Articles | Volume 19, issue 16
https://doi.org/10.5194/amt-19-5539-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-19-5539-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Aug 2026
Research article |
| 28 Aug 2026
| 28 Aug 2026
Evaluation of Pandora HCHO and NO2 with airborne in situ observations
Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA
Glenn M. Wolfe
Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center Greenbelt, MD, USA
Timothy Canty
Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA
Jason St. Clair
Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center Greenbelt, MD, USA
University of Maryland, Baltimore County, Baltimore, MD, USA
Erin Delaria
Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center Greenbelt, MD, USA
Jennifer Kaiser
School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
Nidhi Desai
School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
Andrew Rollins
NOAA Chemical Science Laboratory, Boulder, CO, USA
Eleanor Waxman
NOAA Chemical Science Laboratory, Boulder, CO, USA
University of Colorado Boulder, CIRES, Boulder, CO, USA
Kristen Zuraski
NOAA Chemical Science Laboratory, Boulder, CO, USA
University of Colorado Boulder, CIRES, Boulder, CO, USA
Bryan Place
Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center Greenbelt, MD, USA
Sciglob Instruments and Services LLC, Columbia, MD, USA
Apoorva Pandey
Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center Greenbelt, MD, USA
University of Maryland, Baltimore County, Baltimore, MD, USA
Akanksha Singh
Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA
Allison Ring
Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA
Charles Gatebe
NASA Ames Research Center, Moffett Field, CA, USA
Jonathan Dean-Day
Bay Area Environmental Research Institute, Moffett Field, CA, USA
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James R. Campbell, Brice Temime-Roussel, Barbara D'Anna, Kathy S. Law, Weihang Zhang, Rodney J. Weber, Michael Battaglia Jr., Kayane K. Dingilian, Meeta Cesler-Maloney, Jason M. St. Clair, and Jingqiu Mao
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Jasna V. Pittman, Bruce C. Daube, Steven C. Wofsy, Elliot L. Atlas, Maria A. Navarro, Eric J. Hintsa, Fred L. Moore, Geoff S. Dutton, James W. Elkins, Troy D. Thornberry, Andrew W. Rollins, Eric J. Jensen, Thaopaul Bui, Jonathan Dean-Day, and Leonhard Pfister
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Amir H. Souri, Gonzalo González Abad, Glenn M. Wolfe, Tijl Verhoelst, Corinne Vigouroux, Gaia Pinardi, Steven Compernolle, Bavo Langerock, Bryan N. Duncan, and Matthew S. Johnson
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We establish a simple yet robust relationship between ozone production rates and geophysical parameters obtained from several intensive atmospheric composition campaigns. We show that satellite remote sensing data can effectively constrain these parameters, enabling us to produce the first global maps of ozone production rates with unprecedented resolution.
Chelsea E. Stockwell, Matthew M. Coggon, Rebecca H. Schwantes, Colin Harkins, Bert Verreyken, Congmeng Lyu, Qindan Zhu, Lu Xu, Jessica B. Gilman, Aaron Lamplugh, Jeff Peischl, Michael A. Robinson, Patrick R. Veres, Meng Li, Andrew W. Rollins, Kristen Zuraski, Sunil Baidar, Shang Liu, Toshihiro Kuwayama, Steven S. Brown, Brian C. McDonald, and Carsten Warneke
Atmos. Chem. Phys., 25, 1121–1143, https://doi.org/10.5194/acp-25-1121-2025, https://doi.org/10.5194/acp-25-1121-2025, 2025
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In urban areas, emissions from everyday products like paints, cleaners, and personal care products, along with non-traditional sources such as cooking, are increasingly important and impact air quality. This study uses a box model to evaluate how these emissions impact ozone in the Los Angeles Basin and quantifies the impact of gaseous cooking emissions. Accurate representation of these and other anthropogenic sources in inventories is crucial for informing effective air quality policies.
