Havala O. T. Pye, Limei Ran, Shawn J. Roselle, Golam Sarwar, Donna B. Schwede, Fahim I. Sidi, Tanya L. Spero, and David C. Wong
Geosci. Model Dev., 14, 2867–2897, https://doi.org/10.5194/gmd-14-2867-2021, https://doi.org/10.5194/gmd-14-2867-2021, 2021
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This paper details the scientific updates in the recently released CMAQ version 5.3 (and v5.3.1) and also includes operational and diagnostic evaluations of CMAQv5.3.1 against observations and the previous version of the CMAQ (v5.2.1). This work was done to improve the underlying science in CMAQ. This article is used to inform the CMAQ modeling community of the updates to the modeling system and the expected change in model performance from these updates (versus the previous model version).
Qian Shu, Benjamin Murphy, Jonathan E. Pleim, Donna Schwede, Barron H. Henderson, Havala O.T. Pye, Keith Wyat Appel, Tanvir R. Khan, and Judith A. Perlinger
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-129, https://doi.org/10.5194/gmd-2021-129, 2021
Preprint withdrawn
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Russell W. Long, Andrew Whitehill, Andrew Habel, Shawn Urbanski, Hannah Halliday, Maribel Colón, Surender Kaushik, and Matthew S. Landis
Atmos. Meas. Tech., 14, 1783–1800, https://doi.org/10.5194/amt-14-1783-2021, https://doi.org/10.5194/amt-14-1783-2021, 2021
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Elena Spinei, Martin Tiefengraber, Moritz Müller, Manuel Gebetsberger, Alexander Cede, Luke Valin, James Szykman, Andrew Whitehill, Alexander Kotsakis, Fernando Santos, Nader Abbuhasan, Xiaoyi Zhao, Vitali Fioletov, Sum Chi Lee, and Robert Swap
Atmos. Meas. Tech., 14, 647–663, https://doi.org/10.5194/amt-14-647-2021, https://doi.org/10.5194/amt-14-647-2021, 2021
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Plastics are widely used in everyday life and scientific equipment. This paper presents Delrin plastic off-gassing as a function of temperature on the atmospheric measurements of formaldehyde by Pandora spectroscopic instruments. The sealed telescope assembly containing Delrin components emitted large amounts of formaldehyde at 30–45 °C, interfering with the Pandora measurements. These results have a broader implication since electronic products often experience the same temperature.
Huiying Luo, Marina Astitha, Christian Hogrefe, Rohit Mathur, and S. Trivikrama Rao
Atmos. Chem. Phys., 20, 13801–13815, https://doi.org/10.5194/acp-20-13801-2020, https://doi.org/10.5194/acp-20-13801-2020, 2020
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A new method is introduced to evaluate nonlinear, nonstationary modeled PM2.5 time series by decomposing decadal PM2.5 concentrations and its species onto various timescales. It does not require preselection of temporal scales and assumptions of linearity and stationarity. It provides a unique opportunity to assess the influence of each species on total PM2.5. The results reveal a phase shift in modeled EC/OC concentrations, indicating the need for improved model treatment of organic aerosols.
Laura M. Judd, Jassim A. Al-Saadi, James J. Szykman, Lukas C. Valin, Scott J. Janz, Matthew G. Kowalewski, Henk J. Eskes, J. Pepijn Veefkind, Alexander Cede, Moritz Mueller, Manuel Gebetsberger, Robert Swap, R. Bradley Pierce, Caroline R. Nowlan, Gonzalo González Abad, Amin Nehrir, and David Williams
Atmos. Meas. Tech., 13, 6113–6140, https://doi.org/10.5194/amt-13-6113-2020, https://doi.org/10.5194/amt-13-6113-2020, 2020
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This paper evaluates Sentinel-5P TROPOMI v1.2 NO2 tropospheric columns over New York City using data from airborne mapping spectrometers and a network of ground-based spectrometers (Pandora) collected in 2018. These evaluations consider impacts due to cloud parameters, a priori profile assumptions, and spatial and temporal variability. Overall, TROPOMI tropospheric NO2 columns appear to have a low bias in this region.
Amy E. Christiansen, Annmarie G. Carlton, and Barron H. Henderson
Atmos. Chem. Phys., 20, 11607–11624, https://doi.org/10.5194/acp-20-11607-2020, https://doi.org/10.5194/acp-20-11607-2020, 2020
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We quantify differences in surface-level fine particle mass (PM2.5) chemical composition in relation to satellite-derived cloud flags and find significant differences between clear-sky and cloud days. The work suggests that future analysis in this area is warranted.
Sungyeon Choi, Lok N. Lamsal, Melanie Follette-Cook, Joanna Joiner, Nickolay A. Krotkov, William H. Swartz, Kenneth E. Pickering, Christopher P. Loughner, Wyat Appel, Gabriele Pfister, Pablo E. Saide, Ronald C. Cohen, Andrew J. Weinheimer, and Jay R. Herman
Atmos. Meas. Tech., 13, 2523–2546, https://doi.org/10.5194/amt-13-2523-2020, https://doi.org/10.5194/amt-13-2523-2020, 2020
Syuichi Itahashi, Rohit Mathur, Christian Hogrefe, and Yang Zhang
Atmos. Chem. Phys., 20, 3373–3396, https://doi.org/10.5194/acp-20-3373-2020, https://doi.org/10.5194/acp-20-3373-2020, 2020
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The state-of-the-science Community Multiscale Air Quality model extended for hemispheric applications (H-CMAQ) is used to model the trans-Pacific transport which has been recognized as a potential source of air pollutants over the US. In Part 1, modeled ozone is evaluated with observations at surface, by ozonesonde and airplane, and by satellite across the Northern Hemisphere. In addition, a newly developed air mass characterization method to estimate stratospheric intrusion is presented.
Syuichi Itahashi, Rohit Mathur, Christian Hogrefe, Sergey L. Napelenok, and Yang Zhang
Atmos. Chem. Phys., 20, 3397–3413, https://doi.org/10.5194/acp-20-3397-2020, https://doi.org/10.5194/acp-20-3397-2020, 2020
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The state-of-the-science Community Multiscale Air Quality model extended for hemispheric applications (H-CMAQ) is used to model the trans-Pacific transport which has been recognized as a potential source of air pollutants over the US. In Part 2, the higher-order decoupled direct method (HDDM) is applied to investigate the emission impacts from east Asia and the US during April 2010. Furthermore, changes in trans-Pacific transport caused by the recent emissions are examined.
S. Trivikrama Rao, Huiying Luo, Marina Astitha, Christian Hogrefe, Valerie Garcia, and Rohit Mathur
Atmos. Chem. Phys., 20, 1627–1639, https://doi.org/10.5194/acp-20-1627-2020, https://doi.org/10.5194/acp-20-1627-2020, 2020
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Since numerical air quality models do not explicitly simulate stochastic variations in the atmosphere, there will always be differences between modeled and measured pollutant levels even when the model's physics, chemistry, numerical analysis, and its input data are perfect. This paper quantifies the inherent uncertainty in regional models due to the stochastic nature of the atmosphere. A knowledge of the expected error helps model developers in evaluating the real progress in improving models.
Laura M. Judd, Jassim A. Al-Saadi, Scott J. Janz, Matthew G. Kowalewski, R. Bradley Pierce, James J. Szykman, Lukas C. Valin, Robert Swap, Alexander Cede, Moritz Mueller, Martin Tiefengraber, Nader Abuhassan, and David Williams
Atmos. Meas. Tech., 12, 6091–6111, https://doi.org/10.5194/amt-12-6091-2019, https://doi.org/10.5194/amt-12-6091-2019, 2019
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In 2017, an airborne mapping spectrometer (GeoTASO) was used to observe high-resolution column densities of nitrogen dioxide (NO2) over the western shore of Lake Michigan and the Los Angeles Basin. These data were used to simulate the spatial resolution of current and future satellite NO2 retrievals to evaluate the impact of pixel size on comparisons to ground-based observations in urban areas. As spatial resolution improves, the sensitivity to more heterogeneously polluted scenes increases.
Daiwen Kang, Kristen M. Foley, Rohit Mathur, Shawn J. Roselle, Kenneth E. Pickering, and Dale J. Allen
Geosci. Model Dev., 12, 4409–4424, https://doi.org/10.5194/gmd-12-4409-2019, https://doi.org/10.5194/gmd-12-4409-2019, 2019
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This paper provides a comprehensive evaluation of the lightning production schemes in CMAQ as described in https://www.geosci-model-dev.net/12/3071/2019/gmd-12-3071-2019.html on model performance. The impact of lightning NOx from different schemes is evaluated in time and space using both ground–level network measurements and aloft (ozonesonde and aircraft) observations. These results provide users the benchmark model performance when the lightning NOx production schemes are applied.
Daiwen Kang, Kenneth E. Pickering, Dale J. Allen, Kristen M. Foley, David C. Wong, Rohit Mathur, and Shawn J. Roselle
Geosci. Model Dev., 12, 3071–3083, https://doi.org/10.5194/gmd-12-3071-2019, https://doi.org/10.5194/gmd-12-3071-2019, 2019
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Lightning strikes produce significant amount of nitrogen oxides and the resulting atmospheric chemistry causes one of the primary air pollutants, ground-level ozone, to change. In this paper, we documented the evolution of scientific updates for lightning-induced nitrogen oxides schemes in the CMAQ model. The updated observation-based schemes are good for retrospective applications, while the parameterized scheme can estimate lightning nitrogen oxides for applications without observations.
Gabriele Curci, Ummugulsum Alyuz, Rocio Barò, Roberto Bianconi, Johannes Bieser, Jesper H. Christensen, Augustin Colette, Aidan Farrow, Xavier Francis, Pedro Jiménez-Guerrero, Ulas Im, Peng Liu, Astrid Manders, Laura Palacios-Peña, Marje Prank, Luca Pozzoli, Ranjeet Sokhi, Efisio Solazzo, Paolo Tuccella, Alper Unal, Marta G. Vivanco, Christian Hogrefe, and Stefano Galmarini
Atmos. Chem. Phys., 19, 181–204, https://doi.org/10.5194/acp-19-181-2019, https://doi.org/10.5194/acp-19-181-2019, 2019
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Atmospheric carbonaceous aerosols are able to absorb solar radiation and they continue to contribute some of the largest uncertainties in projected climate change. One important detail is how the chemical species are arranged inside each particle, i.e. the knowledge of their mixing state. We use an ensemble of regional model simulations to test different mixing state assumptions and found that a combination of internal and external mixing may better reproduce sunphotometer observations.
