Articles | Volume 13, issue 2
https://doi.org/10.5194/acp-13-1011-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-13-1011-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
24 Jan 2013
Research article |
| 24 Jan 2013
Effect of aerosols and NO2 concentration on ultraviolet actinic flux near Mexico City during MILAGRO: measurements and model calculations
G. G. Palancar
Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, CO, USA
INFIQC-CONICET, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Centro Láser de Ciencias Moleculares, 5000, Córdoba, Argentina
B. L. Lefer
Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX, USA
S. R. Hall
Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, CO, USA
W. J. Shaw
Pacific Northwest National Laboratory, Department of Energy, Richland, WA, USA
C. A. Corr
Earth Systems Research Center, University of New Hampshire, Durham, NH, USA
S. C. Herndon
Aerodyne Research Inc., Billerica, MA, USA
J. R. Slusser
UV-B Monitoring and Research Program, USDA, Colorado State University, Ft. Collins, CO, USA
S. Madronich
Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, CO, USA
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Yutong Liang, Rebecca A. Wernis, Kasper Kristensen, Nathan M. Kreisberg, Philip L. Croteau, Scott C. Herndon, Arthur W. H. Chan, Nga L. Ng, and Allen H. Goldstein
Atmos. Chem. Phys., 23, 12441–12454, https://doi.org/10.5194/acp-23-12441-2023, https://doi.org/10.5194/acp-23-12441-2023, 2023
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We measured the gas–particle partitioning behaviors of biomass burning markers and examined the effect of wildfire organic aerosol on the partitioning of semivolatile organic compounds. Most compounds measured are less volatile than model predictions. Wildfire aerosol enhanced the condensation of polar compounds and caused some nonpolar (e.g., polycyclic aromatic hydrocarbons) compounds to partition into the gas phase, thus affecting their lifetimes in the atmosphere and the mode of exposure.
Jian Guan, Susan Solomon, Sasha Madronich, and Douglas Kinnison
Atmos. Chem. Phys., 23, 10413–10422, https://doi.org/10.5194/acp-23-10413-2023, https://doi.org/10.5194/acp-23-10413-2023, 2023
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This paper provides a novel method to obtain a global and accurate photodissociation coefficient for NO2 (J(NO2)) based on satellite data, and the results are shown to be consistent with model results. The J(NO2) value decreases as the solar zenith angle increases and has a weak altitude dependence. A key finding is that the satellite-derived J(NO2) increases in the polar regions, in good agreement with model predictions, due to the effects of ice and snow on surface albedo.
Sue Ellen Haupt, Branko Kosović, Larry K. Berg, Colleen M. Kaul, Matthew Churchfield, Jeffrey Mirocha, Dries Allaerts, Thomas Brummet, Shannon Davis, Amy DeCastro, Susan Dettling, Caroline Draxl, David John Gagne, Patrick Hawbecker, Pankaj Jha, Timothy Juliano, William Lassman, Eliot Quon, Raj K. Rai, Michael Robinson, William Shaw, and Regis Thedin
Wind Energ. Sci., 8, 1251–1275, https://doi.org/10.5194/wes-8-1251-2023, https://doi.org/10.5194/wes-8-1251-2023, 2023
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The Mesoscale to Microscale Coupling team, part of the U.S. Department of Energy Atmosphere to Electrons (A2e) initiative, has studied various important challenges related to coupling mesoscale models to microscale models. Lessons learned and discerned best practices are described in the context of the cases studied for the purpose of enabling further deployment of wind energy. It also points to code, assessment tools, and data for testing the methods.
Tara I. Yacovitch, Christoph Dyroff, Joseph R. Roscioli, Conner Daube, J. Barry McManus, and Scott C. Herndon
Atmos. Meas. Tech., 16, 1915–1921, https://doi.org/10.5194/amt-16-1915-2023, https://doi.org/10.5194/amt-16-1915-2023, 2023
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Ethylene oxide is a toxic, carcinogenic compound used in the medical and bulk sterilization industry. Here we describe a precise and fast laser-based ethylene oxide monitor. We report months-long concentrations at a Massachusetts site, and we show how they suggest a potential emission source 35 km away. This source, and another, is confirmed by driving the instrument downwind of the sites, where concentrations were tens to tens of thousands of times greater than background levels.
John W. Halfacre, Jordan Stewart, Scott C. Herndon, Joseph R. Roscioli, Christoph Dyroff, Tara I. Yacovitch, Michael Flynn, Stephen J. Andrews, Steven S. Brown, Patrick R. Veres, and Pete M. Edwards
Atmos. Meas. Tech., 16, 1407–1429, https://doi.org/10.5194/amt-16-1407-2023, https://doi.org/10.5194/amt-16-1407-2023, 2023
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This study details a new sampling method for the optical detection of hydrogen chloride (HCl). HCl is an important atmospheric reservoir for chlorine atoms, which can affect nitrogen oxide cycling and the lifetimes of volatile organic compounds and ozone. However, HCl has a high affinity for interacting with surfaces, thereby preventing fast, quantitative measurements. The sampling technique in this study minimizes these surface interactions and provides a high-quality measurement of HCl.
Paul Veers, Katherine Dykes, Sukanta Basu, Alessandro Bianchini, Andrew Clifton, Peter Green, Hannele Holttinen, Lena Kitzing, Branko Kosovic, Julie K. Lundquist, Johan Meyers, Mark O'Malley, William J. Shaw, and Bethany Straw
Wind Energ. Sci., 7, 2491–2496, https://doi.org/10.5194/wes-7-2491-2022, https://doi.org/10.5194/wes-7-2491-2022, 2022
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Wind energy will play a central role in the transition of our energy system to a carbon-free future. However, many underlying scientific issues remain to be resolved before wind can be deployed in the locations and applications needed for such large-scale ambitions. The Grand Challenges are the gaps in the science left behind during the rapid growth of wind energy. This article explains the breadth of the unfinished business and introduces 10 articles that detail the research needs.
William J. Shaw, Larry K. Berg, Mithu Debnath, Georgios Deskos, Caroline Draxl, Virendra P. Ghate, Charlotte B. Hasager, Rao Kotamarthi, Jeffrey D. Mirocha, Paytsar Muradyan, William J. Pringle, David D. Turner, and James M. Wilczak
Wind Energ. Sci., 7, 2307–2334, https://doi.org/10.5194/wes-7-2307-2022, https://doi.org/10.5194/wes-7-2307-2022, 2022
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This paper provides a review of prominent scientific challenges to characterizing the offshore wind resource using as examples phenomena that occur in the rapidly developing wind energy areas off the United States. The paper also describes the current state of modeling and observations in the marine atmospheric boundary layer and provides specific recommendations for filling key current knowledge gaps.
