Articles | Volume 13, issue 24
Atmos. Chem. Phys., 13, 12537–12547, 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 20 Dec 2013
Research article | 20 Dec 2013
Free-troposphere ozone and carbon monoxide over the North Atlantic for 2001–2011
A. Kumar et al.
B. Zhang, R. C. Owen, J. A. Perlinger, A. Kumar, S. Wu, M. Val Martin, L. Kramer, D. Helmig, and R. E. Honrath
Atmos. Chem. Phys., 14, 2267–2287,
Ka Ming Fung, Maria Val Martin, and Amos P. K. Tai
Preprint under review for BGShort summary
Fertilizer-induced ammonia detrimentally affects the environment by not only directly damaging ecosystems but also indirectly altering climate and soil fertility. To quantify these secondary impacts, we enabled a model (CESM) to simulate ammonia emission, chemical evolution, and deposition as a continuous cycle. We found that, if fertilizer use is to soar by 30 % from today's level, these counteracting impacts will result in a 23 % rise in ammonia emission and 7.3 % in food production globally.
Wei Wang, Laurens Ganzeveld, Samuel Rossabi, Jacques Hueber, and Detlev Helmig
Atmos. Chem. Phys., 20, 11287–11304,Short summary
Trees exchange with the atmosphere nitrogen oxides and ozone, affecting the tropospheric composition and consequently air quality and ecosystem health. We examined the leaf-level gas exchanges for four typical tree species (pine, maple, oak, aspen) found in northern Michigan, US. The leaves largely absorb the gases, showing little evidence of emission. We measured the uptake rates that can be used to improve model studies of the source and sink processes controlling these gases in forests.
Dean Howard, Yannick Agnan, Detlev Helmig, Yu Yang, and Daniel Obrist
Biogeosciences, 17, 4025–4042,Short summary
The Arctic tundra represents a vast store of carbon that may be broken down by microbial activity into greenhouse gases such as CO2 and CH4. Though microbes are less active in winter, the long duration of the cold season makes this period very important for carbon cycling. We show that, under conditions of warmer winter air temperatures and greater snowfall, deeper soils can remain warm enough to sustain significantly enhanced CH4 emission. This could have large implications for future climates.
Ryan J. Pound, Tomás Sherwen, Detlev Helmig, Lucy J. Carpenter, and Mat J. Evans
Atmos. Chem. Phys., 20, 4227–4239,Short summary
Ozone is an important pollutant with impacts on health and the environment. Ozone is lost to plants, land and the oceans. Loss to the ocean is slow compared to all other types of land cover and has not received as much attention. We build on previous work to more accurately model ozone loss to the ocean. We find changes in the concentration of ozone over the oceans, notably the Southern Ocean, which improves model performance.
Didier G. Leibovici, Shaun Quegan, Edward Comyn-Platt, Garry Hayman, Maria Val Martin, Mathieu Guimberteau, Arsène Druel, Dan Zhu, and Philippe Ciais
Biogeosciences, 17, 1821–1844,Short summary
Analysing the impact of environmental changes due to climate change, e.g. geographical spread of climate-sensitive infections (CSIs) and agriculture crop modelling, may require land surface modelling (LSM) to predict future land surface conditions. There are multiple LSMs to choose from. The paper proposes a multivariate spatio-temporal data science method to understand the inherent uncertainties in four LSMs and the variations between them in Nordic areas for the net primary production.
Detlev Helmig, Daniel Liptzin, Jacques Hueber, and Joel Savarino
The Cryosphere, 14, 199–209,Short summary
We present 15 months of trace gas observations from air withdrawn within the snowpack and from above the snow at Concordia Station in Antarctica. The data show occasional positive spikes, indicative of pollution from the station generator. The pollution signal can be seen in snowpack air shortly after it is observed above the snow surface, and lasting for up to several days, much longer than above the surface.
Martin Jiskra, Jeroen E. Sonke, Yannick Agnan, Detlev Helmig, and Daniel Obrist
Biogeosciences, 16, 4051–4064,Short summary
The tundra plays a pivotal role in Arctic mercury cycling by storing atmospheric mercury deposition and shuttling it to the Arctic Ocean. We used the isotopic fingerprint of mercury to investigate the processes controlling atmospheric mercury deposition. We found that the uptake of atmospheric mercury by vegetation was the major deposition source. Direct deposition to snow or soils only played a minor role. These results improve our understanding of Arctic mercury cycling.