Peng Liu, Christian Hogrefe, Ulas Im, Jesper H. Christensen, Johannes Bieser, Uarporn Nopmongcol, Greg Yarwood, Rohit Mathur, Shawn Roselle, and Tanya Spero
Atmos. Chem. Phys., 18, 17157–17175, https://doi.org/10.5194/acp-18-17157-2018, https://doi.org/10.5194/acp-18-17157-2018, 2018
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This study represents an intercomparison of four regional-scale air quality simulations in order to understand the model similarities and differences in estimating the impact of ozone imported from outside of the US on the surface ozone within the US at process level. Vertical turbulent mixing stands out as a primary contributor to the model differences in inert tracers.
Yuqiang Zhang, J. Jason West, Rohit Mathur, Jia Xing, Christian Hogrefe, Shawn J. Roselle, Jesse O. Bash, Jonathan E. Pleim, Chuen-Meei Gan, and David C. Wong
Atmos. Chem. Phys., 18, 15003–15016, https://doi.org/10.5194/acp-18-15003-2018, https://doi.org/10.5194/acp-18-15003-2018, 2018
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Here we use a fine-resolution (36 km) self-consistent 21-year air quality simulation from 1990 to 2010, a health impact function, and annual county-level population and baseline mortality rate estimates to estimate annual mortality burdens from PM2.5 and O3 in the US, and also the contributions to the trends. We found that the PM2.5-related mortality burden has steadily decreased by 53 %, while the O3-related mortality burden has increased by 13 %, with larger inter-annual variabilities.
Marina Astitha, Ioannis Kioutsioukis, Ghezae Araya Fisseha, Roberto Bianconi, Johannes Bieser, Jesper H. Christensen, Owen R. Cooper, Stefano Galmarini, Christian Hogrefe, Ulas Im, Bryan Johnson, Peng Liu, Uarporn Nopmongcol, Irina Petropavlovskikh, Efisio Solazzo, David W. Tarasick, and Greg Yarwood
Atmos. Chem. Phys., 18, 13925–13945, https://doi.org/10.5194/acp-18-13925-2018, https://doi.org/10.5194/acp-18-13925-2018, 2018
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This work is unique in the detailed analyses of modeled ozone vertical profiles from sites in North America through the collaboration of four research groups from the US and EU. We assess the air quality models' performance and model inter-comparison for ozone vertical profiles and stratospheric ozone intrusions. Lastly, we designate the important role of lateral boundary conditions in the ozone vertical profiles using chemically inert tracers.
Mariel D. Friberg, Ralph A. Kahn, James A. Limbacher, K. Wyat Appel, and James A. Mulholland
Atmos. Chem. Phys., 18, 12891–12913, https://doi.org/10.5194/acp-18-12891-2018, https://doi.org/10.5194/acp-18-12891-2018, 2018
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Advances in satellite retrieval of aerosol type can improve ambient air quality concentration estimates by providing regional context where surface monitors are scarce or absent. This work focuses on the degree to which regional-scale satellite and model data can be combined to improve surface estimates of fine particles and their major speciated components. The physically based method applies satellite-derived column observations directly to total and speciated surface particle concentrations.
Elena Spinei, Andrew Whitehill, Alan Fried, Martin Tiefengraber, Travis N. Knepp, Scott Herndon, Jay R. Herman, Moritz Müller, Nader Abuhassan, Alexander Cede, Dirk Richter, James Walega, James Crawford, James Szykman, Lukas Valin, David J. Williams, Russell Long, Robert J. Swap, Youngjae Lee, Nabil Nowak, and Brett Poche
Atmos. Meas. Tech., 11, 4943–4961, https://doi.org/10.5194/amt-11-4943-2018, https://doi.org/10.5194/amt-11-4943-2018, 2018
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Formaldehyde is toxic to humans and is formed in the atmosphere in the presence of air pollution, but the measurements are sparse. Pandonia Global Network instruments measure total formaldehyde column from the surface to the top of troposphere and will be widely available. This study compared formaldehyde Pandora columns with the surface and aircraft-integrated columns near Seoul, South Korea. Relatively good agreement was observed between the three datasets with some overestimation by Pandora.
Marta G. Vivanco, Mark R. Theobald, Héctor García-Gómez, Juan Luis Garrido, Marje Prank, Wenche Aas, Mario Adani, Ummugulsum Alyuz, Camilla Andersson, Roberto Bellasio, Bertrand Bessagnet, Roberto Bianconi, Johannes Bieser, Jørgen Brandt, Gino Briganti, Andrea Cappelletti, Gabriele Curci, Jesper H. Christensen, Augustin Colette, Florian Couvidat, Cornelis Cuvelier, Massimo D'Isidoro, Johannes Flemming, Andrea Fraser, Camilla Geels, Kaj M. Hansen, Christian Hogrefe, Ulas Im, Oriol Jorba, Nutthida Kitwiroon, Astrid Manders, Mihaela Mircea, Noelia Otero, Maria-Teresa Pay, Luca Pozzoli, Efisio Solazzo, Svetlana Tsyro, Alper Unal, Peter Wind, and Stefano Galmarini
Atmos. Chem. Phys., 18, 10199–10218, https://doi.org/10.5194/acp-18-10199-2018, https://doi.org/10.5194/acp-18-10199-2018, 2018
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European wet and dry atmospheric deposition of N and S estimated by 14 air quality models was found to vary substantially. An ensemble of models meeting acceptability criteria was used to estimate the exceedances of the critical loads for N in habitats within the Natura 2000 network, as well as their lower and upper limits. Scenarios with 20 % emission reductions in different regions of the world showed that European emissions are responsible for most of the N and S deposition in Europe.
Ulas Im, Jesper Heile Christensen, Camilla Geels, Kaj Mantzius Hansen, Jørgen Brandt, Efisio Solazzo, Ummugulsum Alyuz, Alessandra Balzarini, Rocio Baro, Roberto Bellasio, Roberto Bianconi, Johannes Bieser, Augustin Colette, Gabriele Curci, Aidan Farrow, Johannes Flemming, Andrea Fraser, Pedro Jimenez-Guerrero, Nutthida Kitwiroon, Peng Liu, Uarporn Nopmongcol, Laura Palacios-Peña, Guido Pirovano, Luca Pozzoli, Marje Prank, Rebecca Rose, Ranjeet Sokhi, Paolo Tuccella, Alper Unal, Marta G. Vivanco, Greg Yarwood, Christian Hogrefe, and Stefano Galmarini
Atmos. Chem. Phys., 18, 8929–8952, https://doi.org/10.5194/acp-18-8929-2018, https://doi.org/10.5194/acp-18-8929-2018, 2018
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We evaluate the impact of global and regional anthropogenic emission reductions on major air pollutant levels over Europe and North America, using a multi-model ensemble of regional chemistry and transport models. Results show that ozone levels are largely driven by long-range transport over both continents while other pollutants such as carbon monoxide or aerosols are mainly controlled by domestic sources. Use of multi-model ensembles can help to reduce the uncertainties in individual models.
Yuqiang Zhang, Rohit Mathur, Jesse O. Bash, Christian Hogrefe, Jia Xing, and Shawn J. Roselle
Atmos. Chem. Phys., 18, 9091–9106, https://doi.org/10.5194/acp-18-9091-2018, https://doi.org/10.5194/acp-18-9091-2018, 2018
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For this study, we evaluated the WRF–CMAQ coupled model's ability to simulate the long-term trends of wet deposition of nitrogen and sulfur from 1990 to 2010 by comparing the model results with long-term observation datasets in the US. The model generally underestimates the wet deposition of both nitrogen and sulfur but captured well the decreasing trends for the deposition. Then we estimated the deposition budget in the US, including wet deposition and dry deposition from model simulations.
Ulas Im, Jørgen Brandt, Camilla Geels, Kaj Mantzius Hansen, Jesper Heile Christensen, Mikael Skou Andersen, Efisio Solazzo, Ioannis Kioutsioukis, Ummugulsum Alyuz, Alessandra Balzarini, Rocio Baro, Roberto Bellasio, Roberto Bianconi, Johannes Bieser, Augustin Colette, Gabriele Curci, Aidan Farrow, Johannes Flemming, Andrea Fraser, Pedro Jimenez-Guerrero, Nutthida Kitwiroon, Ciao-Kai Liang, Uarporn Nopmongcol, Guido Pirovano, Luca Pozzoli, Marje Prank, Rebecca Rose, Ranjeet Sokhi, Paolo Tuccella, Alper Unal, Marta Garcia Vivanco, Jason West, Greg Yarwood, Christian Hogrefe, and Stefano Galmarini
Atmos. Chem. Phys., 18, 5967–5989, https://doi.org/10.5194/acp-18-5967-2018, https://doi.org/10.5194/acp-18-5967-2018, 2018
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The impacts of air pollution on human health and their costs in Europe and the United States for the year 2010 ared modeled by a multi-model ensemble. In Europe, the number of premature deaths is calculated to be 414 000, while in the US it is estimated to be 160 000. Health impacts estimated by individual models can vary up to a factor of 3. Results show that the domestic emissions have the largest impact on premature deaths, compared to foreign sources.
Christian Hogrefe, Peng Liu, George Pouliot, Rohit Mathur, Shawn Roselle, Johannes Flemming, Meiyun Lin, and Rokjin J. Park
Atmos. Chem. Phys., 18, 3839–3864, https://doi.org/10.5194/acp-18-3839-2018, https://doi.org/10.5194/acp-18-3839-2018, 2018
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This study quantifies the impacts of different representations of background ozone in state-of-the-science large-scale models on surface and aloft ozone burdens simulated by the CMAQ regional model over the United States. It also compares both the CMAQ simulations and the driving large-scale models to surface and upper air observations.
Havala O. T. Pye, Andreas Zuend, Juliane L. Fry, Gabriel Isaacman-VanWertz, Shannon L. Capps, K. Wyat Appel, Hosein Foroutan, Lu Xu, Nga L. Ng, and Allen H. Goldstein
Atmos. Chem. Phys., 18, 357–370, https://doi.org/10.5194/acp-18-357-2018, https://doi.org/10.5194/acp-18-357-2018, 2018
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Thermodynamic modeling revealed that some but not all measurements of ammonium-to-sulfate ratios are consistent with theory. The measurement diversity likely explains the previously reported range of results regarding the suitability of thermodynamic modeling. Despite particles being predominantly phase separated, organic–inorganic interactions resulted in increased aerosol pH and partitioning towards the particle phase for highly oxygenated organic compounds compared to traditional methods.