Lindsay M. Sheridan, Raghu Krishnamurthy, Gabriel García Medina, Brian J. Gaudet, William I. Gustafson Jr., Alicia M. Mahon, William J. Shaw, Rob K. Newsom, Mikhail Pekour, and Zhaoqing Yang
Wind Energ. Sci., 7, 2059–2084, https://doi.org/10.5194/wes-7-2059-2022, https://doi.org/10.5194/wes-7-2059-2022, 2022
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Using observations from lidar buoys, five reanalysis and analysis models that support the wind energy community are validated offshore and at rotor-level heights along the California Pacific coast. The models are found to underestimate the observed wind resource. Occasions of large model error occur in conjunction with stable atmospheric conditions, wind speeds associated with peak turbine power production, and mischaracterization of the diurnal wind speed cycle in summer months.
Mauro Morichetti, Sasha Madronich, Giorgio Passerini, Umberto Rizza, Enrico Mancinelli, Simone Virgili, and Mary Barth
Geosci. Model Dev., 15, 6311–6339, https://doi.org/10.5194/gmd-15-6311-2022, https://doi.org/10.5194/gmd-15-6311-2022, 2022
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In the present study, we explore the effect of making simple changes to the existing WRF-Chem MEGAN v2.04 emissions to provide MEGAN updates that can be used independently of the land surface model chosen. The changes made to the MEGAN algorithm implemented in WRF-Chem were the following: (i) update of the emission activity factors, (ii) update of emission factor values for each plant functional type (PFT), and (iii) the assignment of the emission factor by PFT to isoprene.
Yutong Liang, Christos Stamatis, Edward C. Fortner, Rebecca A. Wernis, Paul Van Rooy, Francesca Majluf, Tara I. Yacovitch, Conner Daube, Scott C. Herndon, Nathan M. Kreisberg, Kelley C. Barsanti, and Allen H. Goldstein
Atmos. Chem. Phys., 22, 9877–9893, https://doi.org/10.5194/acp-22-9877-2022, https://doi.org/10.5194/acp-22-9877-2022, 2022
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This article reports the measurements of organic compounds emitted from western US wildfires. We identified and quantified 240 particle-phase compounds and 72 gas-phase compounds emitted in wildfire and related the emissions to the modified combustion efficiency. Higher emissions of diterpenoids and monoterpenes were observed, likely due to distillation from unburned heated vegetation. Our results can benefit future source apportionment and modeling studies as well as exposure assessments.
Andrew J. Lindsay, Daniel C. Anderson, Rebecca A. Wernis, Yutong Liang, Allen H. Goldstein, Scott C. Herndon, Joseph R. Roscioli, Christoph Dyroff, Ed C. Fortner, Philip L. Croteau, Francesca Majluf, Jordan E. Krechmer, Tara I. Yacovitch, Walter B. Knighton, and Ezra C. Wood
Atmos. Chem. Phys., 22, 4909–4928, https://doi.org/10.5194/acp-22-4909-2022, https://doi.org/10.5194/acp-22-4909-2022, 2022
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Wildfire smoke dramatically impacts air quality and often has elevated concentrations of ozone. We present measurements of ozone and its precursors at a rural site periodically impacted by wildfire smoke. Measurements of total peroxy radicals, key ozone precursors that have been studied little within wildfires, compare well with chemical box model predictions. Our results indicate no serious issues with using current chemistry mechanisms to model chemistry in aged wildfire plumes.
Benjamin Sumlin, Edward Fortner, Andrew Lambe, Nishit J. Shetty, Conner Daube, Pai Liu, Francesca Majluf, Scott Herndon, and Rajan K. Chakrabarty
Atmos. Chem. Phys., 21, 11843–11856, https://doi.org/10.5194/acp-21-11843-2021, https://doi.org/10.5194/acp-21-11843-2021, 2021
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We present a comparison of the changes to light absorption behavior and chemical composition of wildfire smoke particles from day- and nighttime oxidation processes and discuss the results within the context of previous laboratory findings.
Dianne Sanchez, Roger Seco, Dasa Gu, Alex Guenther, John Mak, Youngjae Lee, Danbi Kim, Joonyoung Ahn, Don Blake, Scott Herndon, Daun Jeong, John T. Sullivan, Thomas Mcgee, Rokjin Park, and Saewung Kim
Atmos. Chem. Phys., 21, 6331–6345, https://doi.org/10.5194/acp-21-6331-2021, https://doi.org/10.5194/acp-21-6331-2021, 2021
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We present observations of total reactive gases in a suburban forest observatory in the Seoul metropolitan area. The quantitative comparison with speciated trace gas observations illustrated significant underestimation in atmospheric reactivity from the speciated trace gas observational dataset. We present scientific discussion about potential causes.
Camille Mouchel-Vallon, Julia Lee-Taylor, Alma Hodzic, Paulo Artaxo, Bernard Aumont, Marie Camredon, David Gurarie, Jose-Luis Jimenez, Donald H. Lenschow, Scot T. Martin, Janaina Nascimento, John J. Orlando, Brett B. Palm, John E. Shilling, Manish Shrivastava, and Sasha Madronich
Atmos. Chem. Phys., 20, 5995–6014, https://doi.org/10.5194/acp-20-5995-2020, https://doi.org/10.5194/acp-20-5995-2020, 2020
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The GoAmazon 2014/5 field campaign took place near the city of Manaus, Brazil, isolated in the Amazon rainforest, to study the impacts of urban pollution on natural air masses. We simulated this campaign with an extremely detailed organic chemistry model to understand how the city would affect the growth and composition of natural aerosol particles. Discrepancies between the model and the measurements indicate that the chemistry of naturally emitted organic compounds is still poorly understood.
Daun Jeong, Roger Seco, Dasa Gu, Youngro Lee, Benjamin A. Nault, Christoph J. Knote, Tom Mcgee, John T. Sullivan, Jose L. Jimenez, Pedro Campuzano-Jost, Donald R. Blake, Dianne Sanchez, Alex B. Guenther, David Tanner, L. Gregory Huey, Russell Long, Bruce E. Anderson, Samuel R. Hall, Kirk Ullmann, Hye-jung Shin, Scott C. Herndon, Youngjae Lee, Danbi Kim, Joonyoung Ahn, and Saewung Kim
Atmos. Chem. Phys., 19, 12779–12795, https://doi.org/10.5194/acp-19-12779-2019, https://doi.org/10.5194/acp-19-12779-2019, 2019
Conner Daube, Stephen Conley, Ian C. Faloona, Claudia Arndt, Tara I. Yacovitch, Joseph R. Roscioli, and Scott C. Herndon
Atmos. Meas. Tech., 12, 2085–2095, https://doi.org/10.5194/amt-12-2085-2019, https://doi.org/10.5194/amt-12-2085-2019, 2019
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This study describes aircraft measurements of methane from dairy farms in central California. A small deliberate release of a tracer gas is done on the ground and measured from the air and the ratio of methane to tracer used to quantify emissions. Farm-scale methane emissions are determined as well as the fraction of those emissions coming from animal activity versus liquid manure management. These findings were within the uncertainty of two established methods.