Fang Li, Maria Val Martin, Meinrat O. Andreae, Almut Arneth, Stijn Hantson, Johannes W. Kaiser, Gitta Lasslop, Chao Yue, Dominique Bachelet, Matthew Forrest, Erik Kluzek, Xiaohong Liu, Stephane Mangeon, Joe R. Melton, Daniel S. Ward, Anton Darmenov, Thomas Hickler, Charles Ichoku, Brian I. Magi, Stephen Sitch, Guido R. van der Werf, Christine Wiedinmyer, and Sam S. Rabin
Atmos. Chem. Phys., 19, 12545–12567,Short summary
Fire emissions are critical for atmospheric composition, climate, carbon cycle, and air quality. We provide the first global multi-model fire emission reconstructions for 1700–2012, including carbon and 33 species of trace gases and aerosols, based on the nine state-of-the-art global fire models that participated in FireMIP. We also provide information on the recent status and limitations of the model-based reconstructions and identify the main uncertainty sources in their long-term changes.
Laura Gonzalez-Alonso, Maria Val Martin, and Ralph A. Kahn
Atmos. Chem. Phys., 19, 1685–1702,Short summary
The vertical distribution of fire smoke and factors that control its rise had not yet been quantified across the Amazon. We developed a satellite-based long record of smoke plume heights. We find that smoke heights are driven by many factors: vegetation, seasonality, time of day, fire intensity, and atmospheric and drought conditions. Also, drought increases fire pollution, with implications for air quality. Policies to control fires may be crucial in the future as more droughts are projected.
Shaojie Song, Hélène Angot, Noelle E. Selin, Hubert Gallée, Francesca Sprovieri, Nicola Pirrone, Detlev Helmig, Joël Savarino, Olivier Magand, and Aurélien Dommergue
Atmos. Chem. Phys., 18, 15825–15840,Short summary
Mercury is a trace metal with adverse health effects on human and wildlife. Its unique property makes it undergo long-range transport, and even remote Antarctica receives significant inputs. This paper presents the first model that aims to understand mercury behavior over the Antarctic Plateau. We find that mercury is quickly cycled between snow and air in the sunlit period, likely driven by bromine chemistry, and that several uncertain processes contribute to its behavior in the dark period.
Liye Zhu, Maria Val Martin, Luciana V. Gatti, Ralph Kahn, Arsineh Hecobian, and Emily V. Fischer
Geosci. Model Dev., 11, 4103–4116,Short summary
The evolution of smoke depends acutely on where the smoke is injected into the atmosphere. This paper presents the development and implementation of a new global biomass burning emissions injection scheme for GEOS-Chem. The new scheme is based on monthly gridded Multi-angle Imaging SpectroRadiometer (MISR) global plume-height stereoscopic observations in 2008.
Pei Hou, Shiliang Wu, Jessica L. McCarty, and Yang Gao
Atmos. Chem. Phys., 18, 8173–8182,Short summary
Atmospheric aerosols can be affected not only by emissions, but also meteorology, in particular precipitation. Analyses of the historical meteorological data based on multiple datasets show significant changes in precipitation characteristics, including precipitation intensity and frequency, over various regions around the world. We find that the precipitation changes over the past 30 years can easily lead to perturbations in atmospheric aerosols by 10 % or higher at the regional scale.
Yannick Agnan, Thomas A. Douglas, Detlev Helmig, Jacques Hueber, and Daniel Obrist
The Cryosphere, 12, 1939–1956,Short summary
In this study, we investigated mercury dynamics in an interior arctic tundra at Toolik Field Station (200 km from the Arctic Ocean) during two full snow seasons. We continuously measured atmospheric, snow gas phase, and soil pores mercury concentrations. We observed consistent concentration declines from the atmosphere to snowpack to soils, indicating that soils are continuous sinks of mercury. We suggest that interior arctic snowpacks may be negligible sources of mercury.