Rohit Mathur, Jia Xing, Robert Gilliam, Golam Sarwar, Christian Hogrefe, Jonathan Pleim, George Pouliot, Shawn Roselle, Tanya L. Spero, David C. Wong, and Jeffrey Young
Atmos. Chem. Phys., 17, 12449–12474, https://doi.org/10.5194/acp-17-12449-2017, https://doi.org/10.5194/acp-17-12449-2017, 2017
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We extend CMAQ's applicability to the entire Northern Hemisphere to enable consistent examination of interactions between atmospheric processes occurring on various spatial and temporal scales. Improvements were made in model process representation, structure, and input data sets that enable a range of model applications including episodic intercontinental pollutant transport, long-term trends in air pollution across the Northern Hemisphere, and air pollution–climate interactions.
Efisio Solazzo, Christian Hogrefe, Augustin Colette, Marta Garcia-Vivanco, and Stefano Galmarini
Atmos. Chem. Phys., 17, 10435–10465, https://doi.org/10.5194/acp-17-10435-2017, https://doi.org/10.5194/acp-17-10435-2017, 2017
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The work here is conducted within the frame of AQMEII3 and promotes the use of diagnostic methods for the evaluation of air quality models. We highlight the need to move away from aggregated error metrics and to focus on the quality of the information that can be extracted from the model and the observation. This aids the understanding of the causes of model error, providing more useful information to model developers and users than can be gained from common evaluations.
Jia Xing, Jiandong Wang, Rohit Mathur, Shuxiao Wang, Golam Sarwar, Jonathan Pleim, Christian Hogrefe, Yuqiang Zhang, Jingkun Jiang, David C. Wong, and Jiming Hao
Atmos. Chem. Phys., 17, 9869–9883, https://doi.org/10.5194/acp-17-9869-2017, https://doi.org/10.5194/acp-17-9869-2017, 2017
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The assessment of the impacts of aerosol direct effects (ADE) is important for understanding emission reduction strategies that seek co-benefits associated with reductions in both particulate matter and ozone. This study quantifies the ADE impacts on tropospheric ozone by using a two-way coupled meteorology and atmospheric chemistry model. Results suggest that reducing ADE may have the potential risk of increasing ozone in winter, but it will benefit the reduction of maxima ozone in summer.
K. Wyat Appel, Sergey L. Napelenok, Kristen M. Foley, Havala O. T. Pye, Christian Hogrefe, Deborah J. Luecken, Jesse O. Bash, Shawn J. Roselle, Jonathan E. Pleim, Hosein Foroutan, William T. Hutzell, George A. Pouliot, Golam Sarwar, Kathleen M. Fahey, Brett Gantt, Robert C. Gilliam, Nicholas K. Heath, Daiwen Kang, Rohit Mathur, Donna B. Schwede, Tanya L. Spero, David C. Wong, and Jeffrey O. Young
Geosci. Model Dev., 10, 1703–1732, https://doi.org/10.5194/gmd-10-1703-2017, https://doi.org/10.5194/gmd-10-1703-2017, 2017
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The Community Multiscale Air Quality (CMAQ) model is a comprehensive multipollutant air quality modeling system. The CMAQ model is used extensively throughout the world to simulate air pollutants for many purposes, including regulatory and air quality forecasting applications. This work describes the scientific updates made to the latest version of the CMAQ modeling system (CMAQv5.1) and presents an evaluation of the new model against observations and results from the previous model version.
Kathleen M. Fahey, Annmarie G. Carlton, Havala O. T. Pye, Jaemeen Baek, William T. Hutzell, Charles O. Stanier, Kirk R. Baker, K. Wyat Appel, Mohammed Jaoui, and John H. Offenberg
Geosci. Model Dev., 10, 1587–1605, https://doi.org/10.5194/gmd-10-1587-2017, https://doi.org/10.5194/gmd-10-1587-2017, 2017
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Chemical transport models (CTMs) are a crucial tool in understanding links between emissions, air quality, and climate. Only a simple description of cloud chemistry has been implemented in many of these; however, clouds play a major role in the physicochemical processing of atmospheric species. In CMAQ, EPA’s widely used CTM, the cloud code is limited to the treatment of simple chemistry. We update CMAQ clouds to consider additional chemistry and then examine regional impacts of these updates.
Meiyun Lin, Larry W. Horowitz, Richard Payton, Arlene M. Fiore, and Gail Tonnesen
Atmos. Chem. Phys., 17, 2943–2970, https://doi.org/10.5194/acp-17-2943-2017, https://doi.org/10.5194/acp-17-2943-2017, 2017
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US ozone pollution responds to varying global-to-regional precursor emissions and climate, with implications for designing effective air quality control policies. Asian anthropogenic emissions of ozone precursors tripled since 1990, contributing 65 % to western US ozone increases in spring, outpacing ozone decreases attained via 50 % US emission controls. In the eastern US, if emissions had not declined, more frequent hot extremes since 1990 would have worsened the highest ozone events in summer.
Efisio Solazzo, Roberto Bianconi, Christian Hogrefe, Gabriele Curci, Paolo Tuccella, Ummugulsum Alyuz, Alessandra Balzarini, Rocío Baró, Roberto Bellasio, Johannes Bieser, Jørgen Brandt, Jesper H. Christensen, Augistin Colette, Xavier Francis, Andrea Fraser, Marta Garcia Vivanco, Pedro Jiménez-Guerrero, Ulas Im, Astrid Manders, Uarporn Nopmongcol, Nutthida Kitwiroon, Guido Pirovano, Luca Pozzoli, Marje Prank, Ranjeet S. Sokhi, Alper Unal, Greg Yarwood, and Stefano Galmarini
Atmos. Chem. Phys., 17, 3001–3054, https://doi.org/10.5194/acp-17-3001-2017, https://doi.org/10.5194/acp-17-3001-2017, 2017
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As part of the third phase of AQMEII, this study uses timescale analysis to apportion error to the responsible processes, detect causes of model error, and identify the processes and scales that require dedicated investigations. The analysis tackles model performance gauging through measurement-to-model comparison, error decomposition, and time series analysis of model biases for ozone, CO, SO2, NO, NO2, PM10, PM2.5, wind speed, and temperature over Europe and North America.
Stefano Galmarini, Brigitte Koffi, Efisio Solazzo, Terry Keating, Christian Hogrefe, Michael Schulz, Anna Benedictow, Jan Jurgen Griesfeller, Greet Janssens-Maenhout, Greg Carmichael, Joshua Fu, and Frank Dentener
Atmos. Chem. Phys., 17, 1543–1555, https://doi.org/10.5194/acp-17-1543-2017, https://doi.org/10.5194/acp-17-1543-2017, 2017
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We present an overview of the coordinated global numerical modelling experiments performed during 2012–2016 by the Task Force on Hemispheric Transport of Air Pollution (TF HTAP), the regional experiments by the Air Quality Model Evaluation International Initiative (AQMEII) over Europe and North America, and the Model Intercomparison Study for Asia (MICS-Asia). Given the organizational complexity of bringing together these three initiatives, the experiment organization is presented.
Havala O. T. Pye, Benjamin N. Murphy, Lu Xu, Nga L. Ng, Annmarie G. Carlton, Hongyu Guo, Rodney Weber, Petros Vasilakos, K. Wyat Appel, Sri Hapsari Budisulistiorini, Jason D. Surratt, Athanasios Nenes, Weiwei Hu, Jose L. Jimenez, Gabriel Isaacman-VanWertz, Pawel K. Misztal, and Allen H. Goldstein
Atmos. Chem. Phys., 17, 343–369, https://doi.org/10.5194/acp-17-343-2017, https://doi.org/10.5194/acp-17-343-2017, 2017
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We use a chemical transport model to examine how organic compounds in the atmosphere interact with water present in particles. Organic compounds themselves lead to water uptake, and organic compounds interact with water associated with inorganic compounds in the rural southeast atmosphere. Including interactions of organic compounds with water requires a treatment of nonideality to more accurately represent aerosol observations during the Southern Oxidant and Aerosol Study (SOAS) 2013.
Ioannis Kioutsioukis, Ulas Im, Efisio Solazzo, Roberto Bianconi, Alba Badia, Alessandra Balzarini, Rocío Baró, Roberto Bellasio, Dominik Brunner, Charles Chemel, Gabriele Curci, Hugo Denier van der Gon, Johannes Flemming, Renate Forkel, Lea Giordano, Pedro Jiménez-Guerrero, Marcus Hirtl, Oriol Jorba, Astrid Manders-Groot, Lucy Neal, Juan L. Pérez, Guidio Pirovano, Roberto San Jose, Nicholas Savage, Wolfram Schroder, Ranjeet S. Sokhi, Dimiter Syrakov, Paolo Tuccella, Johannes Werhahn, Ralf Wolke, Christian Hogrefe, and Stefano Galmarini
Atmos. Chem. Phys., 16, 15629–15652, https://doi.org/10.5194/acp-16-15629-2016, https://doi.org/10.5194/acp-16-15629-2016, 2016
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Four ensemble methods are applied to two annual AQMEII datasets and their performance is compared for O3, NO2 and PM10. The goal of the study is to quantify to what extent we can extract predictable signals from an ensemble with superior skill at each station over the single models and the ensemble mean. The promotion of the right amount of accuracy and diversity within the ensemble results in an average additional skill of up to 31 % compared to using the full ensemble in an unconditional way.
Jia Xing, Rohit Mathur, Jonathan Pleim, Christian Hogrefe, Jiandong Wang, Chuen-Meei Gan, Golam Sarwar, David C. Wong, and Stuart McKeen
Atmos. Chem. Phys., 16, 10865–10877, https://doi.org/10.5194/acp-16-10865-2016, https://doi.org/10.5194/acp-16-10865-2016, 2016
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Downward transport of ozone from the stratosphere has large impacts on surface concentration and needs to be properly represented in regional models. This study developed a seasonally and spatially varying PV-based function from an investigation of the relationship between PV and O3. The implementation of the new function significantly improves the model's performance in O3 simulation, which enables a more accurate simulation of the vertical distribution of O3 across the Northern Hemisphere.