Daniel C. Anderson, Jessica Pavelec, Conner Daube, Scott C. Herndon, Walter B. Knighton, Brian M. Lerner, J. Robert Roscioli, Tara I. Yacovitch, and Ezra C. Wood
Atmos. Chem. Phys., 19, 2845–2860, https://doi.org/10.5194/acp-19-2845-2019, https://doi.org/10.5194/acp-19-2845-2019, 2019
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San Antonio is one of the largest cities in the United States and is in non-attainment of the 8 h ozone standard. Using the Aerodyne Mobile Laboratory, we made observations of ozone and its precursors at three sites in the San Antonio region to determine the main drivers of its production. We found that compounds produced by plants were the dominant organic compound for ozone production and that to limit ozone production at the study site, emissions of nitrogen oxides should be reduced.
Victor Lannuque, Marie Camredon, Florian Couvidat, Alma Hodzic, Richard Valorso, Sasha Madronich, Bertrand Bessagnet, and Bernard Aumont
Atmos. Chem. Phys., 18, 13411–13428, https://doi.org/10.5194/acp-18-13411-2018, https://doi.org/10.5194/acp-18-13411-2018, 2018
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Large uncertainties remain in understanding the influence of atmospheric environmental conditions on secondary organic aerosol (SOA) formation, evolution and properties. In this article, the GECKO-A modelling tool has been used in a box model under various environmental conditions to (i) explore the sensitivity of SOA formation and properties to changes on physical and chemical conditions and (ii) develop a volatility-basis-set-type parameterization for air quality models.
Jeffrey D. Mirocha, Matthew J. Churchfield, Domingo Muñoz-Esparza, Raj K. Rai, Yan Feng, Branko Kosović, Sue Ellen Haupt, Barbara Brown, Brandon L. Ennis, Caroline Draxl, Javier Sanz Rodrigo, William J. Shaw, Larry K. Berg, Patrick J. Moriarty, Rodman R. Linn, Veerabhadra R. Kotamarthi, Ramesh Balakrishnan, Joel W. Cline, Michael C. Robinson, and Shreyas Ananthan
Wind Energ. Sci., 3, 589–613, https://doi.org/10.5194/wes-3-589-2018, https://doi.org/10.5194/wes-3-589-2018, 2018
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This paper validates the use of idealized large-eddy simulations with periodic lateral boundary conditions to provide boundary-layer flow quantities of interest for wind energy applications. Sensitivities to model formulation, forcing parameter values, and grid configurations were also examined, both to ascertain the robustness of the technique and to characterize inherent uncertainties, as required for the evaluation of more general wind plant flow simulation approaches under development.
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.
Jens-Uwe Grooß, Rolf Müller, Reinhold Spang, Ines Tritscher, Tobias Wegner, Martyn P. Chipperfield, Wuhu Feng, Douglas E. Kinnison, and Sasha Madronich
Atmos. Chem. Phys., 18, 8647–8666, https://doi.org/10.5194/acp-18-8647-2018, https://doi.org/10.5194/acp-18-8647-2018, 2018
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We investigate a discrepancy between model simulations and observations of HCl in the dark polar stratosphere. In early winter, the less-well-studied period of the onset of chlorine activation, observations show a much faster depletion of HCl than simulations of three models. This points to some unknown process that is currently not represented in the models. Various hypotheses for potential causes are investigated that partly reduce the discrepancy. The impact on polar ozone depletion is low.
Miguel Zavala, Luisa T. Molina, Pablo Maiz, Israel Monsivais, Judith C. Chow, John G. Watson, Jose Luis Munguia, Beatriz Cardenas, Edward C. Fortner, Scott C. Herndon, Joseph R. Roscioli, Charles E. Kolb, and Walter B. Knighton
Atmos. Chem. Phys., 18, 6023–6037, https://doi.org/10.5194/acp-18-6023-2018, https://doi.org/10.5194/acp-18-6023-2018, 2018
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Black carbon, organic carbon, and co-pollutant emissions and energy efficiency from two traditional brick kilns and one MK2 kiln in Mexico were quantified using tracer ratio and sampling probe techniques. Both techniques captured similar temporal profiles of the kiln emissions and produced comparable emission factors; the MK2 generated lower emissions and higher energy efficiency. This study contributes to the limited database of brick production emissions useful for assessing their impact.
Riinu Ots, Mathew R. Heal, Dominique E. Young, Leah R. Williams, James D. Allan, Eiko Nemitz, Chiara Di Marco, Anais Detournay, Lu Xu, Nga L. Ng, Hugh Coe, Scott C. Herndon, Ian A. Mackenzie, David C. Green, Jeroen J. P. Kuenen, Stefan Reis, and Massimo Vieno
Atmos. Chem. Phys., 18, 4497–4518, https://doi.org/10.5194/acp-18-4497-2018, https://doi.org/10.5194/acp-18-4497-2018, 2018
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The main hypothesis of this paper is that people who live in large cities in the UK disobey the
smoke control lawas it has not been actively enforced for decades now. However, the use of wood in residential heating has increased, partly due to renewable energy targets, but also for discretionary (i.e. pleasant fireplaces) reasons. Our study is based mainly in London, but similar struggles with urban air quality due to residential wood and coal burning are seen in other major European cities.
Miguel Zavala, Luisa T. Molina, Tara I. Yacovitch, Edward C. Fortner, Joseph R. Roscioli, Cody Floerchinger, Scott C. Herndon, Charles E. Kolb, Walter B. Knighton, Victor Hugo Paramo, Sergio Zirath, José Antonio Mejía, and Aron Jazcilevich
Atmos. Chem. Phys., 17, 15293–15305, https://doi.org/10.5194/acp-17-15293-2017, https://doi.org/10.5194/acp-17-15293-2017, 2017
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Emission factors of black carbon and other chemically speciated particulate matter and gaseous pollutants were measured in real-world driving conditions for 20 diesel vehicles with multiple emission technologies in Mexico City using a mobile laboratory and a remote sensing technique. The results demonstrated the need to use locally obtained emissions data for diesel vehicles, especially in the developing world, to reduce uncertainty and improve the effectiveness of mitigation measures.
Stephen Conley, Ian Faloona, Shobhit Mehrotra, Maxime Suard, Donald H. Lenschow, Colm Sweeney, Scott Herndon, Stefan Schwietzke, Gabrielle Pétron, Justin Pifer, Eric A. Kort, and Russell Schnell
Atmos. Meas. Tech., 10, 3345–3358, https://doi.org/10.5194/amt-10-3345-2017, https://doi.org/10.5194/amt-10-3345-2017, 2017
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This paper describes a new method of quantifying surface trace gas emissions (e.g. methane) from small aircraft (e.g. Mooney, Cessna) in about 30 min. This technique greatly enhances our ability to rapidly respond in the event of catastrophic failures such as Aliso Canyon and Deep Water Horizon.