Bin Zhao, Kuo-Nan Liou, Yu Gu, Jonathan H. Jiang, Qinbin Li, Rong Fu, Lei Huang, Xiaohong Liu, Xiangjun Shi, Hui Su, and Cenlin He
Atmos. Chem. Phys., 18, 1065–1078,Short summary
The interactions between aerosols and ice clouds represent one of the largest uncertainties among anthropogenic forcings on climate change. We find that the responses of ice crystal effective radius, a key parameter determining ice clouds' net radiative effect, to aerosol loadings are modulated by water vapor amount and vary from a significant negative correlation in moist conditions (consistent with the “Twomey effect” for liquid clouds) to a strong positive correlation in dry conditions.
Yaoxian Huang, Shiliang Wu, Louisa J. Kramer, Detlev Helmig, and Richard E. Honrath
Atmos. Chem. Phys., 17, 14661–14674,Short summary
A global chemical transport model (GEOS-Chem) was employed to simulate surface ozone and its precursors at Summit, Greenland in the Arctic and compare them with 2-year in situ surface observations. The model performed well in simulating certain species (such as carbon monoxide and propane), but some significant discrepancies were identified for other species (e.g., nitrogen oxides, ethane, PAN, and ozone). We further investigated the exact causes for model–data biases.
Ling Qi, Qinbin Li, Daven K. Henze, Hsien-Liang Tseng, and Cenlin He
Atmos. Chem. Phys., 17, 9697–9716,Short summary
We find that Asian anthropogenic sources are the largest contributors (~ 40 %) to surface BC in spring in the Arctic, inconsistent with previous studies which repeatedly identified sources of surface BC as anthropogenic emissions from Europe and Russia. It takes 12–17 days for Asian anthropogenic emissions to be transported to the Arctic surface. Additionally, a large fraction (40–65 %) of Asian contribution is in the form of chronic pollution on 1- to 2-month timescales.
Mike J. Newland, Patricia Martinerie, Emmanuel Witrant, Detlev Helmig, David R. Worton, Chris Hogan, William T. Sturges, and Claire E. Reeves
Atmos. Chem. Phys., 17, 8269–8283,Short summary
We report increasing levels of alkyl nitrates in the Northern Hemisphere atmosphere between 1960 and the mid-1990s. These increases are symptomatic of large-scale changes to the chemical composition of the atmosphere, particularly with regards to the amounts of short-lived, reactive species. The observed increases are likely driven by increasing levels of nitrogen oxides. These changes have direct implications for the lifetimes of climate-relevant species in the atmosphere, such as methane.
Ling Qi, Qinbin Li, Cenlin He, Xin Wang, and Jianping Huang
Atmos. Chem. Phys., 17, 7459–7479,Short summary
Black carbon (BC) is the second only to CO2 in heating the planet, but the simulation of BC is associated with large uncertainties. BC burden is largely underestimated over land and overestimated over ocean. Our study finds that a missing process in current Wegener–Bergeron–Findeisen models largely explains the discrepancy in BC simulation over land. We call for more observations of BC in mixed-phase clouds to understand this process and improve the simulation of global BC.
Ling Qi, Qinbin Li, Yinrui Li, and Cenlin He
Atmos. Chem. Phys., 17, 1037–1059,Short summary
The Arctic is the most vulnerable region for climate change. Black carbon (BC) in air and deposited on snow and ice warms the Arctic substantially, but simulations of BC climate effects are associated with large uncertainties. To reduce this uncertainty, it is imperative to improve the simulation of BC distribution in the Arctic. We evaluate the effects of controlling factors (emissions, dry and wet deposition) on BC distribution and call for more observations to constrain these processes.
Hélène Angot, Olivier Magand, Detlev Helmig, Philippe Ricaud, Boris Quennehen, Hubert Gallée, Massimo Del Guasta, Francesca Sprovieri, Nicola Pirrone, Joël Savarino, and Aurélien Dommergue
Atmos. Chem. Phys., 16, 8249–8264,Short summary
While the Arctic has been extensively monitored, there is still much to be learned from the Antarctic continent regarding the processes that govern the budget of atmospheric mercury species. We report here the first year-round measurements of gaseous elemental mercury (Hg(0)) in the atmosphere and in snowpack interstitial air on the East Antarctic ice sheet. The striking reactivity observed on the Antarctic plateau most likely influences the cycle of atmospheric mercury on a continental scale.