Jin Liao, Glenn M. Wolfe, Alexander E. Kotsakis, Julie M. Nicely, Jason M. St. Clair, Thomas F. Hanisco, Gonzalo González Abad, Caroline R. Nowlan, Zolal Ayazpour, Isabelle De Smedt, Eric C. Apel, and Rebecca S. Hornbrook
Atmos. Meas. Tech., 18, 1–16, https://doi.org/10.5194/amt-18-1-2025, https://doi.org/10.5194/amt-18-1-2025, 2025
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Validation of satellite HCHO over the remote marine regions is relatively low, and modeled HCHO in these regions is usually added as a global satellite HCHO background. This paper intercompares three satellite HCHO retrievals and validates them against in situ observations from the NASA ATom mission. All retrievals are correlated with ATom-integrated columns over remote oceans, with OMI SAO (v004) showing the best agreement. A persistent low bias is found in all retrievals at high latitudes.
Bryan N. Duncan, Daniel C. Anderson, Arlene M. Fiore, Joanna Joiner, Nickolay A. Krotkov, Can Li, Dylan B. Millet, Julie M. Nicely, Luke D. Oman, Jason M. St. Clair, Joshua D. Shutter, Amir H. Souri, Sarah A. Strode, Brad Weir, Glenn M. Wolfe, Helen M. Worden, and Qindan Zhu
Atmos. Chem. Phys., 24, 13001–13023, https://doi.org/10.5194/acp-24-13001-2024, https://doi.org/10.5194/acp-24-13001-2024, 2024
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Trace gases emitted to or formed within the atmosphere may be chemically or physically removed from the atmosphere. One trace gas, the hydroxyl radical (OH), is responsible for initiating the chemical removal of many trace gases, including some greenhouse gases. Despite its importance, scientists have not been able to adequately measure OH. In this opinion piece, we discuss promising new methods to indirectly constrain OH using satellite data of trace gases that control the abundance of OH.
T. Nash Skipper, Emma L. D'Ambro, Forwood C. Wiser, V. Faye McNeill, Rebecca H. Schwantes, Barron H. Henderson, Ivan R. Piletic, Colleen B. Baublitz, Jesse O. Bash, Andrew R. Whitehill, Lukas C. Valin, Asher P. Mouat, Jennifer Kaiser, Glenn M. Wolfe, Jason M. St. Clair, Thomas F. Hanisco, Alan Fried, Bryan K. Place, and Havala O.T. Pye
Atmos. Chem. Phys., 24, 12903–12924, https://doi.org/10.5194/acp-24-12903-2024, https://doi.org/10.5194/acp-24-12903-2024, 2024
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We develop the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM) version 2 to improve predictions of formaldehyde in ambient air compared to satellite-, aircraft-, and ground-based observations. With the updated chemistry, we estimate the cancer risk from inhalation exposure to ambient formaldehyde across the contiguous USA and predict that 40 % of this risk is controllable through reductions in anthropogenic emissions of nitrogen oxides and reactive organic carbon.
Andrew O. Langford, Raul J. Alvarez II, Kenneth C. Aikin, Sunil Baidar, W. Alan Brewer, Steven S. Brown, Matthew M. Coggan, Patrick D. Cullis, Jessica Gilman, Georgios I. Gkatzelis, Detlev Helmig, Bryan J. Johnson, K. Emma Knowland, Rajesh Kumar, Aaron D. Lamplugh, Audra McClure-Begley, Brandi J. McCarty, Ann M. Middlebrook, Gabriele Pfister, Jeff Peischl, Irina Petropavlovskikh, Pamela S. Rickley, Andrew W. Rollins, Scott P. Sandberg, Christoph J. Senff, and Carsten Warneke
EGUsphere, https://doi.org/10.5194/egusphere-2024-1938, https://doi.org/10.5194/egusphere-2024-1938, 2024
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High ozone (O3) formed by reactions of nitrogen oxides (NOx) and volatile organic compounds (VOCs) can harm human health and welfare. High O3 is usually associated with hot summer days, but under certain conditions, high O3 can also form under winter conditions. In this study, we describe a high O3 event that occurred in Colorado during the COVID-19 quarantine that was caused in part by the decrease in traffic, and in part by a shallow inversion created by descent of stratospheric air.