Giulia Ruggeri, Fabian A. Bernhard, Barron H. Henderson, and Satoshi Takahama
Atmos. Chem. Phys., 16, 8729–8747, https://doi.org/10.5194/acp-16-8729-2016, https://doi.org/10.5194/acp-16-8729-2016, 2016
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Functional groups provide an intermediate level of chemical resolution between full molecular speciation and elemental composition for describing complex mixtures and can be a useful metric in model–measurement comparison of reaction kinetics and secondary organic aerosol formation. We introduce tools to facilitate such comparisons and demonstrate its application in study of the photooxidation of two precursor volatile organic compounds and the gas–particle partitioning of their products.
C.-M. Gan, J. Pleim, R. Mathur, C. Hogrefe, C. N. Long, J. Xing, D. Wong, R. Gilliam, and C. Wei
Atmos. Chem. Phys., 15, 12193–12209, https://doi.org/10.5194/acp-15-12193-2015, https://doi.org/10.5194/acp-15-12193-2015, 2015
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This study attempts to determine the consequences of the changes in tropospheric aerosol burden arising from substantial reductions in emissions of SO2 and NOx associated with control measures under the Clean Air Act especially on trends in solar radiation. Comparisons of model results with observations of aerosol optical depth, aerosol concentration, and radiation demonstrate that the coupled WRF-CMAQ model is capable of replicating the trends well even though it tends to underestimate the AOD.
Y. Zhou, H. Mao, K. Demerjian, C. Hogrefe, and J. Liu
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-27253-2015, https://doi.org/10.5194/acpd-15-27253-2015, 2015
Revised manuscript not accepted
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Baseline carbon monoxide (CO) and ozone (O3) were studied at seven rural sites in the Northeast U.S. during varying periods over 2001 – 2010. Baseline CO at all sites decreased significantly at a rate between -4.3 – -2.3 ppbv yr-1, while baseline O3 was relatively constant. Interannual and seasonal variations of baseline CO and O3 were related to increasing Asian emissions, NOx emissions reduction in urban areas, global biomass burning emissions, and meteorological conditions.
C. G. Nolte, K. W. Appel, J. T. Kelly, P. V. Bhave, K. M. Fahey, J. L. Collett Jr., L. Zhang, and J. O. Young
Geosci. Model Dev., 8, 2877–2892, https://doi.org/10.5194/gmd-8-2877-2015, https://doi.org/10.5194/gmd-8-2877-2015, 2015
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This study is the most comprehensive evaluation of CMAQ inorganic
aerosol size-composition distributions conducted to date. We compare two
methods of inferring PM2.5 concentrations from the model: (1) based on
the sum of the masses in the fine aerosol modes, as is most commonly
done in CMAQ model evaluation; and (2) computed using the simulated size
distributions. Differences are generally less than 1 microgram/m3, and
are largest over the eastern USA during the summer.
J. Xing, R. Mathur, J. Pleim, C. Hogrefe, C.-M. Gan, D. C. Wong, and C. Wei
Atmos. Chem. Phys., 15, 9997–10018, https://doi.org/10.5194/acp-15-9997-2015, https://doi.org/10.5194/acp-15-9997-2015, 2015
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The ability of a coupled meteorology-chemistry model (WRF-CMAQ) to reproduce the historical trend in AOD and clear-sky SWR over the N. Hemisphere has been evaluated through a comparison of 21-year simulated results with observation-derived records from 1990 to 2010. Questions of how well the model represents the regional and temporal variability of aerosol burden and DRE, and whether the model is able to capture past trends in aerosol loading and associated radiation effects, will be addressed.
K. M. Seltzer, W. Vizuete, and B. H. Henderson
Atmos. Chem. Phys., 15, 5973–5986, https://doi.org/10.5194/acp-15-5973-2015, https://doi.org/10.5194/acp-15-5973-2015, 2015
J. Xing, R. Mathur, J. Pleim, C. Hogrefe, C.-M. Gan, D. C. Wong, C. Wei, R. Gilliam, and G. Pouliot
Atmos. Chem. Phys., 15, 2723–2747, https://doi.org/10.5194/acp-15-2723-2015, https://doi.org/10.5194/acp-15-2723-2015, 2015
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Model-simulated air quality trends over the past 2 decades largely agree with those derived from observations. In the relative amounts of VOC and NOx emission controls in different regions across the northern hemisphere have led to significantly different trends in tropospheric O3. Differences in the historical changes in the relative amounts of NH3, NOx and SO2 emissions also impact the trends in inorganic particulate matter amounts and composition in China, the U.S. and Europe.
W. Tang, D. S. Cohan, A. Pour-Biazar, L. N. Lamsal, A. T. White, X. Xiao, W. Zhou, B. H. Henderson, and B. F. Lash
Atmos. Chem. Phys., 15, 1601–1619, https://doi.org/10.5194/acp-15-1601-2015, https://doi.org/10.5194/acp-15-1601-2015, 2015
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A joint application of multiple satellite-derived model inputs to improve Texas O3 SIP modeling is demonstrated in this study. The GOES-retrieved clouds are applied to correct the modeled photolysis rates, and the DKF inversion approach is incorporated into the CAMx-DDM model to adjust NOx emissions using OMI NO2. Using both GOES-derived photolysis rates and OMI-constrained NOx emissions together improves O3 simulations and makes O3 more sensitive to NOx emissions in the O3 non-attainment areas.
R. H. F. Kwok, K. R. Baker, S. L. Napelenok, and G. S. Tonnesen
Geosci. Model Dev., 8, 99–114, https://doi.org/10.5194/gmd-8-99-2015, https://doi.org/10.5194/gmd-8-99-2015, 2015
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The implementation and application of the Integrated Source Apportionment Method (ISAM) for O3 and its precursors for the Community Multiscale Air Quality (CMAQ) model are described. CMAQ-ISAM is a hybrid of source apportionment and source sensitivity in that O3 production is attributed to precursor sources based on the O3 formation regime. CMAQ-ISAM offers a source attribution tool for the purposes of quantifying and understanding sources and impacts of regional air pollution.
C.-M. Gan, J. Pleim, R. Mathur, C. Hogrefe, C. N. Long, J. Xing, S. Roselle, and C. Wei
Atmos. Chem. Phys., 14, 1701–1715, https://doi.org/10.5194/acp-14-1701-2014, https://doi.org/10.5194/acp-14-1701-2014, 2014
J. Xing, J. Pleim, R. Mathur, G. Pouliot, C. Hogrefe, C.-M. Gan, and C. Wei
Atmos. Chem. Phys., 13, 7531–7549, https://doi.org/10.5194/acp-13-7531-2013, https://doi.org/10.5194/acp-13-7531-2013, 2013
K. W. Appel, G. A. Pouliot, H. Simon, G. Sarwar, H. O. T. Pye, S. L. Napelenok, F. Akhtar, and S. J. Roselle
Geosci. Model Dev., 6, 883–899, https://doi.org/10.5194/gmd-6-883-2013, https://doi.org/10.5194/gmd-6-883-2013, 2013
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Why did ozone concentrations remain high during Shanghai's static management? A statistical and radical-chemistry perspective
Revising VOC emissions speciation improves the simulation of global background ethane and propane
Changes in South American surface ozone trends: exploring the influences of precursors and extreme events
Evaluating NOx stack plume emissions using a high-resolution atmospheric chemistry model and satellite-derived NO2 columns
NOx emissions in France in 2019–2021 as estimated by the high-spatial-resolution assimilation of TROPOMI NO2 observations
Aggravated surface O3 pollution primarily driven by meteorological variations in China during the 2020 COVID-19 pandemic lockdown period
Identifying decadal trends in deweathered concentrations of criteria air pollutants in Canadian urban atmospheres with machine learning approaches
Evaluation of modelled versus observed non-methane volatile organic compounds at European Monitoring and Evaluation Programme sites in Europe
Constraining non-methane VOC emissions with TROPOMI HCHO observations: impact on summertime ozone simulation in August 2022 in China
Revealing the significant acceleration of hydrofluorocarbon (HFC) emissions in eastern Asia through long-term atmospheric observations
Interpreting Geostationary Environment Monitoring Spectrometer (GEMS) geostationary satellite observations of the diurnal variation in nitrogen dioxide (NO2) over East Asia
An intercomparison of satellite, airborne, and ground-level observations with WRF–CAMx simulations of NO2 columns over Houston, Texas, during the September 2021 TRACER-AQ campaign
Interannual variability of summertime formaldehyde (HCHO) vertical column density and its main drivers at northern high latitudes
The impact of multi-decadal changes in VOC speciation on urban ozone chemistry: a case study in Birmingham, United Kingdom
Technical note: Challenges in detecting free tropospheric ozone trends in a sparsely sampled environment
Combined assimilation of NOAA surface and MIPAS satellite observations to constrain the global budget of carbonyl sulfide
The impact of gaseous degradation on the gas–particle partitioning of methylated polycyclic aromatic hydrocarbons
Technical note: An assessment of the performance of statistical bias correction techniques for global chemistry–climate model surface ozone fields
A better representation of volatile organic compound chemistry in WRF-Chem and its impact on ozone over Los Angeles
High-resolution US methane emissions inferred from an inversion of 2019 TROPOMI satellite data: contributions from individual states, urban areas, and landfills
Summertime tropospheric ozone source apportionment study in the Madrid region (Spain)
CO anthropogenic emissions in Europe from 2011 to 2021: insights from Measurement of Pollution in the Troposphere (MOPITT) satellite data
Constraining long-term NOx emissions over the United States and Europe using nitrate wet deposition monitoring networks
Analysis of an intense O3 pollution episode on the Atlantic coast of the Iberian Peninsula using photochemical modeling: characterization of transport pathways and accumulation processes
Atmospheric oxygen as a tracer for fossil fuel carbon dioxide: a sensitivity study in the UK
Impact of improved representation of VOC emissions and production of NOx reservoirs on modeled urban ozone production
MIXv2: a long-term mosaic emission inventory for Asia (2010–2017)
Organosulfate produced from consumption of SO3 speeds up sulfuric acid–dimethylamine atmospheric nucleation
Contribution of expanded marine sulfur chemistry to the seasonal variability of dimethyl sulfide oxidation products and size-resolved sulfate aerosol
Development of a detailed gaseous oxidation scheme of naphthalene for SOA formation and speciation
Spatial disparities of ozone pollution in the Sichuan Basin spurred by extreme, hot weather
Global impacts of aviation on air quality evaluated at high resolution
Enhancing Long-Term Trend Simulation of Global Tropospheric OH and Its Drivers from 2005–2019: A Synergistic Integration of Model Simulations and Satellite Observations
Large contribution of soil emissions to the atmospheric nitrogen budget and their impacts on air quality and temperature rise in North China
Bias correction of OMI HCHO columns based on FTIR and aircraft measurements and impact on top-down emission estimates
Intercomparison of GEOS-Chem and CAM-chem tropospheric oxidant chemistry within the Community Earth System Model version 2 (CESM2)
Investigation of the renewed methane growth post-2007 with high-resolution 3-D variational inverse modeling and isotopic constraints
Air quality and radiative impacts of downward-propagating sudden stratospheric warmings (SSWs)
Estimation of the atmospheric hydroxyl radical oxidative capacity using multiple hydrofluorocarbons (HFCs)
Investigating the differences in calculating global mean surface CO2 abundance: the impact of analysis methodologies and site selection
The effect of different Climate and Air Quality policies in China on in situ Ozone production in Beijing
Meteorological characteristics of extreme ozone pollution events in China and their future predictions
Evaluating modelled tropospheric columns of CH4, CO, and O3 in the Arctic using ground-based Fourier transform infrared (FTIR) measurements
The high-resolution Global Aviation emissions Inventory based on ADS-B (GAIA) for 2019–2021
Zonal variability of methane trends derived from satellite data
Weekly derived top-down volatile-organic-compound fluxes over Europe from TROPOMI HCHO data from 2018 to 2021
Current status of model predictions of volatile organic compounds and impacts on surface ozone predictions during summer in China
Utility of Geostationary Lightning Mapper-derived lightning NO emission estimates in air quality modeling studies
The suitability of atmospheric oxygen measurements to constrain western European fossil-fuel CO2 emissions and their trends
Future tropospheric ozone budget and distribution over east Asia under a net-zero scenario
Jian Zhu, Shanshan Wang, Chuanqi Gu, Zhiwen Jiang, Sanbao Zhang, Ruibin Xue, Yuhao Yan, and Bin Zhou
Atmos. Chem. Phys., 24, 8383–8395, https://doi.org/10.5194/acp-24-8383-2024, https://doi.org/10.5194/acp-24-8383-2024, 2024
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In 2022, Shanghai implemented city-wide static management measures during the high-ozone season in April and May, providing a chance to study ozone pollution control. Despite significant emissions reductions, ozone levels increased by 23 %. Statistically, the number of days with higher ozone diurnal variation types increased during the lockdown period. The uneven decline in VOC and NO2 emissions led to heightened photochemical processes, resulting in the observed ozone level rise.