Jakob Lindaas, Delphine K. Farmer, Ilana B. Pollack, Andrew Abeleira, Frank Flocke, Rob Roscioli, Scott Herndon, and Emily V. Fischer
Atmos. Chem. Phys., 17, 10691–10707, https://doi.org/10.5194/acp-17-10691-2017, https://doi.org/10.5194/acp-17-10691-2017, 2017
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Wildfire smoke is becoming increasingly important for air quality in the US. We used measurements taken during the summer 2015 near Denver, CO, to provide a case study of how wildfire smoke can impact air quality, specifically ozone, which is harmful to humans. Wildfire smoke during this time period was associated with about 15 % more ozone than we would expect under normal conditions. This smoke came from fires in the Pacific Northwest and likely impacted much of the central and western US.
Mithu Debnath, G. Valerio Iungo, Ryan Ashton, W. Alan Brewer, Aditya Choukulkar, Ruben Delgado, Julie K. Lundquist, William J. Shaw, James M. Wilczak, and Daniel Wolfe
Atmos. Meas. Tech., 10, 431–444, https://doi.org/10.5194/amt-10-431-2017, https://doi.org/10.5194/amt-10-431-2017, 2017
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Triple RHI scans were performed with three simultaneous scanning Doppler wind lidars and assessed with lidar profiler and sonic anemometer data. This test is part of the XPIA experiment. The scan strategy consists in two lidars performing co-planar RHI scans, while a third lidar measures the transversal velocity component. The results show that horizontal velocity and wind direction are measured with good accuracy, while the vertical velocity is typically measured with a significant error.
Katherine R. Travis, Daniel J. Jacob, Jenny A. Fisher, Patrick S. Kim, Eloise A. Marais, Lei Zhu, Karen Yu, Christopher C. Miller, Robert M. Yantosca, Melissa P. Sulprizio, Anne M. Thompson, Paul O. Wennberg, John D. Crounse, Jason M. St. Clair, Ronald C. Cohen, Joshua L. Laughner, Jack E. Dibb, Samuel R. Hall, Kirk Ullmann, Glenn M. Wolfe, Illana B. Pollack, Jeff Peischl, Jonathan A. Neuman, and Xianliang Zhou
Atmos. Chem. Phys., 16, 13561–13577, https://doi.org/10.5194/acp-16-13561-2016, https://doi.org/10.5194/acp-16-13561-2016, 2016
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Ground-level ozone pollution in the Southeast US involves complex chemistry driven by anthropogenic emissions of nitrogen oxides (NOx) and biogenic emissions of isoprene. We find that US NOx emissions are overestimated nationally by as much as 50 % and that reducing model emissions by this amount results in good agreement with SEAC4RS aircraft measurements in August and September 2013. Observations of nitrate wet deposition fluxes and satellite NO2 columns further support this result.
Luke D. Schiferl, Colette L. Heald, Martin Van Damme, Lieven Clarisse, Cathy Clerbaux, Pierre-François Coheur, John B. Nowak, J. Andrew Neuman, Scott C. Herndon, Joseph R. Roscioli, and Scott J. Eilerman
Atmos. Chem. Phys., 16, 12305–12328, https://doi.org/10.5194/acp-16-12305-2016, https://doi.org/10.5194/acp-16-12305-2016, 2016
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This study combines new observations and a simulation to assess the interannual variability of atmospheric ammonia concentrations over the United States. The model generally underrepresents the observed variability. Nearly two-thirds of the simulated variability is caused by meteorology, twice that caused by regulations on fossil fuel combustion emissions. Adding ammonia emissions variability does not substantially improve the simulation and has little impact on summer particle concentrations.
Kennedy T. Vu, Justin H. Dingle, Roya Bahreini, Patrick J. Reddy, Eric C. Apel, Teresa L. Campos, Joshua P. DiGangi, Glenn S. Diskin, Alan Fried, Scott C. Herndon, Alan J. Hills, Rebecca S. Hornbrook, Greg Huey, Lisa Kaser, Denise D. Montzka, John B. Nowak, Sally E. Pusede, Dirk Richter, Joseph R. Roscioli, Glen W. Sachse, Stephen Shertz, Meghan Stell, David Tanner, Geoffrey S. Tyndall, James Walega, Peter Weibring, Andrew J. Weinheimer, Gabriele Pfister, and Frank Flocke
Atmos. Chem. Phys., 16, 12039–12058, https://doi.org/10.5194/acp-16-12039-2016, https://doi.org/10.5194/acp-16-12039-2016, 2016
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In this manuscript, we report on airborne measurements of non-refractory composition and optical extinction along with relevant trace gases during a unique surface mesoscale circulation event, namely the Denver Cyclone, in Colorado, USA, during in July–August 2014. The focus of this paper is to investigate how meteorological conditions associated with the Denver Cyclone impacted air quality of the Colorado Front Range.
Justin H. Dingle, Kennedy Vu, Roya Bahreini, Eric C. Apel, Teresa L. Campos, Frank Flocke, Alan Fried, Scott Herndon, Alan J. Hills, Rebecca S. Hornbrook, Greg Huey, Lisa Kaser, Denise D. Montzka, John B. Nowak, Mike Reeves, Dirk Richter, Joseph R. Roscioli, Stephen Shertz, Meghan Stell, David Tanner, Geoff Tyndall, James Walega, Petter Weibring, and Andrew Weinheimer
Atmos. Chem. Phys., 16, 11207–11217, https://doi.org/10.5194/acp-16-11207-2016, https://doi.org/10.5194/acp-16-11207-2016, 2016
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The focus of this paper was to use gas-phase tracers and aerosol composition to characterize the influence of the different sources on optical extinction (RH = 22 %) and summertime visibility in the Colorado Front Range. Our analysis indicates that aerosol nitrate contributed significantly to optical extinction in agriculturally influenced air masses, while in other plumes, organics could explain most of the observed variability in optical extinction.
Alma Hodzic, Prasad S. Kasibhatla, Duseong S. Jo, Christopher D. Cappa, Jose L. Jimenez, Sasha Madronich, and Rokjin J. Park
Atmos. Chem. Phys., 16, 7917–7941, https://doi.org/10.5194/acp-16-7917-2016, https://doi.org/10.5194/acp-16-7917-2016, 2016
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The global budget and spatial distribution of secondary organic aerosol (SOA) are highly uncertain in chemistry-climate models, which reflects our inability to characterize all phases of the OA lifecycle. We have performed global model simulations with the newly proposed formation and removal processes (photolysis and heterogeneous chemistry) and shown that SOA is a far more dynamic system, with 4 times stronger production rates and more efficient removal mechanisms, than assumed in models.