Andrea E. Gordon, Cameron R. Homeyer, Jessica B. Smith, Rei Ueyama, Jonathan M. Dean-Day, Elliot L. Atlas, Kate Smith, Jasna V. Pittman, David S. Sayres, David M. Wilmouth, Apoorva Pandey, Jason M. St. Clair, Thomas F. Hanisco, Jennifer Hare, Reem A. Hannun, Steven Wofsy, Bruce C. Daube, and Stephen Donnelly
Atmos. Chem. Phys., 24, 7591–7608, https://doi.org/10.5194/acp-24-7591-2024, https://doi.org/10.5194/acp-24-7591-2024, 2024
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In situ airborne observations of ongoing tropopause-overshooting convection and an above-anvil cirrus plume from the 31 May 2022 flight of the Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) field campaign are examined. Upper troposphere and lower stratosphere composition changes are evaluated along with possible contributing dynamical and physical processes. Measurements reveal multiple changes in air mass composition and stratospheric hydration throughout the flight.
Alessia A. Colussi, Daniel Persaud, Melodie Lao, Bryan K. Place, Rachel F. Hems, Susan E. Ziegler, Kate A. Edwards, Cora J. Young, and Trevor C. VandenBoer
Atmos. Meas. Tech., 17, 3697–3718, https://doi.org/10.5194/amt-17-3697-2024, https://doi.org/10.5194/amt-17-3697-2024, 2024
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A new modular and affordable instrument was developed to automatically collect wet deposition continuously with an off-grid solar top-up power package. Monthly collections were performed across the Newfoundland and Labrador Boreal Ecosystem Latitudinal Transect of experimental forest sites from 2015 to 2016. The proof-of-concept systems were validated with baseline measurements of pH and conductivity and then applied to dissolved organic carbon as an analyte of emerging biogeochemical interest.
Asher P. Mouat, Zelda A. Siegel, and Jennifer Kaiser
Atmos. Meas. Tech., 17, 1979–1994, https://doi.org/10.5194/amt-17-1979-2024, https://doi.org/10.5194/amt-17-1979-2024, 2024
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Three fast-measurement formaldehyde monitors were deployed at two field sites in Atlanta, GA, over 1 year. Four different zeroing methods were tested to develop an optimal field setup as well as procedures for instrument calibration. Observations agreed well after calibration but were much higher compared to the TO-11A monitoring method, which is the golden standard. Historical HCHO concentrations were compared with measurements in this work, showing a 22 % reduction in midday HCHO since 1999.
Huisheng Bian, Mian Chin, Peter R. Colarco, Eric C. Apel, Donald R. Blake, Karl Froyd, Rebecca S. Hornbrook, Jose Jimenez, Pedro Campuzano Jost, Michael Lawler, Mingxu Liu, Marianne Tronstad Lund, Hitoshi Matsui, Benjamin A. Nault, Joyce E. Penner, Andrew W. Rollins, Gregory Schill, Ragnhild B. Skeie, Hailong Wang, Lu Xu, Kai Zhang, and Jialei Zhu
Atmos. Chem. Phys., 24, 1717–1741, https://doi.org/10.5194/acp-24-1717-2024, https://doi.org/10.5194/acp-24-1717-2024, 2024
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This work studies sulfur in the remote troposphere at global and seasonal scales using aircraft measurements and multi-model simulations. The goal is to understand the sulfur cycle over remote oceans, spread of model simulations, and observation–model discrepancies. Such an understanding and comparison with real observations are crucial to narrow down the uncertainties in model sulfur simulations and improve understanding of the sulfur cycle in atmospheric air quality, climate, and ecosystems.
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.
Kevin C. Cossel, Eleanor M. Waxman, Eli Hoenig, Daniel Hesselius, Christopher Chaote, Ian Coddington, and Nathan R. Newbury
Atmos. Meas. Tech., 16, 5697–5707, https://doi.org/10.5194/amt-16-5697-2023, https://doi.org/10.5194/amt-16-5697-2023, 2023
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Measurements of the emission rate of a gas or gases from point and area sources are important in a range of monitoring applications. We demonstrate a method for rapid quantification of the emission rate of multiple gases using a spatially scannable open-path sensor. The open-path spectrometer measures the total column density of gases between the spectrometer and a retroreflector mounted on an uncrewed aerial vehicle (UAV). By scanning the UAV altitude, we can determine the total gas emissions.