Matthew J. Rowlinson, Mat J. Evans, Lucy J. Carpenter, Katie A. Read, Shalini Punjabi, Adedayo Adedeji, Luke Fakes, Ally Lewis, Ben Richmond, Neil Passant, Tim Murrells, Barron Henderson, Kelvin H. Bates, and Detlev Helmig
Atmos. Chem. Phys., 24, 8317–8342, https://doi.org/10.5194/acp-24-8317-2024, https://doi.org/10.5194/acp-24-8317-2024, 2024
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Ethane and propane are volatile organic compounds emitted from human activities which help to form ozone, a pollutant and greenhouse gas, and also affect the chemistry of the lower atmosphere. Atmospheric models tend to do a poor job of reproducing the abundance of these compounds in the atmosphere. By using regional estimates of their emissions, rather than globally consistent estimates, we can significantly improve the simulation of ethane in the model and make some improvement for propane.
Rodrigo J. Seguel, Lucas Castillo, Charlie Opazo, Néstor Y. Rojas, Thiago Nogueira, María Cazorla, Mario Gavidia-Calderón, Laura Gallardo, René Garreaud, Tomás Carrasco-Escaff, and Yasin Elshorbany
Atmos. Chem. Phys., 24, 8225–8242, https://doi.org/10.5194/acp-24-8225-2024, https://doi.org/10.5194/acp-24-8225-2024, 2024
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Trends of surface ozone were examined across South America. Our findings indicate that ozone trends in major South American cities either increase or remain steady, with no signs of decline. The upward trends can be attributed to chemical regimes that efficiently convert nitric oxide into nitrogen dioxide. Additionally, our results suggest a climate penalty for ozone driven by meteorological conditions that favor wildfire propagation in Chile and extensive heat waves in southern Brazil.
Maarten Krol, Bart van Stratum, Isidora Anglou, and Klaas Folkert Boersma
Atmos. Chem. Phys., 24, 8243–8262, https://doi.org/10.5194/acp-24-8243-2024, https://doi.org/10.5194/acp-24-8243-2024, 2024
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This paper presents detailed plume simulations of nitrogen oxides and carbon dioxide that are emitted from four large industrial facilities world-wide. Results from the high-resolution simulations that include atmospheric chemistry are compared to nitrogen dioxide observations from satellites. We find good performance of the model and show that common assumptions that are used in simplified models need revision. This work is important for the monitoring of emissions using satellite data.
Robin Plauchu, Audrey Fortems-Cheiney, Grégoire Broquet, Isabelle Pison, Antoine Berchet, Elise Potier, Gaëlle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, and Henk Eskes
Atmos. Chem. Phys., 24, 8139–8163, https://doi.org/10.5194/acp-24-8139-2024, https://doi.org/10.5194/acp-24-8139-2024, 2024
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This study uses the Community Inversion Framework and CHIMERE model to assess the potential of TROPOMI-S5P PAL NO2 tropospheric column data to estimate NOx emissions in France (2019–2021). Results show a 3 % decrease in average emissions compared to the 2016 CAMS-REG/INS, lower than the 14 % decrease from CITEPA. The study highlights challenges in capturing emission anomalies due to limited data coverage and error levels but shows promise for local inventory improvements.
Zhendong Lu, Jun Wang, Yi Wang, Daven K. Henze, Xi Chen, Tong Sha, and Kang Sun
Atmos. Chem. Phys., 24, 7793–7813, https://doi.org/10.5194/acp-24-7793-2024, https://doi.org/10.5194/acp-24-7793-2024, 2024
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In contrast with past work showing that the reduction of emissions was the dominant factor for the nationwide increase of surface O3 during the lockdown in China, this study finds that the variation in meteorology (temperature and other parameters) plays a more important role. This result is obtained through sensitivity simulations using a chemical transport model constrained by satellite (TROPOMI) data and calibrated with surface observations.
Xiaohong Yao and Leiming Zhang
Atmos. Chem. Phys., 24, 7773–7791, https://doi.org/10.5194/acp-24-7773-2024, https://doi.org/10.5194/acp-24-7773-2024, 2024
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This study investigates long-term trends of criteria air pollutants, including NO2, CO, SO2, O3 and PM2.5, and NO2+O3 measured in 10 Canadian cities during the last 2 to 3 decades. We also investigate associated driving forces in terms of emission reductions, perturbations from varying weather conditions and large-scale wildfires, as well as changes in O3 sources and sinks.
Yao Ge, Sverre Solberg, Mathew R. Heal, Stefan Reimann, Willem van Caspel, Bryan Hellack, Thérèse Salameh, and David Simpson
Atmos. Chem. Phys., 24, 7699–7729, https://doi.org/10.5194/acp-24-7699-2024, https://doi.org/10.5194/acp-24-7699-2024, 2024
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Atmospheric volatile organic compounds (VOCs) constitute many species, acting as precursors to ozone and aerosol. Given the uncertainties in VOC emissions, lack of evaluation studies, and recent changes in emissions, this work adapts the EMEP MSC-W to evaluate emission inventories in Europe. We focus on the varying agreement between modelled and measured VOCs across different species and underscore potential inaccuracies in total and sector-specific emission estimates.
Shuzhuang Feng, Fei Jiang, Tianlu Qian, Nan Wang, Mengwei Jia, Songci Zheng, Jiansong Chen, Fang Ying, and Weimin Ju
Atmos. Chem. Phys., 24, 7481–7498, https://doi.org/10.5194/acp-24-7481-2024, https://doi.org/10.5194/acp-24-7481-2024, 2024
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We developed a multi-air-pollutant inversion system to estimate non-methane volatile organic compound (NMVOC) emissions using TROPOMI formaldehyde retrievals. We found that the inversion significantly improved formaldehyde simulations and reduced NMVOC emission uncertainties. The optimized NMVOC emissions effectively corrected the overestimation of O3 levels, mainly by decreasing the rate of the RO2 + NO reaction and increasing the rate of the NO2 + OH reaction.
Haklim Choi, Alison L. Redington, Hyeri Park, Jooil Kim, Rona L. Thompson, Jens Mühle, Peter K. Salameh, Christina M. Harth, Ray F. Weiss, Alistair J. Manning, and Sunyoung Park
Atmos. Chem. Phys., 24, 7309–7330, https://doi.org/10.5194/acp-24-7309-2024, https://doi.org/10.5194/acp-24-7309-2024, 2024
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We analyzed with an inversion model the atmospheric abundance of hydrofluorocarbons (HFCs), potent greenhouse gases, from 2008 to 2020 at Gosan station in South Korea and revealed a significant increase in emissions, especially from eastern China and Japan. This increase contradicts reported data, underscoring the need for accurate monitoring and reporting. Our findings are crucial for understanding and managing global HFCs emissions, highlighting the importance of efforts to reduce HFCs.
Laura Hyesung Yang, Daniel J. Jacob, Ruijun Dang, Yujin J. Oak, Haipeng Lin, Jhoon Kim, Shixian Zhai, Nadia K. Colombi, Drew C. Pendergrass, Ellie Beaudry, Viral Shah, Xu Feng, Robert M. Yantosca, Heesung Chong, Junsung Park, Hanlim Lee, Won-Jin Lee, Soontae Kim, Eunhye Kim, Katherine R. Travis, James H. Crawford, and Hong Liao
Atmos. Chem. Phys., 24, 7027–7039, https://doi.org/10.5194/acp-24-7027-2024, https://doi.org/10.5194/acp-24-7027-2024, 2024
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The Geostationary Environment Monitoring Spectrometer (GEMS) provides hourly measurements of NO2. We use the chemical transport model to find how emissions, chemistry, and transport drive the changes in NO2 observed by GEMS at different times of the day. In winter, the chemistry plays a minor role, and high daytime emissions dominate the diurnal variation in NO2, balanced by transport. In summer, emissions, chemistry, and transport play an important role in shaping the diurnal variation in NO2.