Michel Legrand, Susanne Preunkert, Joël Savarino, Markus M. Frey, Alexandre Kukui, Detlev Helmig, Bruno Jourdain, Anna E. Jones, Rolf Weller, Neil Brough, and Hubert Gallée
Atmos. Chem. Phys., 16, 8053–8069,Short summary
Surface ozone, the most abundant atmospheric oxidant, has been measured since 2004 at the coastal East Antarctic site of Dumont d’Urville, and since 2007 at the Concordia station located on the high East Antarctic plateau. Long-term changes, seasonal and diurnal cycles, as well as inter-annual summer variability observed at these two East Antarctic sites are discussed. Influences like sea ice extent and outflow from inland Antarctica are discussed.
Bin Zhao, Kuo-Nan Liou, Yu Gu, Cenlin He, Wee-Liang Lee, Xing Chang, Qinbin Li, Shuxiao Wang, Hsien-Liang R. Tseng, Lai-Yung R. Leung, and Jiming Hao
Atmos. Chem. Phys., 16, 5841–5852,Short summary
We examine the impact of buildings on surface solar fluxes in Beijing by accounting for their 3-D structures. We find that inclusion of buildings changes surface solar fluxes by within ±1 W m−2, ±1–10 W m−2, and up to ±100 W m−2 at grid resolutions of 4 km, 800 m, and 90 m, respectively. We can resolve pairs of positive-negative flux deviations on different sides of buildings at ≤ 800 m resolutions. We should treat building-effect on solar fluxes differently in models with different resolutions.
Cenlin He, Qinbin Li, Kuo-Nan Liou, Ling Qi, Shu Tao, and Joshua P. Schwarz
Atmos. Chem. Phys., 16, 3077–3098,Short summary
Blarck carbon aging significantly affects its global distribution and thus climatic effects. This study develops a microphysics-based BC aging scheme in a global model, which substantially improves model simulations of BC over the remote Pacific. The microphysical scheme shows fast aging over source regions and much slower aging in remote regions. The microphysical aging significantly reduces global BC burden and lifetime, showing important implications for the estimate of BC radiative effects.
C. He, K.-N. Liou, Y. Takano, R. Zhang, M. Levy Zamora, P. Yang, Q. Li, and L. R. Leung
Atmos. Chem. Phys., 15, 11967–11980,
Y. H. Mao, Q. B. Li, D. K. Henze, Z. Jiang, D. B. A. Jones, M. Kopacz, C. He, L. Qi, M. Gao, W.-M. Hao, and K.-N. Liou
Atmos. Chem. Phys., 15, 7685–7702,
L. J. Kramer, D. Helmig, J. F. Burkhart, A. Stohl, S. Oltmans, and R. E. Honrath
Atmos. Chem. Phys., 15, 6827–6849,
S. Preunkert, M. Legrand, M. M. Frey, A. Kukui, J. Savarino, H. Gallée, M. King, B. Jourdain, W. Vicars, and D. Helmig
Atmos. Chem. Phys., 15, 6689–6705,Short summary
During two austral summers HCHO was investigated in air, snow, and interstitial air at the Concordia site located on the East Antarctic Plateau. Snow emission fluxes were estimated to be around 1 to 2 and 3 to 5 x 10^12 molecules m-2 s-1 at night and at noon, respectively. Shading experiments suggest that the photochemical HCHO production in the snowpack at Concordia remains negligible. The mean HCHO level of 130pptv observed at 1m above the surface is quite well reproduced by 1-D simulations.
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,Short summary
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.