Emma L. Yates, Laura T. Iraci, Susan S. Kulawik, Ju-Mee Ryoo, Josette E. Marrero, Caroline L. Parworth, Jason M. St. Clair, Thomas F. Hanisco, Thao Paul V. Bui, Cecilia S. Chang, and Jonathan M. Dean-Day
Earth Syst. Sci. Data, 15, 2375–2389, https://doi.org/10.5194/essd-15-2375-2023, https://doi.org/10.5194/essd-15-2375-2023, 2023
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The Alpha Jet Atmospheric eXperiment (AJAX) flew scientific flights between 2011 and 2018 providing measurements of carbon dioxide, methane, ozone, formaldehyde, water vapor and meteorological parameters over California and Nevada, USA. AJAX was a multi-year, multi-objective, multi-instrument program with a variety of sampling strategies resulting in an extensive dataset of interest to a wide variety of users. AJAX measurements have been published at https://asdc.larc.nasa.gov/project/AJAX.
Amir H. Souri, Matthew S. Johnson, Glenn M. Wolfe, James H. Crawford, Alan Fried, Armin Wisthaler, William H. Brune, Donald R. Blake, Andrew J. Weinheimer, Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Corinne Vigouroux, Bavo Langerock, Sungyeon Choi, Lok Lamsal, Lei Zhu, Shuai Sun, Ronald C. Cohen, Kyung-Eun Min, Changmin Cho, Sajeev Philip, Xiong Liu, and Kelly Chance
Atmos. Chem. Phys., 23, 1963–1986, https://doi.org/10.5194/acp-23-1963-2023, https://doi.org/10.5194/acp-23-1963-2023, 2023
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We have rigorously characterized different sources of error in satellite-based HCHO / NO2 tropospheric columns, a widely used metric for diagnosing near-surface ozone sensitivity. Specifically, the errors were categorized/quantified into (i) an inherent chemistry error, (ii) the decoupled relationship between columns and the near-surface concentration, (iii) the spatial representativeness error of ground satellite pixels, and (iv) the satellite retrieval errors.
Hao Guo, Clare M. Flynn, Michael J. Prather, Sarah A. Strode, Stephen D. Steenrod, Louisa Emmons, Forrest Lacey, Jean-Francois Lamarque, Arlene M. Fiore, Gus Correa, Lee T. Murray, Glenn M. Wolfe, Jason M. St. Clair, Michelle Kim, John Crounse, Glenn Diskin, Joshua DiGangi, Bruce C. Daube, Roisin Commane, Kathryn McKain, Jeff Peischl, Thomas B. Ryerson, Chelsea Thompson, Thomas F. Hanisco, Donald Blake, Nicola J. Blake, Eric C. Apel, Rebecca S. Hornbrook, James W. Elkins, Eric J. Hintsa, Fred L. Moore, and Steven C. Wofsy
Atmos. Chem. Phys., 23, 99–117, https://doi.org/10.5194/acp-23-99-2023, https://doi.org/10.5194/acp-23-99-2023, 2023
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We have prepared a unique and unusual result from the recent ATom aircraft mission: a measurement-based derivation of the production and loss rates of ozone and methane over the ocean basins. These are the key products of chemistry models used in assessments but have thus far lacked observational metrics. It also shows the scales of variability of atmospheric chemical rates and provides a major challenge to the atmospheric models.
Pamela S. Rickly, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Glenn M. Wolfe, Ryan Bennett, Ilann Bourgeois, John D. Crounse, Jack E. Dibb, Joshua P. DiGangi, Glenn S. Diskin, Maximilian Dollner, Emily M. Gargulinski, Samuel R. Hall, Hannah S. Halliday, Thomas F. Hanisco, Reem A. Hannun, Jin Liao, Richard Moore, Benjamin A. Nault, John B. Nowak, Jeff Peischl, Claire E. Robinson, Thomas Ryerson, Kevin J. Sanchez, Manuel Schöberl, Amber J. Soja, Jason M. St. Clair, Kenneth L. Thornhill, Kirk Ullmann, Paul O. Wennberg, Bernadett Weinzierl, Elizabeth B. Wiggins, Edward L. Winstead, and Andrew W. Rollins
Atmos. Chem. Phys., 22, 15603–15620, https://doi.org/10.5194/acp-22-15603-2022, https://doi.org/10.5194/acp-22-15603-2022, 2022
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Biomass burning sulfur dioxide (SO2) emission factors range from 0.27–1.1 g kg-1 C. Biomass burning SO2 can quickly form sulfate and organosulfur, but these pathways are dependent on liquid water content and pH. Hydroxymethanesulfonate (HMS) appears to be directly emitted from some fire sources but is not the sole contributor to the organosulfur signal. It is shown that HMS and organosulfur chemistry may be an important S(IV) reservoir with the fate dependent on the surrounding conditions.