Riinu Ots, Dominique E. Young, Massimo Vieno, Lu Xu, Rachel E. Dunmore, James D. Allan, Hugh Coe, Leah R. Williams, Scott C. Herndon, Nga L. Ng, Jacqueline F. Hamilton, Robert Bergström, Chiara Di Marco, Eiko Nemitz, Ian A. Mackenzie, Jeroen J. P. Kuenen, David C. Green, Stefan Reis, and Mathew R. Heal
Atmos. Chem. Phys., 16, 6453–6473, https://doi.org/10.5194/acp-16-6453-2016, https://doi.org/10.5194/acp-16-6453-2016, 2016
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This study investigates the contribution of diesel vehicle emissions to organic aerosol formation and particulate matter concentrations in London. Comparisons of simulated pollutant concentrations with observations show good agreement and give confidence in the skill of the model applied. The contribution of diesel vehicle emissions, which are currently not included in official emissions inventories, is demonstrated to be substantial, indicating that more research on this topic is required.
Hyun Cheol Kim, Pius Lee, Laura Judd, Li Pan, and Barry Lefer
Geosci. Model Dev., 9, 1111–1123, https://doi.org/10.5194/gmd-9-1111-2016, https://doi.org/10.5194/gmd-9-1111-2016, 2016
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Fair comparison between satellite- and modeled urban NO2 column densities is important in emission inventory evaluation and regulation policy making. This study focuses on the impact of satellite footprint resolution geometry. Since OMI NO2 pixels are too coarse to resolve fine-scale urban plumes, it may cause 20–30 % bias over major cities. We introduce approaches to adjust spatial and vertical structure (downscaling & averaging kernel), and demonstrate improved agreement between sat. and model.
Xiangshang Li, Yunsoo Choi, Beata Czader, Anirban Roy, Hyuncheol Kim, Barry Lefer, and Shuai Pan
Atmos. Chem. Phys., 16, 3127–3144, https://doi.org/10.5194/acp-16-3127-2016, https://doi.org/10.5194/acp-16-3127-2016, 2016
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We performed a a month-long sensitivity study of obs-nudging on meteorology and ozone chemistry. Notable increases in temperature and wind performance were observed after obs-nudging with hourly nudging files. PBL height also matched better in the sensitivity case. The model ozone improved at ground level and aloft but to a lesser degree. An examination of a high ozone episode showed that the current nudging process does not perform consistently – quite well at times while poor at other times.
Y. S. La, M. Camredon, P. J. Ziemann, R. Valorso, A. Matsunaga, V. Lannuque, J. Lee-Taylor, A. Hodzic, S. Madronich, and B. Aumont
Atmos. Chem. Phys., 16, 1417–1431, https://doi.org/10.5194/acp-16-1417-2016, https://doi.org/10.5194/acp-16-1417-2016, 2016
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The potential impact of chamber walls on the loss of gaseous organic species and secondary organic aerosol (SOA) formation has been explored using the GECKO-A modeling tool, which explicitly represents SOA formation and gas-wall partitioning. The model was compared with 41 smog chamber experiments of SOA formation under OH oxidation of alkane and alkene serie. The organic vapor loss to the chamber walls is found to affect SOA yields as well as the composition of the gas and the particle phase.
L. Xu, L. R. Williams, D. E. Young, J. D. Allan, H. Coe, P. Massoli, E. Fortner, P. Chhabra, S. Herndon, W. A. Brooks, J. T. Jayne, D. R. Worsnop, A. C. Aiken, S. Liu, K. Gorkowski, M. K. Dubey, Z. L. Fleming, S. Visser, A. S. H. Prévôt, and N. L. Ng
Atmos. Chem. Phys., 16, 1139–1160, https://doi.org/10.5194/acp-16-1139-2016, https://doi.org/10.5194/acp-16-1139-2016, 2016
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We investigate the spatial distribution of submicron aerosol in the greater London area as part of the Clean Air for London (ClearfLo) project in winter 2012. Although the concentrations of organic aerosol (OA) are similar between a rural and an urban site, the OA sources are different. We also examine the volatility of submicron aerosol at the rural site and find that the non-volatile organics have similar sources or have undergone similar chemical processing as refractory black carbon.
A. J. Beyersdorf, L. D. Ziemba, G. Chen, C. A. Corr, J. H. Crawford, G. S. Diskin, R. H. Moore, K. L. Thornhill, E. L. Winstead, and B. E. Anderson
Atmos. Chem. Phys., 16, 1003–1015, https://doi.org/10.5194/acp-16-1003-2016, https://doi.org/10.5194/acp-16-1003-2016, 2016
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Airborne measurements in Baltimore-Washington, DC allow for an understanding of the relationship between aerosol extinction which can be measured by satellites and aerosol mass used for air quality monitoring. Extinction was found to be driven to first order by aerosol loadings; however, humidity-driven aerosol hydration plays an important secondary role. Spatial and diurnal variability in aerosol composition were small, but day-to-day variability in aerosol hygroscopicity must be accounted for.
C. E. Jordan, B. E. Anderson, A. J. Beyersdorf, C. A. Corr, J. E. Dibb, M. E. Greenslade, R. F. Martin, R. H. Moore, E. Scheuer, M. A. Shook, K. L. Thornhill, D. Troop, E. L. Winstead, and L. D. Ziemba
Atmos. Meas. Tech., 8, 4755–4771, https://doi.org/10.5194/amt-8-4755-2015, https://doi.org/10.5194/amt-8-4755-2015, 2015
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We describe a new instrument developed to observe ambient atmospheric aerosol extinction spectra from 300 to 700nm. Laboratory tests were performed to demonstrate that the instrument compares well with theoretical calculations over that spectral range, as well as with commercially available instrumentation measuring aerosol extinction at three visible wavelengths. The unique spectral data will be used to explore linkages between ambient aerosol optical properties, chemistry, and microphysics.
K. D. Custard, C. R. Thompson, K. A. Pratt, P B. Shepson, J. Liao, L. G. Huey, J. J. Orlando, A. J. Weinheimer, E. Apel, S. R. Hall, F. Flocke, L. Mauldin, R. S. Hornbrook, D. Pöhler, S. General, J. Zielcke, W. R. Simpson, U. Platt, A. Fried, P. Weibring, B. C. Sive, K. Ullmann, C. Cantrell, D. J. Knapp, and D. D. Montzka
Atmos. Chem. Phys., 15, 10799–10809, https://doi.org/10.5194/acp-15-10799-2015, https://doi.org/10.5194/acp-15-10799-2015, 2015
C. R. Thompson, P. B. Shepson, J. Liao, L. G. Huey, E. C. Apel, C. A. Cantrell, F. Flocke, J. Orlando, A. Fried, S. R. Hall, R. S. Hornbrook, D. J. Knapp, R. L. Mauldin III, D. D. Montzka, B. C. Sive, K. Ullmann, P. Weibring, and A. Weinheimer
Atmos. Chem. Phys., 15, 9651–9679, https://doi.org/10.5194/acp-15-9651-2015, https://doi.org/10.5194/acp-15-9651-2015, 2015
A. Hodzic, S. Madronich, P. S. Kasibhatla, G. Tyndall, B. Aumont, J. L. Jimenez, J. Lee-Taylor, and J. Orlando
Atmos. Chem. Phys., 15, 9253–9269, https://doi.org/10.5194/acp-15-9253-2015, https://doi.org/10.5194/acp-15-9253-2015, 2015
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Our study combines process and global chemistry modeling to investigate the potential effect of gas- and particle-phase organic photolysis reactions on the formation and lifetime of secondary organic aerosols (SOAs). Photolysis of the oxidation intermediates that partition between gas and particle phases to form SOA is not included in 3D models. Our results suggest that exposure to UV light can suppress the formation of SOA or even lead to its substantial loss (comparable to wet deposition).