M. Omar Nawaz, Jeremiah Johnson, Greg Yarwood, Benjamin de Foy, Laura Judd, and Daniel L. Goldberg
Atmos. Chem. Phys., 24, 6719–6741, https://doi.org/10.5194/acp-24-6719-2024, https://doi.org/10.5194/acp-24-6719-2024, 2024
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NO2 is a gas with implications for air pollution. A campaign conducted in Houston provided an opportunity to compare NO2 from different instruments and a model. Aircraft and satellite observations agreed well with measurements on the ground; however, the latter estimated lower values. We find that model-simulated NO2 was lower than observations, especially downtown, suggesting that NO2 sources associated with the urban core of Houston, such as vehicle emissions, may be underestimated.
Tianlang Zhao, Jingqiu Mao, Zolal Ayazpour, Gonzalo González Abad, Caroline R. Nowlan, and Yiqi Zheng
Atmos. Chem. Phys., 24, 6105–6121, https://doi.org/10.5194/acp-24-6105-2024, https://doi.org/10.5194/acp-24-6105-2024, 2024
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HCHO variability is a key tracer in understanding VOC emissions in response to climate change. We investigate the role of methane oxidation and biogenic and wildfire emissions in HCHO interannual variability over northern high latitudes in summer, emphasizing wildfires as a key driver of HCHO interannual variability in Alaska, Siberia and northern Canada using satellite HCHO and SIF retrievals and then GEOS-Chem model. We show SIF is a tool to understand biogenic HCHO variability in this region.
Jianghao Li, Alastair C. Lewis, Jim R. Hopkins, Stephen J. Andrews, Tim Murrells, Neil Passant, Ben Richmond, Siqi Hou, William J. Bloss, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 24, 6219–6231, https://doi.org/10.5194/acp-24-6219-2024, https://doi.org/10.5194/acp-24-6219-2024, 2024
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A summertime ozone event at an urban site in Birmingham is sensitive to volatile organic compounds (VOCs) – particularly those of oxygenated VOCs. The roles of anthropogenic VOC sources in urban ozone chemistry are examined by integrating the 1990–2019 national atmospheric emission inventory into model scenarios. Road transport remains the most powerful means of further reducing ozone in this case study, but the benefits may be offset if solvent emissions of VOCs continue to increase.
Kai-Lan Chang, Owen R. Cooper, Audrey Gaudel, Irina Petropavlovskikh, Peter Effertz, Gary Morris, and Brian C. McDonald
Atmos. Chem. Phys., 24, 6197–6218, https://doi.org/10.5194/acp-24-6197-2024, https://doi.org/10.5194/acp-24-6197-2024, 2024
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A great majority of observational trend studies of free tropospheric ozone use sparsely sampled ozonesonde and aircraft measurements as reference data sets. A ubiquitous assumption is that trends are accurate and reliable so long as long-term records are available. We show that sampling bias due to sparse samples can persistently reduce the trend accuracy, and we highlight the importance of maintaining adequate frequency and continuity of observations.
Jin Ma, Linda M. J. Kooijmans, Norbert Glatthor, Stephen A. Montzka, Marc von Hobe, Thomas Röckmann, and Maarten C. Krol
Atmos. Chem. Phys., 24, 6047–6070, https://doi.org/10.5194/acp-24-6047-2024, https://doi.org/10.5194/acp-24-6047-2024, 2024
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The global budget of atmospheric COS can be optimised by inverse modelling using TM5-4DVAR, with the co-constraints of NOAA surface observations and MIPAS satellite data. We found reduced COS biosphere uptake from inversions and improved land and ocean separation using MIPAS satellite data assimilation. Further improvements are expected from better quantification of COS ocean and biosphere fluxes.
Fu-Jie Zhu, Zi-Feng Zhang, Li-Yan Liu, Pu-Fei Yang, Peng-Tuan Hu, Geng-Bo Ren, Meng Qin, and Wan-Li Ma
Atmos. Chem. Phys., 24, 6095–6103, https://doi.org/10.5194/acp-24-6095-2024, https://doi.org/10.5194/acp-24-6095-2024, 2024
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Gas–particle (G–P) partitioning is an important atmospheric behavior for semi-volatile organic compounds (SVOCs). Diurnal variation in G–P partitioning of methylated polycyclic aromatic hydrocarbons (Me-PAHs) demonstrates the possible influence of gaseous degradation; the enhancement of gaseous degradation (1.10–5.58 times) on G–P partitioning is verified by a steady-state G–P partitioning model. The effect of gaseous degradation on G–P partitioning of (especially light) SVOCs is important.
Christoph Staehle, Harald E. Rieder, Arlene M. Fiore, and Jordan L. Schnell
Atmos. Chem. Phys., 24, 5953–5969, https://doi.org/10.5194/acp-24-5953-2024, https://doi.org/10.5194/acp-24-5953-2024, 2024
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Chemistry–climate models show biases compared to surface ozone observations and thus require bias correction for impact studies and the assessment of air quality changes. We compare the performance of commonly used correction techniques for model outputs available via CMIP6. While all methods can reduce model biases, better results are obtained from more complex approaches. Thus, our study suggests broader use of these techniques in studies seeking to inform air quality management and policy.
Qindan Zhu, Rebecca H. Schwantes, Matthew Coggon, Colin Harkins, Jordan Schnell, Jian He, Havala O. T. Pye, Meng Li, Barry Baker, Zachary Moon, Ravan Ahmadov, Eva Y. Pfannerstill, Bryan Place, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Anthony Bucholtz, John H. Seinfeld, Carsten Warneke, Chelsea E. Stockwell, Lu Xu, Kristen Zuraski, Michael A. Robinson, J. Andrew Neuman, Patrick R. Veres, Jeff Peischl, Steven S. Brown, Allen H. Goldstein, Ronald C. Cohen, and Brian C. McDonald
Atmos. Chem. Phys., 24, 5265–5286, https://doi.org/10.5194/acp-24-5265-2024, https://doi.org/10.5194/acp-24-5265-2024, 2024
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Volatile organic compounds (VOCs) fuel the production of air pollutants like ozone and particulate matter. The representation of VOC chemistry remains challenging due to its complexity in speciation and reactions. Here, we develop a chemical mechanism, RACM2B-VCP, that better represents VOC chemistry in urban areas such as Los Angeles. We also discuss the contribution of VOCs emitted from volatile chemical products and other anthropogenic sources to total VOC reactivity and O3.
Hannah Nesser, Daniel J. Jacob, Joannes D. Maasakkers, Alba Lorente, Zichong Chen, Xiao Lu, Lu Shen, Zhen Qu, Melissa P. Sulprizio, Margaux Winter, Shuang Ma, A. Anthony Bloom, John R. Worden, Robert N. Stavins, and Cynthia A. Randles
Atmos. Chem. Phys., 24, 5069–5091, https://doi.org/10.5194/acp-24-5069-2024, https://doi.org/10.5194/acp-24-5069-2024, 2024
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We quantify 2019 methane emissions in the contiguous US (CONUS) at a ≈ 25 km × 25 km resolution using satellite methane observations. We find a 13 % upward correction to the 2023 US Environmental Protection Agency (EPA) Greenhouse Gas Emissions Inventory (GHGI) for 2019, with large corrections to individual states, urban areas, and landfills. This may present a challenge for US climate policies and goals, many of which target significant reductions in methane emissions.
David de la Paz, Rafael Borge, Juan Manuel de Andrés, Luis Tovar, Golam Sarwar, and Sergey L. Napelenok
Atmos. Chem. Phys., 24, 4949–4972, https://doi.org/10.5194/acp-24-4949-2024, https://doi.org/10.5194/acp-24-4949-2024, 2024
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This source apportionment modeling study shows that around 70 % of ground-level O3 in Madrid (Spain) is transported from other regions. Nonetheless, emissions from local sources, mainly road traffic, play a significant role, especially under atmospheric stagnation. Local measures during those conditions may be able to reduce O3 peaks by up to 30 % and, thus, lessen impacts from high-O3 episodes in the Madrid metropolitan area.
Audrey Fortems-Cheiney, Gregoire Broquet, Elise Potier, Robin Plauchu, Antoine Berchet, Isabelle Pison, Hugo Denier van der Gon, and Stijn Dellaert
Atmos. Chem. Phys., 24, 4635–4649, https://doi.org/10.5194/acp-24-4635-2024, https://doi.org/10.5194/acp-24-4635-2024, 2024
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We have estimated the carbon monixide (CO) European emissions from satellite observations of the MOPITT instrument at the relatively high resolution of 0.5° for a period of over 10 years from 2011 to 2021. The analysis of the inversion results reveals the challenges associated with the inversion of CO emissions at the regional scale over Europe.
Amy Christiansen, Loretta J. Mickley, and Lu Hu
Atmos. Chem. Phys., 24, 4569–4589, https://doi.org/10.5194/acp-24-4569-2024, https://doi.org/10.5194/acp-24-4569-2024, 2024
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In this work, we provide an additional constraint on emissions and trends of nitrogen oxides using nitrate wet deposition (NWD) fluxes over the United States and Europe from 1980–2020. We find that NWD measurements constrain total NOx emissions well. We also find evidence of NOx emission overestimates in both domains, but especially over Europe, where NOx emissions are overestimated by a factor of 2. Reducing NOx emissions over Europe improves model representation of ozone at the surface.
Eduardo Torre-Pascual, Gotzon Gangoiti, Ana Rodríguez-García, Estibaliz Sáez de Cámara, Joana Ferreira, Carla Gama, María Carmen Gómez, Iñaki Zuazo, Jose Antonio García, and Maite de Blas
Atmos. Chem. Phys., 24, 4305–4329, https://doi.org/10.5194/acp-24-4305-2024, https://doi.org/10.5194/acp-24-4305-2024, 2024
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We present an analysis of an intense air pollution episode of tropospheric ozone (O3) along the Atlantic coast of the Iberian Peninsula, incorporating both measured and simulated parameters. Our study extends beyond surface-level factors to include altitude-related parameters. These episodes stem from upper-atmosphere O3 accumulation in preceding days, transported to surface layers, causing rapid O3 concentration increase.