Youhua Tang, Patrick C. Campbell, Pius Lee, Rick Saylor, Fanglin Yang, Barry Baker, Daniel Tong, Ariel Stein, Jianping Huang, Ho-Chun Huang, Li Pan, Jeff McQueen, Ivanka Stajner, Jose Tirado-Delgado, Youngsun Jung, Melissa Yang, Ilann Bourgeois, Jeff Peischl, Tom Ryerson, Donald Blake, Joshua Schwarz, Jose-Luis Jimenez, James Crawford, Glenn Diskin, Richard Moore, Johnathan Hair, Greg Huey, Andrew Rollins, Jack Dibb, and Xiaoyang Zhang
Geosci. Model Dev., 15, 7977–7999, https://doi.org/10.5194/gmd-15-7977-2022, https://doi.org/10.5194/gmd-15-7977-2022, 2022
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This paper compares two meteorological datasets for driving a regional air quality model: a regional meteorological model using WRF (WRF-CMAQ) and direct interpolation from an operational global model (GFS-CMAQ). In the comparison with surface measurements and aircraft data in summer 2019, these two methods show mixed performance depending on the corresponding meteorological settings. Direct interpolation is found to be a viable method to drive air quality models.
Alice Crawford, Tianfeng Chai, Binyu Wang, Allison Ring, Barbara Stunder, Christopher P. Loughner, Michael Pavolonis, and Justin Sieglaff
Atmos. Chem. Phys., 22, 13967–13996, https://doi.org/10.5194/acp-22-13967-2022, https://doi.org/10.5194/acp-22-13967-2022, 2022
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This study describes the development of a workflow which produces probabilistic and quantitative forecasts of volcanic ash in the atmosphere. The workflow includes methods of incorporating satellite observations of the ash cloud into a modeling framework as well as verification statistics that can be used to guide further model development and provide information for risk-based approaches to flight planning.
Nicole A. June, Anna L. Hodshire, Elizabeth B. Wiggins, Edward L. Winstead, Claire E. Robinson, K. Lee Thornhill, Kevin J. Sanchez, Richard H. Moore, Demetrios Pagonis, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Matthew M. Coggon, Jonathan M. Dean-Day, T. Paul Bui, Jeff Peischl, Robert J. Yokelson, Matthew J. Alvarado, Sonia M. Kreidenweis, Shantanu H. Jathar, and Jeffrey R. Pierce
Atmos. Chem. Phys., 22, 12803–12825, https://doi.org/10.5194/acp-22-12803-2022, https://doi.org/10.5194/acp-22-12803-2022, 2022
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The evolution of organic aerosol composition and size is uncertain due to variability within and between smoke plumes. We examine the impact of plume concentration on smoke evolution from smoke plumes sampled by the NASA DC-8 during FIREX-AQ. We find that observed organic aerosol and size distribution changes are correlated to plume aerosol mass concentrations. Additionally, coagulation explains the majority of the observed growth.
Asher P. Mouat, Clare Paton-Walsh, Jack B. Simmons, Jhonathan Ramirez-Gamboa, David W. T. Griffith, and Jennifer Kaiser
Atmos. Chem. Phys., 22, 11033–11047, https://doi.org/10.5194/acp-22-11033-2022, https://doi.org/10.5194/acp-22-11033-2022, 2022
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We examine emissions of volatile organic compounds from 2020 wildfires in forested regions of Australia (AU). We find that biomass burning in temperate regions of the US and AU emit similar species in similar proportion, both in natural and lab settings. This suggests studies of wildfires in one region may be used to help improve air quality models in other parts of the world. We observe time series of ozone and nitrogen dioxide. Last, we look at which compounds contribute most to OH reactivity.