K. Dzepina, C. Mazzoleni, P. Fialho, S. China, B. Zhang, R. C. Owen, D. Helmig, J. Hueber, S. Kumar, J. A. Perlinger, L. J. Kramer, M. P. Dziobak, M. T. Ampadu, S. Olsen, D. J. Wuebbles, and L. R. Mazzoleni
Atmos. Chem. Phys., 15, 5047–5068,Short summary
Aerosol was sampled at the Pico Mountain Observatory located at 2.2km amsl on Pico Island of the North Atlantic Azores archipelago. Two aerosol samples characterized by ultrahigh resolution mass spectrometry had biomass burning and marine emissions origins, as corroborated by collocated gas- and particle-phase measurements, air masses analyses and satellites. The paper presents the first molecular characterization of aged and processed aerosol intercepted at a remote lower free troposphere
R. Ahmadov, S. McKeen, M. Trainer, R. Banta, A. Brewer, S. Brown, P. M. Edwards, J. A. de Gouw, G. J. Frost, J. Gilman, D. Helmig, B. Johnson, A. Karion, A. Koss, A. Langford, B. Lerner, J. Olson, S. Oltmans, J. Peischl, G. Pétron, Y. Pichugina, J. M. Roberts, T. Ryerson, R. Schnell, C. Senff, C. Sweeney, C. Thompson, P. R. Veres, C. Warneke, R. Wild, E. J. Williams, B. Yuan, and R. Zamora
Atmos. Chem. Phys., 15, 411–429,Short summary
High 2013 wintertime O3 pollution events associated with oil/gas production within the Uinta Basin are studied using a 3D model. It's able quantitatively to reproduce these events using emission estimates of O3 precursors based on ambient measurements (top-down approach), but unable to reproduce them using a recent bottom-up emission inventory for the oil/gas industry. The role of various physical and meteorological processes, chemical species and pathways contributing to high O3 are quantified.
S. J. Lawson, P. W. Selleck, I. E. Galbally, M. D. Keywood, M. J. Harvey, C. Lerot, D. Helmig, and Z. Ristovski
Atmos. Chem. Phys., 15, 223–240,Short summary
Glyoxal and methylglyoxal are short-lived organic trace gases and important precursors of secondary organic aerosol. Measurements over oceans are sparse. We present the first in situ glyoxal and methylglyoxal observations over remote temperate oceans, alongside observations of precursor gases. Precursor gases cannot explain observed mixing ratios, highlighting an unknown source. We show a large discrepancy between calculated vertical column densities of glyoxal and those retrieved by satellite.
S. J. Oltmans, A. Karion, R. C. Schnell, G. Pétron, C. Sweeney, S. Wolter, D. Neff, S. A. Montzka, B. R. Miller, D. Helmig, B. J. Johnson, and J. Hueber
Atmos. Chem. Phys. Discuss.,
Revised manuscript not accepted
Y. H. Mao, Q. B. Li, D. Chen, L. Zhang, W.-M. Hao, and K.-N. Liou
Atmos. Chem. Phys., 14, 7195–7211,
C. He, Q. B. Li, K. N. Liou, J. Zhang, L. Qi, Y. Mao, M. Gao, Z. Lu, D. G. Streets, Q. Zhang, M. M. Sarin, and K. Ram
Atmos. Chem. Phys., 14, 7091–7112,
K. M. Wai, S. Wu, A. Kumar, and H. Liao
Atmos. Chem. Phys., 14, 4859–4874,
P. Boylan, D. Helmig, and J.-H. Park
Atmos. Meas. Tech., 7, 1231–1244,
H. Zhang, S. Wu, Y. Huang, and Y. Wang
Atmos. Chem. Phys., 14, 4079–4086,
B. Zhang, R. C. Owen, J. A. Perlinger, A. Kumar, S. Wu, M. Val Martin, L. Kramer, D. Helmig, and R. E. Honrath
Atmos. Chem. Phys., 14, 2267–2287,
D. Helmig, V. Petrenko, P. Martinerie, E. Witrant, T. Röckmann, A. Zuiderweg, R. Holzinger, J. Hueber, C. Thompson, J. W. C. White, W. Sturges, A. Baker, T. Blunier, D. Etheridge, M. Rubino, and P. Tans
Atmos. Chem. Phys., 14, 1463–1483,
P. M. Edwards, C. J. Young, K. Aikin, J. deGouw, W. P. Dubé, F. Geiger, J. Gilman, D. Helmig, J. S. Holloway, J. Kercher, B. Lerner, R. Martin, R. McLaren, D. D. Parrish, J. Peischl, J. M. Roberts, T. B. Ryerson, J. Thornton, C. Warneke, E. J. Williams, and S. S. Brown
Atmos. Chem. Phys., 13, 8955–8971,
H. Jiang, H. Liao, H. O. T. Pye, S. Wu, L. J. Mickley, J. H. Seinfeld, and X. Y. Zhang
Atmos. Chem. Phys., 13, 7937–7960,
M. Val Martin, C. L. Heald, B. Ford, A. J. Prenni, and C. Wiedinmyer
Atmos. Chem. Phys., 13, 7429–7439,
L. Zhang, Q. B. Li, Y. Gu, K. N. Liou, and B. Meland
Atmos. Chem. Phys., 13, 7097–7114,