Hannah Chawner, Eric Saboya, Karina E. Adcock, Tim Arnold, Yuri Artioli, Caroline Dylag, Grant L. Forster, Anita Ganesan, Heather Graven, Gennadi Lessin, Peter Levy, Ingrid T. Luijkx, Alistair Manning, Penelope A. Pickers, Chris Rennick, Christian Rödenbeck, and Matthew Rigby
Atmos. Chem. Phys., 24, 4231–4252, https://doi.org/10.5194/acp-24-4231-2024, https://doi.org/10.5194/acp-24-4231-2024, 2024
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The quantity of atmospheric potential oxygen (APO), derived from coincident measurements of carbon dioxide (CO2) and oxygen (O2), has been proposed as a tracer for fossil fuel CO2 emissions. In this model sensitivity study, we examine the use of APO for this purpose in the UK and compare our model to observations. We find that our model simulations are most sensitive to uncertainties relating to ocean fluxes and boundary conditions.
Katherine R. Travis, Benjamin A. Nault, James H. Crawford, Kelvin H. Bates, Donald R. Blake, Ronald C. Cohen, Alan Fried, Samuel R. Hall, L. Greg Huey, Young Ro Lee, Simone Meinardi, Kyung-Eun Min, Isobel J. Simpson, and Kirk Ullman
EGUsphere, https://doi.org/10.5194/egusphere-2024-951, https://doi.org/10.5194/egusphere-2024-951, 2024
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Human activities result in the emission of many volatile organic compounds (VOCs) into the atmosphere that contribute to ozone air pollution. Detailed measurements were taken of VOCs during a field study in South Korea. When compared to models using current VOC emissions, large discrepancies pointed to underestimated emissions from chemical products, liquified petroleum gas, and long-range transport. We improved emissions and chemistry of these VOCs to better describe urban ozone pollution.
Meng Li, Junichi Kurokawa, Qiang Zhang, Jung-Hun Woo, Tazuko Morikawa, Satoru Chatani, Zifeng Lu, Yu Song, Guannan Geng, Hanwen Hu, Jinseok Kim, Owen R. Cooper, and Brian C. McDonald
Atmos. Chem. Phys., 24, 3925–3952, https://doi.org/10.5194/acp-24-3925-2024, https://doi.org/10.5194/acp-24-3925-2024, 2024
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In this work, we developed MIXv2, a mosaic Asian emission inventory for 2010–2017. With high spatial (0.1°) and monthly temporal resolution, MIXv2 integrates anthropogenic and open biomass burning emissions across seven sectors following a mosaic methodology. It provides CO2 emissions data alongside nine key pollutants and three chemical mechanisms. Our publicly accessible gridded monthly emissions data can facilitate long-term atmospheric and climate model analyses.
Xiaomeng Zhang, Yongjian Lian, Shendong Tan, and Shi Yin
Atmos. Chem. Phys., 24, 3593–3612, https://doi.org/10.5194/acp-24-3593-2024, https://doi.org/10.5194/acp-24-3593-2024, 2024
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Atmospheric new particle formation (NPF) has a significant influence on the global climate, local air quality and human health. Using a combination of quantum chemical calculations and kinetics modeling, we find that thhe gas-phase organosulfate produced from consumption of SO3 can significantly enhance SA–DMA nucleation in the polluted boundary layer, resulting in non-negligible contributions to NPF. Our findings provide important insights into organic sulfur in atmospheric aerosol formation.
Linia Tashmim, William C. Porter, Qianjie Chen, Becky Alexander, Charles H. Fite, Christopher D. Holmes, Jeffrey R. Pierce, Betty Croft, and Sakiko Ishino
Atmos. Chem. Phys., 24, 3379–3403, https://doi.org/10.5194/acp-24-3379-2024, https://doi.org/10.5194/acp-24-3379-2024, 2024
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Dimethyl sulfide (DMS) is mostly emitted from ocean surfaces and represents the largest natural source of sulfur for the atmosphere. Once in the atmosphere, DMS forms stable oxidation products such as SO2 and H2SO4, which can subsequently contribute to airborne particle formation and growth. In this study, we update the DMS oxidation mechanism in the chemical transport model GEOS-Chem and describe resulting changes in particle growth as well as the overall global sulfur budget.
Victor Lannuque and Karine Sartelet
EGUsphere, https://doi.org/10.5194/egusphere-2024-711, https://doi.org/10.5194/egusphere-2024-711, 2024
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Large uncertainties remain in understanding secondary organic aerosol (SOA) formation and speciation from naphthalene oxidation. This study details the development of the first near-explicit chemical scheme for naphthalene oxidation by OH including kinetic and mechanistic data and able to reproduce most of the experimentally identified products in both gas and particle phases.
Nan Wang, Yunsong Du, Dongyang Chen, Haiyan Meng, Xi Chen, Li Zhou, Guangming Shi, Yu Zhan, Miao Feng, Wei Li, Mulan Chen, Zhenliang Li, and Fumo Yang
Atmos. Chem. Phys., 24, 3029–3042, https://doi.org/10.5194/acp-24-3029-2024, https://doi.org/10.5194/acp-24-3029-2024, 2024
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In the scorching August 2022 heatwave, China's Sichuan Basin saw a stark contrast in ozone (O3) levels between Chengdu and Chongqing. The regional disparities were studied considering meteorology, precursors, photochemistry, and transportation. The study highlighted the importance of tailored pollution control measures and underlined the necessity for region-specific strategies to combat O3 pollution on a regional scale.
Sebastian D. Eastham, Guillaume P. Chossière, Raymond L. Speth, Daniel J. Jacob, and Steven R. H. Barrett
Atmos. Chem. Phys., 24, 2687–2703, https://doi.org/10.5194/acp-24-2687-2024, https://doi.org/10.5194/acp-24-2687-2024, 2024
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Emissions from aircraft are known to cause air quality impacts worldwide, but the scale and mechanisms of this impact are not well understood. This work uses high-resolution computational modeling of the atmosphere to show that air pollution changes from aviation are mostly the result of emissions during cruise (high-altitude) operations, that these impacts are related to how much non-aviation pollution is present, and that prior regional assessments have underestimated these impacts.
Amir H. Souri, Bryan N. Duncan, Sarah A. Strode, Daniel C. Anderson, Michael E. Manyin, Junhua Liu, Luke D. Oman, Zhen Zhang, and Brad Weir
EGUsphere, https://doi.org/10.5194/egusphere-2024-410, https://doi.org/10.5194/egusphere-2024-410, 2024
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We explore a new method to make use of the wealth of information obtained from satellite observations of Aura OMI NO2, HCHO, along with MERRA2 reanalysis in NASA’s GEOS model equipped with an efficient tropospheric OH (TOH) estimator to enhance the representation of TOH spatial distribution and its long-term trends. This new framework helps us pinpoint regional inaccuracies in TOH and differentiate between established prior knowledge and newly acquired information from satellites on TOH trends.
Tong Sha, Siyu Yang, Qingcai Chen, Liangqing Li, Xiaoyan Ma, Yan-Lin Zhang, Zhaozhong Feng, K. Folkert Boersma, and Jun Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-359, https://doi.org/10.5194/egusphere-2024-359, 2024
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By using an updated soil reactive nitrogen emission scheme in the UI-WRF-Chem model, we investigate the underappreciated role of soil NO and HONO (Nr) emissions on air quality and temperature rise in North China. The significant contributions of soil Nr emissions to O3 and secondary pollutants, exceeding the effects of soil NOx or HONO emission alone. And soil Nr emissions play an important role in mitigating O3 pollution and addressing climate change.
Jean-François Müller, Trissevgeni Stavrakou, Glenn-Michael Oomen, Beata Opacka, Isabelle De Smedt, Alex Guenther, Corinne Vigouroux, Bavo Langerock, Carlos Augusto Bauer Aquino, Michel Grutter, James Hannigan, Frank Hase, Rigel Kivi, Erik Lutsch, Emmanuel Mahieu, Maria Makarova, Jean-Marc Metzger, Isamu Morino, Isao Murata, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Amelie Röhling, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, and Alan Fried
Atmos. Chem. Phys., 24, 2207–2237, https://doi.org/10.5194/acp-24-2207-2024, https://doi.org/10.5194/acp-24-2207-2024, 2024
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Formaldehyde observations from satellites can be used to constrain the emissions of volatile organic compounds, but those observations have biases. Using an atmospheric model, aircraft and ground-based remote sensing data, we quantify these biases, propose a correction to the data, and assess the consequence of this correction for the evaluation of emissions.
Haipeng Lin, Louisa K. Emmons, Elizabeth W. Lundgren, Laura Hyesung Yang, Xu Feng, Ruijun Dang, Shixian Zhai, Yunxiao Tang, Makoto M. Kelp, Nadia K. Colombi, Sebastian D. Eastham, Thibaud M. Fritz, and Daniel J. Jacob
EGUsphere, https://doi.org/10.5194/egusphere-2024-470, https://doi.org/10.5194/egusphere-2024-470, 2024
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Tropospheric ozone is a major air pollutant, greenhouse gas, and a major indicator of model skill. Global atmospheric chemistry models show large differences in simulations of tropospheric ozone but isolating sources of differences is complicated by different model environments. By implementing the GEOS-Chem model side-by-side to CAM-chem within a common Earth system model, we identify and evaluate specific differences between the two models and their impacts on key chemical species.
Joël Thanwerdas, Marielle Saunois, Antoine Berchet, Isabelle Pison, and Philippe Bousquet
Atmos. Chem. Phys., 24, 2129–2167, https://doi.org/10.5194/acp-24-2129-2024, https://doi.org/10.5194/acp-24-2129-2024, 2024
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We investigate the causes of the renewed growth of atmospheric methane (CH4) after 2007 using inverse modeling. We use the additional information provided by observations of CH4 isotopic compositions to better differentiate between the emission categories. Accounting for the large uncertainties in source signatures, our results suggest that the post-2007 increase in atmospheric CH4 was caused by similar increases in emissions from (1) fossil fuels and (2) agriculture and waste.
Ryan S. Williams, Michaela I. Hegglin, Patrick Jöckel, Hella Garny, and Keith P. Shine
Atmos. Chem. Phys., 24, 1389–1413, https://doi.org/10.5194/acp-24-1389-2024, https://doi.org/10.5194/acp-24-1389-2024, 2024
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During winter, a brief but abrupt reversal of the mean stratospheric westerly flow (~30 km high) around the Arctic occurs ~6 times a decade. Using a chemistry–climate model, about half of these events are shown to induce large anomalies in Arctic ozone (>25 %) and water vapour (>±25 %) around ~8–12 km altitude for up to 2–3 months, important for weather forecasting. We also calculate a doubling to trebling of the risk in breaches of mid-latitude surface air quality (ozone) standards (~60 ppbv).