Ilann Bourgeois, Jeff Peischl, J. Andrew Neuman, Steven S. Brown, Hannah M. Allen, Pedro Campuzano-Jost, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Jessica B. Gilman, Georgios I. Gkatzelis, Hongyu Guo, Hannah A. Halliday, Thomas F. Hanisco, Christopher D. Holmes, L. Gregory Huey, Jose L. Jimenez, Aaron D. Lamplugh, Young Ro Lee, Jakob Lindaas, Richard H. Moore, Benjamin A. Nault, John B. Nowak, Demetrios Pagonis, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Vanessa Selimovic, Jason M. St. Clair, David Tanner, Krystal T. Vasquez, Patrick R. Veres, Carsten Warneke, Paul O. Wennberg, Rebecca A. Washenfelder, Elizabeth B. Wiggins, Caroline C. Womack, Lu Xu, Kyle J. Zarzana, and Thomas B. Ryerson
Atmos. Meas. Tech., 15, 4901–4930, https://doi.org/10.5194/amt-15-4901-2022, https://doi.org/10.5194/amt-15-4901-2022, 2022
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Understanding fire emission impacts on the atmosphere is key to effective air quality management and requires accurate measurements. We present a comparison of airborne measurements of key atmospheric species in ambient air and in fire smoke. We show that most instruments performed within instrument uncertainties. In some cases, further work is needed to fully characterize instrument performance. Comparing independent measurements using different techniques is important to assess their accuracy.
Tianlang Zhao, Jingqiu Mao, William R. Simpson, Isabelle De Smedt, Lei Zhu, Thomas F. Hanisco, Glenn M. Wolfe, Jason M. St. Clair, Gonzalo González Abad, Caroline R. Nowlan, Barbara Barletta, Simone Meinardi, Donald R. Blake, Eric C. Apel, and Rebecca S. Hornbrook
Atmos. Chem. Phys., 22, 7163–7178, https://doi.org/10.5194/acp-22-7163-2022, https://doi.org/10.5194/acp-22-7163-2022, 2022
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Monitoring formaldehyde (HCHO) can help us understand Arctic vegetation change. Here, we compare satellite data and model and show that Alaska summertime HCHO is largely dominated by a background from methane oxidation during mild wildfire years and is dominated by wildfire (largely from direct emission of fire) during strong fire years. Consequently, it is challenging to use satellite HCHO to study vegetation change in the Arctic region.
Glenn M. Wolfe, Thomas F. Hanisco, Heather L. Arkinson, Donald R. Blake, Armin Wisthaler, Tomas Mikoviny, Thomas B. Ryerson, Ilana Pollack, Jeff Peischl, Paul O. Wennberg, John D. Crounse, Jason M. St. Clair, Alex Teng, L. Gregory Huey, Xiaoxi Liu, Alan Fried, Petter Weibring, Dirk Richter, James Walega, Samuel R. Hall, Kirk Ullmann, Jose L. Jimenez, Pedro Campuzano-Jost, T. Paul Bui, Glenn Diskin, James R. Podolske, Glen Sachse, and Ronald C. Cohen
Atmos. Chem. Phys., 22, 4253–4275, https://doi.org/10.5194/acp-22-4253-2022, https://doi.org/10.5194/acp-22-4253-2022, 2022
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Smoke plumes are chemically complex. This work combines airborne observations of smoke plume composition with a photochemical model to probe the production of ozone and the fate of reactive gases in the outflow of a large wildfire. Model–measurement comparisons illustrate how uncertain emissions and chemical processes propagate into simulated chemical evolution. Results provide insight into how this system responds to perturbations, which can help guide future observation and modeling efforts.
Martin Breitenlechner, Gordon A. Novak, J. Andrew Neuman, Andrew W. Rollins, and Patrick R. Veres
Atmos. Meas. Tech., 15, 1159–1169, https://doi.org/10.5194/amt-15-1159-2022, https://doi.org/10.5194/amt-15-1159-2022, 2022
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We coupled a new ion source to a commercially available state-of-the-art trace gas analyzer. The instrument is particularly well suited for conducting high-altitude observations, addressing the challenges of low ambient pressures and a complex sample matrix. The new instrument and ion source provides significant advantages to more traditional modes of operation, without sacrificing the sensitivity and flexibility of this technique.