L. K. Emmons, S. R. Arnold, S. A. Monks, V. Huijnen, S. Tilmes, K. S. Law, J. L. Thomas, J.-C. Raut, I. Bouarar, S. Turquety, Y. Long, B. Duncan, S. Steenrod, S. Strode, J. Flemming, J. Mao, J. Langner, A. M. Thompson, D. Tarasick, E. C. Apel, D. R. Blake, R. C. Cohen, J. Dibb, G. S. Diskin, A. Fried, S. R. Hall, L. G. Huey, A. J. Weinheimer, A. Wisthaler, T. Mikoviny, J. Nowak, J. Peischl, J. M. Roberts, T. Ryerson, C. Warneke, and D. Helmig
Atmos. Chem. Phys., 15, 6721–6744, https://doi.org/10.5194/acp-15-6721-2015, https://doi.org/10.5194/acp-15-6721-2015, 2015
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Eleven 3-D tropospheric chemistry models have been compared and evaluated with observations in the Arctic during the International Polar Year (IPY 2008). Large differences are seen among the models, particularly related to the model chemistry of volatile organic compounds (VOCs) and reactive nitrogen (NOx, PAN, HNO3) partitioning. Consistency among the models in the underestimation of CO, ethane and propane indicates the emission inventory is too low for these compounds.
J. R. Roscioli, T. I. Yacovitch, C. Floerchinger, A. L. Mitchell, D. S. Tkacik, R. Subramanian, D. M. Martinez, T. L. Vaughn, L. Williams, D. Zimmerle, A. L. Robinson, S. C. Herndon, and A. J. Marchese
Atmos. Meas. Tech., 8, 2017–2035, https://doi.org/10.5194/amt-8-2017-2015, https://doi.org/10.5194/amt-8-2017-2015, 2015
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This report presents an overview and detailed description of the measurement methods, analysis approach, and example data from a 10-week EDF-sponsored field campaign measuring methane emissions from natural gas gathering and processing facilities across the US. The dual-tracer ratio method was employed to quantify methane release rates and identify emission sources at a wide variety of facilities, using downwind measurements of CH4, C2H6, CO2, and CO with N2O and C2H2 as tracers.
J. W. Taylor, J. D. Allan, D. Liu, M. Flynn, R. Weber, X. Zhang, B. L. Lefer, N. Grossberg, J. Flynn, and H. Coe
Atmos. Meas. Tech., 8, 1701–1718, https://doi.org/10.5194/amt-8-1701-2015, https://doi.org/10.5194/amt-8-1701-2015, 2015
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When using the SP2 to report black carbon core/shell coating thickness, the core density and refractive index must be estimated from literature values. We systematically vary the assumed parameters and the instrument calibration, and quantify the effects in the derived coatings. The technique is highly sensitive to the core refractive index but has only a minor sensitivity to the core density and coating refractive index. We identify the most appropriate values to use in future analysis.
S. Visser, J. G. Slowik, M. Furger, P. Zotter, N. Bukowiecki, R. Dressler, U. Flechsig, K. Appel, D. C. Green, A. H. Tremper, D. E. Young, P. I. Williams, J. D. Allan, S. C. Herndon, L. R. Williams, C. Mohr, L. Xu, N. L. Ng, A. Detournay, J. F. Barlow, C. H. Halios, Z. L. Fleming, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 15, 2367–2386, https://doi.org/10.5194/acp-15-2367-2015, https://doi.org/10.5194/acp-15-2367-2015, 2015
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Ambient concentrations of trace elements with 2h time resolution were measured in three size ranges (PM10–2.5, PM2.5–1.0, PM1.0–0.3) at kerbside, urban background and rural sites in London during the ClearfLo (Clean Air for London) field campaign. Quantification of kerb and urban increments, and assessment of diurnal and weekly variability provided insight into sources governing urban air quality and the effects of urban micro-environments on human exposure.
B. A. Nault, C. Garland, S. E. Pusede, P. J. Wooldridge, K. Ullmann, S. R. Hall, and R. C. Cohen
Atmos. Meas. Tech., 8, 987–997, https://doi.org/10.5194/amt-8-987-2015, https://doi.org/10.5194/amt-8-987-2015, 2015
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We report the first atmospheric measurement of methyl peroxy nitrate (CH3O2NO2) and describe an experimental strategy to obtain NO2 observations free of methyl peroxy nitrate (CH3O2NO2). The accuracy of the CH3O2NO2 measurements are (+/- 40%) with a LOD of 15 pptv/min. We observe that CH3O2NO2 is ubiquitous in the upper troposphere with median mixing ratios of 100 to 200 pptv, and its composition to the total NOy budget is comparable to HNO3.
B. Yuan, P. R. Veres, C. Warneke, J. M. Roberts, J. B. Gilman, A. Koss, P. M. Edwards, M. Graus, W. C. Kuster, S.-M. Li, R. J. Wild, S. S. Brown, W. P. Dubé, B. M. Lerner, E. J. Williams, J. E. Johnson, P. K. Quinn, T. S. Bates, B. Lefer, P. L. Hayes, J. L. Jimenez, R. J. Weber, R. Zamora, B. Ervens, D. B. Millet, B. Rappenglück, and J. A. de Gouw
Atmos. Chem. Phys., 15, 1975–1993, https://doi.org/10.5194/acp-15-1975-2015, https://doi.org/10.5194/acp-15-1975-2015, 2015
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In this work, secondary formation of formic acid at an urban site and a site in an oil and gas production region is studied. We investigated various gas phase formation pathways of formic acid, including those recently proposed, using a box model. The contributions from aerosol-related processes, fog events and air-snow exchange to formic acid are also quantified.