D. N. Bernstein, J. D. Neelin, Q. B. Li, and D. Chen
Atmos. Chem. Phys., 13, 6373–6390,
Y. Huang, S. Wu, M. K. Dubey, and N. H. F. French
Atmos. Chem. Phys., 13, 6329–6343,
P. I. Palmer, M. Parrington, J. D. Lee, A. C. Lewis, A. R. Rickard, P. F. Bernath, T. J. Duck, D. L. Waugh, D. W. Tarasick, S. Andrews, E. Aruffo, L. J. Bailey, E. Barrett, S. J.-B. Bauguitte, K. R. Curry, P. Di Carlo, L. Chisholm, L. Dan, G. Forster, J. E. Franklin, M. D. Gibson, D. Griffin, D. Helmig, J. R. Hopkins, J. T. Hopper, M. E. Jenkin, D. Kindred, J. Kliever, M. Le Breton, S. Matthiesen, M. Maurice, S. Moller, D. P. Moore, D. E. Oram, S. J. O'Shea, R. C. Owen, C. M. L. S. Pagniello, S. Pawson, C. J. Percival, J. R. Pierce, S. Punjabi, R. M. Purvis, J. J. Remedios, K. M. Rotermund, K. M. Sakamoto, A. M. da Silva, K. B. Strawbridge, K. Strong, J. Taylor, R. Trigwell, K. A. Tereszchuk, K. A. Walker, D. Weaver, C. Whaley, and J. C. Young
Atmos. Chem. Phys., 13, 6239–6261,
L. Hu, D. B. Millet, S. Y. Kim, K. C. Wells, T. J. Griffis, E. V. Fischer, D. Helmig, J. Hueber, and A. J. Curtis
Atmos. Chem. Phys., 13, 3379–3392,
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)Impact of organic molecular structure on the estimation of atmospherically relevant physicochemical parametersSpatial and temporal variability in the hydroxyl (OH) radical: understanding the role of large-scale climate features and their influence on OH through its dynamical and photochemical driversAnalysis of atmospheric ammonia over South and East Asia based on the MOZART-4 model and its comparison with satellite and surface observationsAir quality and health benefits from ultra-low emission control policy indicated by continuous emission monitoring: a case study in the Yangtze River Delta region, ChinaBackground conditions for an urban greenhouse gas network in the Washington, DC, and Baltimore metropolitan regionExplicit modeling of isoprene chemical processing in polluted air masses in suburban areas of the Yangtze River Delta region: radical cycling and formation of ozone and formaldehydeEvaluation of the LOTOS-EUROS NO2 simulations using ground-based measurements and S5P/TROPOMI observations over GreeceReactive organic carbon emissions from volatile chemical productsA three-dimensional-model inversion of methyl chloroform to constrain the atmospheric oxidative capacityTechnical note: On comparing greenhouse gas emission metricsLate-spring and summertime tropospheric ozone and NO2 in western Siberia and the Russian Arctic: regional model evaluation and sensitivities10-year satellite-constrained fluxes of ammonia improve performance of chemistry transport modelsRevealing the sulfur dioxide emission reductions in China by assimilating surface observations in WRF-ChemTropospheric ozone in CMIP6 simulationsIdentifying forecast uncertainties for biogenic gases in the Po Valley related to model configuration in EURAD-IM during PEGASOS 2012Impact of reduced anthropogenic emissions during COVID-19 on air quality in IndiaA comparison of long-term trends in observations and emission inventories of NOxAttribution of the accelerating increase in atmospheric methane during 2010–2018 by inverse analysis of GOSAT observationsGlobal impact of COVID-19 restrictions on the surface concentrations of nitrogen dioxide and ozoneThe impact of inhomogeneous emissions and topography on ozone photochemistry in the vicinity of Hong Kong IslandInverse modelling of carbonyl sulfide: implementation, evaluation and implications for the global budgetInfluence of aromatics on tropospheric gas-phase compositionEmission inventory of air pollutants and chemical speciation for specific anthropogenic sources based on local measurements in the Yangtze River Delta region, ChinaPhotochemical environment over Southeast Asia primed for hazardous ozone levels with influx of nitrogen oxides from seasonal biomass burningAtmospheric-methane source and sink sensitivity analysis using Gaussian process emulationCarbon and air pollutant emissions from China's cement