Debora Griffin, Chris A. McLinden, Enrico Dammers, Cristen Adams, Chelsea E. Stockwell, Carsten Warneke, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Kyle J. Zarzana, Jake P. Rowe, Rainer Volkamer, Christoph Knote, Natalie Kille, Theodore K. Koenig, Christopher F. Lee, Drew Rollins, Pamela S. Rickly, Jack Chen, Lukas Fehr, Adam Bourassa, Doug Degenstein, Katherine Hayden, Cristian Mihele, Sumi N. Wren, John Liggio, Ayodeji Akingunola, and Paul Makar
Atmos. Meas. Tech., 14, 7929–7957, https://doi.org/10.5194/amt-14-7929-2021, https://doi.org/10.5194/amt-14-7929-2021, 2021
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Satellite-derived NOx emissions from biomass burning are estimated with TROPOMI observations. Two common emission estimation methods are applied, and sensitivity tests with model output were performed to determine the accuracy of these methods. The effect of smoke aerosols on TROPOMI NO2 columns is estimated and compared to aircraft observations from four different aircraft campaigns measuring biomass burning plumes in 2018 and 2019 in North America.
Jin Liao, Glenn M. Wolfe, Reem A. Hannun, Jason M. St. Clair, Thomas F. Hanisco, Jessica B. Gilman, Aaron Lamplugh, Vanessa Selimovic, Glenn S. Diskin, John B. Nowak, Hannah S. Halliday, Joshua P. DiGangi, Samuel R. Hall, Kirk Ullmann, Christopher D. Holmes, Charles H. Fite, Anxhelo Agastra, Thomas B. Ryerson, Jeff Peischl, Ilann Bourgeois, Carsten Warneke, Matthew M. Coggon, Georgios I. Gkatzelis, Kanako Sekimoto, Alan Fried, Dirk Richter, Petter Weibring, Eric C. Apel, Rebecca S. Hornbrook, Steven S. Brown, Caroline C. Womack, Michael A. Robinson, Rebecca A. Washenfelder, Patrick R. Veres, and J. Andrew Neuman
Atmos. Chem. Phys., 21, 18319–18331, https://doi.org/10.5194/acp-21-18319-2021, https://doi.org/10.5194/acp-21-18319-2021, 2021
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Formaldehyde (HCHO) is an important oxidant precursor and affects the formation of O3 and other secondary pollutants in wildfire plumes. We disentangle the processes controlling HCHO evolution from wildfire plumes sampled by NASA DC-8 during FIREX-AQ. We find that OH abundance rather than normalized OH reactivity is the main driver of fire-to-fire variability in HCHO secondary production and estimate an effective HCHO yield per volatile organic compound molecule oxidized in wildfire plumes.
Zachary C. J. Decker, Michael A. Robinson, Kelley C. Barsanti, Ilann Bourgeois, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Frank M. Flocke, Alessandro Franchin, Carley D. Fredrickson, Georgios I. Gkatzelis, Samuel R. Hall, Hannah Halliday, Christopher D. Holmes, L. Gregory Huey, Young Ro Lee, Jakob Lindaas, Ann M. Middlebrook, Denise D. Montzka, Richard Moore, J. Andrew Neuman, John B. Nowak, Brett B. Palm, Jeff Peischl, Felix Piel, Pamela S. Rickly, Andrew W. Rollins, Thomas B. Ryerson, Rebecca H. Schwantes, Kanako Sekimoto, Lee Thornhill, Joel A. Thornton, Geoffrey S. Tyndall, Kirk Ullmann, Paul Van Rooy, Patrick R. Veres, Carsten Warneke, Rebecca A. Washenfelder, Andrew J. Weinheimer, Elizabeth Wiggins, Edward Winstead, Armin Wisthaler, Caroline Womack, and Steven S. Brown
Atmos. Chem. Phys., 21, 16293–16317, https://doi.org/10.5194/acp-21-16293-2021, https://doi.org/10.5194/acp-21-16293-2021, 2021
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To understand air quality impacts from wildfires, we need an accurate picture of how wildfire smoke changes chemically both day and night as sunlight changes the chemistry of smoke. We present a chemical analysis of wildfire smoke as it changes from midday through the night. We use aircraft observations from the FIREX-AQ field campaign with a chemical box model. We find that even under sunlight typical
nighttimechemistry thrives and controls the fate of key smoke plume chemical processes.