B. H. Czader, Y. Choi, X. Li, S. Alvarez, and B. Lefer
Atmos. Chem. Phys., 15, 1253–1263, https://doi.org/10.5194/acp-15-1253-2015, https://doi.org/10.5194/acp-15-1253-2015, 2015
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Model simulations were performed with increased HONO emissions from mobile sources that reflect recent measurements at high-traffic urban sites. These higher emissions resulted in increased morning concentrations of HONO and OH. O3 concentrations were only marginally altered. Comparison with observed data shows that HONO morning peak concentrations are better predicted by the model when the higher emissions are utilized in the simulation.
J. Lee-Taylor, A. Hodzic, S. Madronich, B. Aumont, M. Camredon, and R. Valorso
Atmos. Chem. Phys., 15, 595–615, https://doi.org/10.5194/acp-15-595-2015, https://doi.org/10.5194/acp-15-595-2015, 2015
Y. You, V. P. Kanawade, J. A. de Gouw, A. B. Guenther, S. Madronich, M. R. Sierra-Hernández, M. Lawler, J. N. Smith, S. Takahama, G. Ruggeri, A. Koss, K. Olson, K. Baumann, R. J. Weber, A. Nenes, H. Guo, E. S. Edgerton, L. Porcelli, W. H. Brune, A. H. Goldstein, and S.-H. Lee
Atmos. Chem. Phys., 14, 12181–12194, https://doi.org/10.5194/acp-14-12181-2014, https://doi.org/10.5194/acp-14-12181-2014, 2014
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Amiens play important roles in atmospheric secondary aerosol formation and human health, but the fast response measurements of amines are lacking. Here we show measurements in a southeastern US forest and a moderately polluted midwestern site. Our results show that gas to particle conversion is an important process that controls ambient amine concentrations and that biomass burning is an important source of amines.
T. R. Dallmann, T. B. Onasch, T. W. Kirchstetter, D. R. Worton, E. C. Fortner, S. C. Herndon, E. C. Wood, J. P. Franklin, D. R. Worsnop, A. H. Goldstein, and R. A. Harley
Atmos. Chem. Phys., 14, 7585–7599, https://doi.org/10.5194/acp-14-7585-2014, https://doi.org/10.5194/acp-14-7585-2014, 2014
R. Kumar, M. C. Barth, S. Madronich, M. Naja, G. R. Carmichael, G. G. Pfister, C. Knote, G. P. Brasseur, N. Ojha, and T. Sarangi
Atmos. Chem. Phys., 14, 6813–6834, https://doi.org/10.5194/acp-14-6813-2014, https://doi.org/10.5194/acp-14-6813-2014, 2014
A. J. Scarino, M. D. Obland, J. D. Fast, S. P. Burton, R. A. Ferrare, C. A. Hostetler, L. K. Berg, B. Lefer, C. Haman, J. W. Hair, R. R. Rogers, C. Butler, A. L. Cook, and D. B. Harper
Atmos. Chem. Phys., 14, 5547–5560, https://doi.org/10.5194/acp-14-5547-2014, https://doi.org/10.5194/acp-14-5547-2014, 2014
G. M. Wolfe, C. Cantrell, S. Kim, R. L. Mauldin III, T. Karl, P. Harley, A. Turnipseed, W. Zheng, F. Flocke, E. C. Apel, R. S. Hornbrook, S. R. Hall, K. Ullmann, S. B. Henry, J. P. DiGangi, E. S. Boyle, L. Kaser, R. Schnitzhofer, A. Hansel, M. Graus, Y. Nakashima, Y. Kajii, A. Guenther, and F. N. Keutsch
Atmos. Chem. Phys., 14, 4715–4732, https://doi.org/10.5194/acp-14-4715-2014, https://doi.org/10.5194/acp-14-4715-2014, 2014
T. P. Riedel, G. M. Wolfe, K. T. Danas, J. B. Gilman, W. C. Kuster, D. M. Bon, A. Vlasenko, S.-M. Li, E. J. Williams, B. M. Lerner, P. R. Veres, J. M. Roberts, J. S. Holloway, B. Lefer, S. S. Brown, and J. A. Thornton
Atmos. Chem. Phys., 14, 3789–3800, https://doi.org/10.5194/acp-14-3789-2014, https://doi.org/10.5194/acp-14-3789-2014, 2014
C. J. Young, R. A. Washenfelder, P. M. Edwards, D. D. Parrish, J. B. Gilman, W. C. Kuster, L. H. Mielke, H. D. Osthoff, C. Tsai, O. Pikelnaya, J. Stutz, P. R. Veres, J. M. Roberts, S. Griffith, S. Dusanter, P. S. Stevens, J. Flynn, N. Grossberg, B. Lefer, J. S. Holloway, J. Peischl, T. B. Ryerson, E. L. Atlas, D. R. Blake, and S. S. Brown
Atmos. Chem. Phys., 14, 3427–3440, https://doi.org/10.5194/acp-14-3427-2014, https://doi.org/10.5194/acp-14-3427-2014, 2014
R. F. Hansen, S. M. Griffith, S. Dusanter, P. S. Rickly, P. S. Stevens, S. B. Bertman, M. A. Carroll, M. H. Erickson, J. H. Flynn, N. Grossberg, B. T. Jobson, B. L. Lefer, and H. W. Wallace
Atmos. Chem. Phys., 14, 2923–2937, https://doi.org/10.5194/acp-14-2923-2014, https://doi.org/10.5194/acp-14-2923-2014, 2014
C. D. Cappa, E. J. Williams, D. A. Lack, G. M. Buffaloe, D. Coffman, K. L. Hayden, S. C. Herndon, B. M. Lerner, S.-M. Li, P. Massoli, R. McLaren, I. Nuaaman, T. B. Onasch, and P. K. Quinn
Atmos. Chem. Phys., 14, 1337–1352, https://doi.org/10.5194/acp-14-1337-2014, https://doi.org/10.5194/acp-14-1337-2014, 2014
A. J. Beyersdorf, M. T. Timko, L. D. Ziemba, D. Bulzan, E. Corporan, S. C. Herndon, R. Howard, R. Miake-Lye, K. L. Thornhill, E. Winstead, C. Wey, Z. Yu, and B. E. Anderson
Atmos. Chem. Phys., 14, 11–23, https://doi.org/10.5194/acp-14-11-2014, https://doi.org/10.5194/acp-14-11-2014, 2014
J. L. Fry, D. C. Draper, K. J. Zarzana, P. Campuzano-Jost, D. A. Day, J. L. Jimenez, S. S. Brown, R. C. Cohen, L. Kaser, A. Hansel, L. Cappellin, T. Karl, A. Hodzic Roux, A. Turnipseed, C. Cantrell, B. L. Lefer, and N. Grossberg
Atmos. Chem. Phys., 13, 8585–8605, https://doi.org/10.5194/acp-13-8585-2013, https://doi.org/10.5194/acp-13-8585-2013, 2013
E. S. Cross, J. F. Hunter, A. J. Carrasquillo, J. P. Franklin, S. C. Herndon, J. T. Jayne, D. R. Worsnop, R. C. Miake-Lye, and J. H. Kroll
Atmos. Chem. Phys., 13, 7845–7858, https://doi.org/10.5194/acp-13-7845-2013, https://doi.org/10.5194/acp-13-7845-2013, 2013
S. M. Griffith, R. F. Hansen, S. Dusanter, P. S. Stevens, M. Alaghmand, S. B. Bertman, M. A. Carroll, M. Erickson, M. Galloway, N. Grossberg, J. Hottle, J. Hou, B. T. Jobson, A. Kammrath, F. N. Keutsch, B. L. Lefer, L. H. Mielke, A. O'Brien, P. B. Shepson, M. Thurlow, W. Wallace, N. Zhang, and X. L. Zhou
Atmos. Chem. Phys., 13, 5403–5423, https://doi.org/10.5194/acp-13-5403-2013, https://doi.org/10.5194/acp-13-5403-2013, 2013
C. Mouchel-Vallon, P. Bräuer, M. Camredon, R. Valorso, S. Madronich, H. Herrmann, and B. Aumont
Atmos. Chem. Phys., 13, 1023–1037, https://doi.org/10.5194/acp-13-1023-2013, https://doi.org/10.5194/acp-13-1023-2013, 2013
Related subject area
Subject: Radiation | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Radiative impact of improved global parameterisations of oceanic dry deposition of ozone and lightning-generated NOx
Measurements and modeling of airborne plutonium in Subarctic Finland between 1965 and 2011
Photochemical impacts of haze pollution in an urban environment
Changes in the aerosol direct radiative forcing from 2001 to 2015: observational constraints and regional mechanisms
The role of HFCs in mitigating 21st century climate change
Reducing CO2 from shipping – do non-CO2 effects matter?