Rona L. Thompson, Stephen A. Montzka, Martin K. Vollmer, Jgor Arduini, Molly Crotwell, Paul B. Krummel, Chris Lunder, Jens Mühle, Simon O'Doherty, Ronald G. Prinn, Stefan Reimann, Isaac Vimont, Hsiang Wang, Ray F. Weiss, and Dickon Young
Atmos. Chem. Phys., 24, 1415–1427, https://doi.org/10.5194/acp-24-1415-2024, https://doi.org/10.5194/acp-24-1415-2024, 2024
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The hydroxyl radical determines the atmospheric lifetimes of numerous species including methane. Since OH is very short-lived, it is not possible to directly measure its concentration on scales relevant for understanding its effect on other species. Here, OH is inferred by looking at changes in hydrofluorocarbons (HFCs). We find that OH levels have been fairly stable over our study period (2004 to 2021), suggesting that OH is not the main driver of the recent increase in atmospheric methane.
Zhendong Wu, Alex Vermeulen, Yousuke Sawa, Ute Karstens, Wouter Peters, Remco de Kok, Xin Lan, Yasuyuki Nagai, Akinori Ogi, and Oksana Tarasova
Atmos. Chem. Phys., 24, 1249–1264, https://doi.org/10.5194/acp-24-1249-2024, https://doi.org/10.5194/acp-24-1249-2024, 2024
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This study focuses on exploring the differences in calculating global surface CO2 and its growth rate, considering the impact of analysis methodologies and site selection. Our study reveals that the current global CO2 network has a good capacity to represent global surface CO2 and its growth rate, as well as trends in atmospheric CO2 mass changes. However, small differences exist in different analyses due to the impact of methodology and site selection.
Beth S. Nelson, Zhenze Liu, Freya A. Squires, Marvin Shaw, James R. Hopkins, Jacqueline F. Hamilton, Andrew R. Rickard, Alastair C. Lewis, Zongbo Shi, and James D. Lee
EGUsphere, https://doi.org/10.5194/egusphere-2023-2910, https://doi.org/10.5194/egusphere-2023-2910, 2024
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The impact of combined air quality and carbon neutrality policies on O3 formation in Beijing were investigated. Emissions inventory data was used to estimate future pollutant mixing ratios, relative to ground-level observations. O3 production was found to be most sensitive to changes in alkenes but large reductions in less reactive compounds led to larger reductions in future O3 production. This study highlights the importance of understanding the emission trajectories of organic pollutants.
Yang Yang, Yang Zhou, Hailong Wang, Mengyun Li, Huimin Li, Pinya Wang, Xu Yue, Ke Li, Jia Zhu, and Hong Liao
Atmos. Chem. Phys., 24, 1177–1191, https://doi.org/10.5194/acp-24-1177-2024, https://doi.org/10.5194/acp-24-1177-2024, 2024
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This study reveals that extreme ozone pollution over the North China Plain and Yangtze River Delta is due to the chemical production related to hot and dry conditions, and the regional transport explains the ozone pollution over the Sichuan Basin and Pearl River Delta. The frequency of meteorological conditions of the extreme ozone pollution increases from the past to the future. The sustainable scenario is the optimal path to retaining clean air in China in the future.
Victoria A. Flood, Kimberly Strong, Cynthia H. Whaley, Kaley A. Walker, Thomas Blumenstock, James W. Hannigan, Johan Mellqvist, Justus Notholt, Mathias Palm, Amelie N. Röhling, Stephen Arnold, Stephen Beagley, Rong-You Chien, Jesper Christensen, Makoto Deushi, Srdjan Dobricic, Xinyi Dong, Joshua S. Fu, Michael Gauss, Wanmin Gong, Joakim Langner, Kathy S. Law, Louis Marelle, Tatsuo Onishi, Naga Oshima, David A. Plummer, Luca Pozzoli, Jean-Christophe Raut, Manu A. Thomas, Svetlana Tsyro, and Steven Turnock
Atmos. Chem. Phys., 24, 1079–1118, https://doi.org/10.5194/acp-24-1079-2024, https://doi.org/10.5194/acp-24-1079-2024, 2024
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It is important to understand the composition of the Arctic atmosphere and how it is changing. Atmospheric models provide simulations that can inform policy. This study examines simulations of CH4, CO, and O3 by 11 models. Model performance is assessed by comparing results matched in space and time to measurements from five high-latitude ground-based infrared spectrometers. This work finds that models generally underpredict the concentrations of these gases in the Arctic troposphere.
Roger Teoh, Zebediah Engberg, Marc Shapiro, Lynnette Dray, and Marc E. J. Stettler
Atmos. Chem. Phys., 24, 725–744, https://doi.org/10.5194/acp-24-725-2024, https://doi.org/10.5194/acp-24-725-2024, 2024
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Emissions from aircraft contribute to climate change and degrade air quality. We describe an up-to-date 4D emissions inventory of global aviation from 2019 to 2021 based on actual flown trajectories. In 2019, 40.2 million flights collectively travelled 61 billion kilometres using 283 Tg of fuel. Long-haul flights were responsible for 43 % of CO2. The emissions inventory is made available for use in future studies to evaluate the negative externalities arising from global aviation.
Jonas Hachmeister, Oliver Schneising, Michael Buchwitz, John P. Burrows, Justus Notholt, and Matthias Buschmann
Atmos. Chem. Phys., 24, 577–595, https://doi.org/10.5194/acp-24-577-2024, https://doi.org/10.5194/acp-24-577-2024, 2024
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We quantified changes in atmospheric methane concentrations using satellite data and a dynamic linear model approach. We calculated global annual methane increases for the years 2019–2022, which are in good agreement with other sources. For zonal methane growth rates, we identified strong inter-hemispheric differences in 2019 and 2022. For 2022, we could attribute decreases in the global growth rate to the Northern Hemisphere, possibly related to a reduction in anthropogenic emissions.
Glenn-Michael Oomen, Jean-François Müller, Trissevgeni Stavrakou, Isabelle De Smedt, Thomas Blumenstock, Rigel Kivi, Maria Makarova, Mathias Palm, Amelie Röhling, Yao Té, Corinne Vigouroux, Martina M. Friedrich, Udo Frieß, François Hendrick, Alexis Merlaud, Ankie Piters, Andreas Richter, Michel Van Roozendael, and Thomas Wagner
Atmos. Chem. Phys., 24, 449–474, https://doi.org/10.5194/acp-24-449-2024, https://doi.org/10.5194/acp-24-449-2024, 2024
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Natural emissions from vegetation have a profound impact on air quality for their role in the formation of harmful tropospheric ozone and organic aerosols, yet these emissions are highly uncertain. In this study, we quantify emissions of organic gases over Europe using high-quality satellite measurements of formaldehyde. These satellite observations suggest that emissions from vegetation are much higher than predicted by models, especially in southern Europe.
Yongliang She, Jingyi Li, Xiaopu Lyu, Hai Guo, Momei Qin, Xiaodong Xie, Kangjia Gong, Fei Ye, Jianjiong Mao, Lin Huang, and Jianlin Hu
Atmos. Chem. Phys., 24, 219–233, https://doi.org/10.5194/acp-24-219-2024, https://doi.org/10.5194/acp-24-219-2024, 2024
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In this study, we use multi-site volatile organic compound (VOC) measurements to evaluate the CMAQ-model-predicted VOCs and assess the impacts of VOC bias on O3 simulation. Our results demonstrate that current modeling setups and emission inventories are likely to underpredict VOC concentrations, and this underprediction of VOCs contributes to lower O3 predictions in China.
Peiyang Cheng, Arastoo Pour-Biazar, Yuling Wu, Shi Kuang, Richard T. McNider, and William J. Koshak
Atmos. Chem. Phys., 24, 41–63, https://doi.org/10.5194/acp-24-41-2024, https://doi.org/10.5194/acp-24-41-2024, 2024
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Lightning-induced nitrogen monoxide (LNO) emission can be estimated from geostationary satellite observations. The present study uses the LNO emission estimates derived from geostationary satellite observations in an air quality modeling system to investigate the impact of LNO on air quality. Results indicate that significant ozone increase could be due to long-distance chemical transport, lightning activity in the upwind direction, and the mixing of high LNO (or ozone) plumes.
Christian Rödenbeck, Karina E. Adcock, Markus Eritt, Maksym Gachkivskyi, Christoph Gerbig, Samuel Hammer, Armin Jordan, Ralph F. Keeling, Ingeborg Levin, Fabian Maier, Andrew C. Manning, Heiko Moossen, Saqr Munassar, Penelope A. Pickers, Michael Rothe, Yasunori Tohjima, and Sönke Zaehle
Atmos. Chem. Phys., 23, 15767–15782, https://doi.org/10.5194/acp-23-15767-2023, https://doi.org/10.5194/acp-23-15767-2023, 2023
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The carbon dioxide content of the Earth atmosphere is increasing due to human emissions from burning of fossil fuels, causing global climate change. The strength of the fossil-fuel emissions is estimated by inventories based on energy data, but independent validation of these inventories has been recommended by the Intergovernmental Panel on Climate Change. Here we investigate the potential to validate inventories based on measurements of small changes in the atmospheric oxygen content.
Xuewei Hou, Oliver Wild, Bin Zhu, and James Lee
Atmos. Chem. Phys., 23, 15395–15411, https://doi.org/10.5194/acp-23-15395-2023, https://doi.org/10.5194/acp-23-15395-2023, 2023
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In response to the climate crisis, many countries have committed to net zero in a certain future year. The impacts of net-zero scenarios on tropospheric O3 are less well studied and remain unclear. In this study, we quantified the changes of tropospheric O3 budgets, spatiotemporal distributions of future surface O3 in east Asia and regional O3 source contributions for 2060 under a net-zero scenario using the NCAR Community Earth System Model (CESM) and online O3-tagging methods.
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Short summary
We assess observed and modeled ozone weekend–weekday differences in the USA from 2002–2019. A subset of urban areas that were NOx-saturated at the beginning of the period transitioned to NOx-limited conditions. Multiple rural areas of California were NOx-limited for the entire period but become less influenced by local day-of-week emission patterns in more recent years. The model produces more NOx-saturated conditions than the observations but captures trends in weekend–weekday ozone patterns.
We assess observed and modeled ozone weekend–weekday differences in the USA from 2002–2019. A...
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