Eric J. Hintsa, Fred L. Moore, Dale F. Hurst, Geoff S. Dutton, Bradley D. Hall, J. David Nance, Ben R. Miller, Stephen A. Montzka, Laura P. Wolton, Audra McClure-Begley, James W. Elkins, Emrys G. Hall, Allen F. Jordan, Andrew W. Rollins, Troy D. Thornberry, Laurel A. Watts, Chelsea R. Thompson, Jeff Peischl, Ilann Bourgeois, Thomas B. Ryerson, Bruce C. Daube, Yenny Gonzalez Ramos, Roisin Commane, Gregory W. Santoni, Jasna V. Pittman, Steven C. Wofsy, Eric Kort, Glenn S. Diskin, and T. Paul Bui
Atmos. Meas. Tech., 14, 6795–6819, https://doi.org/10.5194/amt-14-6795-2021, https://doi.org/10.5194/amt-14-6795-2021, 2021
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We built UCATS to study atmospheric chemistry and transport. It has measured trace gases including CFCs, N2O, SF6, CH4, CO, and H2 with gas chromatography, as well as ozone and water vapor. UCATS has been part of missions to study the tropical tropopause; transport of air into the stratosphere; greenhouse gases, transport, and chemistry in the troposphere; and ozone chemistry, on both piloted and unmanned aircraft. Its design, capabilities, and some results are shown and described here.
Charles A. Brock, Karl D. Froyd, Maximilian Dollner, Christina J. Williamson, Gregory Schill, Daniel M. Murphy, Nicholas J. Wagner, Agnieszka Kupc, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Douglas A. Day, Derek J. Price, Bernadett Weinzierl, Joshua P. Schwarz, Joseph M. Katich, Siyuan Wang, Linghan Zeng, Rodney Weber, Jack Dibb, Eric Scheuer, Glenn S. Diskin, Joshua P. DiGangi, ThaoPaul Bui, Jonathan M. Dean-Day, Chelsea R. Thompson, Jeff Peischl, Thomas B. Ryerson, Ilann Bourgeois, Bruce C. Daube, Róisín Commane, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 15023–15063, https://doi.org/10.5194/acp-21-15023-2021, https://doi.org/10.5194/acp-21-15023-2021, 2021
Short summary
Short summary
The Atmospheric Tomography Mission was an airborne study that mapped the chemical composition of the remote atmosphere. From this, we developed a comprehensive description of aerosol properties that provides a unique, global-scale dataset against which models can be compared. The data show the polluted nature of the remote atmosphere in the Northern Hemisphere and quantify the contributions of sea salt, dust, soot, biomass burning particles, and pollution particles to the haziness of the sky.
Hao Guo, Clare M. Flynn, Michael J. Prather, Sarah A. Strode, Stephen D. Steenrod, Louisa Emmons, Forrest Lacey, Jean-Francois Lamarque, Arlene M. Fiore, Gus Correa, Lee T. Murray, Glenn M. Wolfe, Jason M. St. Clair, Michelle Kim, John Crounse, Glenn Diskin, Joshua DiGangi, Bruce C. Daube, Roisin Commane, Kathryn McKain, Jeff Peischl, Thomas B. Ryerson, Chelsea Thompson, Thomas F. Hanisco, Donald Blake, Nicola J. Blake, Eric C. Apel, Rebecca S. Hornbrook, James W. Elkins, Eric J. Hintsa, Fred L. Moore, and Steven Wofsy
Atmos. Chem. Phys., 21, 13729–13746, https://doi.org/10.5194/acp-21-13729-2021, https://doi.org/10.5194/acp-21-13729-2021, 2021
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The NASA Atmospheric Tomography (ATom) mission built a climatology of the chemical composition of tropospheric air parcels throughout the middle of the Pacific and Atlantic oceans. The level of detail allows us to reconstruct the photochemical budgets of O3 and CH4 over these vast, remote regions. We find that most of the chemical heterogeneity is captured at the resolution used in current global chemistry models and that the majority of reactivity occurs in the
hottest20 % of parcels.
Cited articles
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Short summary
Ground-based spectrometers measuring HCHO and NO2 were compared to airborne in situ observations in the Summer 2023. Total column HCHO is within uncertainty, but with high biases near the surface. NO2 results are highly sensitive to the viewing angle of the ground monitor which must be considered during validation studies. Spectrometers in NYC show good agreement with a geostationary satellite on clear-sky days. Further quantified uncertainty for the monitors is necessary.
Ground-based spectrometers measuring HCHO and NO2 were compared to airborne in situ observations...