The influence of snow grain size and impurities on the vertical profiles of actinic flux and associated NOx emissions on the Antarctic and Greenland ice sheets
Environmental impacts of shipping in 2030 with a particular focus on the Arctic region
Modeling the meteorological and chemical effects of secondary organic aerosols during an EUCAARI campaign
Performance of the line-by-line radiative transfer model (LBLRTM) for temperature and species retrievals: IASI case studies from JAIVEx
Ashok K. Luhar, Ian E. Galbally, and Matthew T. Woodhouse
Atmos. Chem. Phys., 22, 13013–13033, https://doi.org/10.5194/acp-22-13013-2022, https://doi.org/10.5194/acp-22-13013-2022, 2022
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Recent improvements to global parameterisations of oceanic ozone dry deposition and lightning-generated oxides of nitrogen (LNOx) have consequent impacts on earth's radiative fluxes. Uncertainty in radiative fluxes arising from uncertainty in LNOx is of significant magnitude in comparison with the
present-dayIPCC AR6 anthropogenic effective radiative forcing (ERF) due to ozone. Hence, uncertainty in LNOx needs to be explicitly addressed in relation to the GWP and ERF of anthropogenic methane.
Susanna Salminen-Paatero, Julius Vira, and Jussi Paatero
Atmos. Chem. Phys., 20, 5759–5769, https://doi.org/10.5194/acp-20-5759-2020, https://doi.org/10.5194/acp-20-5759-2020, 2020
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We measured concentrations and isotope ratios of plutonium in air filters collected in Finnish Lapland in 1965–2011. Radioactive-contamination sources were global nuclear-testing fallout and the Fukushima and SNAP-9A accidents. Both real and hypothetical nuclear accidents were studied with atmospheric-dispersion modeling. The radioactive-contamination effect on Finnish Lapland would be minor from an intended nuclear power plant and negligible from a floating nuclear reactor in the Barents Sea.
Michael Hollaway, Oliver Wild, Ting Yang, Yele Sun, Weiqi Xu, Conghui Xie, Lisa Whalley, Eloise Slater, Dwayne Heard, and Dantong Liu
Atmos. Chem. Phys., 19, 9699–9714, https://doi.org/10.5194/acp-19-9699-2019, https://doi.org/10.5194/acp-19-9699-2019, 2019
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This study, for the first time, uses combinations of aerosol and lidar data to drive an offline photolysis scheme. Absorbing species are shown to have the greatest impact on photolysis rate constants in the winter and scattering aerosol are shown to dominate responses in the summer. During haze episodes, aerosols are shown to produce a greater impact than cloud cover. The findings demonstrate the potential photochemical impacts of haze pollution in a highly polluted urban environment.
Fabien Paulot, David Paynter, Paul Ginoux, Vaishali Naik, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 13265–13281, https://doi.org/10.5194/acp-18-13265-2018, https://doi.org/10.5194/acp-18-13265-2018, 2018
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Observations show that the sunlight reflected to space by particles has decreased over the US and Europe, increased over India, and not changed over China from 2001 to 2015. These changes are attributed to different types of particles, namely sulfate over the US and Europe, and black carbon, sulfate, and nitrate over China and India. Our results suggest that the recent shift in human emissions from the US and Europe to Asia has altered their impact on the Earth's outgoing energy.
Y. Xu, D. Zaelke, G. J. M. Velders, and V. Ramanathan
Atmos. Chem. Phys., 13, 6083–6089, https://doi.org/10.5194/acp-13-6083-2013, https://doi.org/10.5194/acp-13-6083-2013, 2013
M. S. Eide, S. B. Dalsøren, Ø. Endresen, B. Samset, G. Myhre, J. Fuglestvedt, and T. Berntsen
Atmos. Chem. Phys., 13, 4183–4201, https://doi.org/10.5194/acp-13-4183-2013, https://doi.org/10.5194/acp-13-4183-2013, 2013
M. C. Zatko, T. C. Grenfell, B. Alexander, S. J. Doherty, J. L. Thomas, and X. Yang
Atmos. Chem. Phys., 13, 3547–3567, https://doi.org/10.5194/acp-13-3547-2013, https://doi.org/10.5194/acp-13-3547-2013, 2013
S. B. Dalsøren, B. H. Samset, G. Myhre, J. J. Corbett, R. Minjares, D. Lack, and J. S. Fuglestvedt
Atmos. Chem. Phys., 13, 1941–1955, https://doi.org/10.5194/acp-13-1941-2013, https://doi.org/10.5194/acp-13-1941-2013, 2013
E. Athanasopoulou, H. Vogel, B. Vogel, A. P. Tsimpidi, S. N. Pandis, C. Knote, and C. Fountoukis
Atmos. Chem. Phys., 13, 625–645, https://doi.org/10.5194/acp-13-625-2013, https://doi.org/10.5194/acp-13-625-2013, 2013
M. W. Shephard, S. A. Clough, V. H. Payne, W. L. Smith, S. Kireev, and K. E. Cady-Pereira
Atmos. Chem. Phys., 9, 7397–7417, https://doi.org/10.5194/acp-9-7397-2009, https://doi.org/10.5194/acp-9-7397-2009, 2009
Cited articles
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