industry 1990–2015: trends, evolution of technologies, and driversImpact of International Shipping Emissions on Ozone and PM2.5: The Important Role of HONO and ClNO2Assessment of pre-industrial to present-day anthropogenic climate forcing in UKESM1Technical note: A high-resolution inverse modelling technique for estimating surface CO2 fluxes based on the NIES-TM–FLEXPART coupled transport model and its adjointImprovement of the satellite-derived NOx emissions on air quality modeling and its effect on ozone and secondary inorganic aerosol formation in the Yangtze River Delta, ChinaAircraft-based inversions quantify the importance of wetlands and livestock for Upper Midwest methane emissionsTime-resolved emission reductions for atmospheric chemistry modelling in Europe during the COVID-19 lockdownsImpact of northern hemisphere mid-latitude anthropogenic sulfur dioxide emissions on local and remote tropospheric oxidantsRapid increase in summer surface ozone over the North China Plain during 2013–2019: a side effect of particulate matter reduction control?Pan-Arctic surface ozone: modelling vs. measurementsInfluence of aerosol copper on HO2 uptake: a novel parameterized equationRole of ammonia in European air quality with changing land and ship emissions between 1990 and 2030Modelling the Impacts of Iodine Chemistry on the Northern Indian Ocean Marine Boundary LayerDiscrepancies between MICS-Asia III simulation and observation for surface ozone in the marine atmosphere over the northwestern Pacific Asian Rim regionCorrecting model biases of CO in East Asia: impact on oxidant distributions during KORUS-AQQuantifying the emission changes and associated air quality impacts during the COVID-19 pandemic on the North China Plain: a response modeling study3D simulations of tropospheric ozone depletion events using WRF-ChemDo alternative inventories converge on the spatiotemporal representation of spring ammonia emissions in France?Large and increasing methane emissions from Eastern Amazonia derived from satellite data, 2010–2018Impacts of global NOx inversions on NO2 and ozone simulationsQuantifying sources of Brazil's CH4 emissions between 2010 and 2018 from satellite dataOn the role of trend and variability in the hydroxyl radical (OH) in the global methane budgetTrends in global tropospheric hydroxyl radical and methane lifetime since 1850 from AerChemMIPEstimation of rate coefficients for the reactions of O3 with unsaturated organic compounds for use in automated mechanism constructionLong-term historical trends in air pollutant emissions in Asia: Regional Emission inventory in ASia (REAS) version 3
Gabriel Isaacman-VanWertz and Bernard Aumont
Atmos. Chem. Phys., 21, 6541–6563,Short summary
There are tens of thousands of different chemical compounds in the atmosphere. To tackle this complexity, there are a wide range of different methods to estimate their physical and chemical properties. We use these methods to understand how much the detailed structure of a molecule impacts its properties, and the extent to which properties can be estimated without knowing this level of detail. We find that structure matters, but methods lacking that level of detail still perform reasonably well.
Daniel C. Anderson, Bryan N. Duncan, Arlene M. Fiore, Colleen B. Baublitz, Melanie B. Follette-Cook, Julie M. Nicely, and Glenn M. Wolfe
Atmos. Chem. Phys., 21, 6481–6508,Short summary
We demonstrate that large-scale climate features are the primary driver of year-to-year variability in simulated values of the hydroxyl radical, the primary atmospheric oxidant, over 1980–2018. The El Niño–Southern Oscillation is the dominant mode of hydroxyl variability, resulting in large-scale global decreases in OH during El Niño events. Other climate modes, such as the Australian monsoon and the North Atlantic Oscillation, have impacts of similar magnitude but on on more localized scales.
Pooja V. Pawar, Sachin D. Ghude, Chinmay Jena, Andrea Móring, Mark A. Sutton, Santosh Kulkarni, Deen Mani Lal, Divya Surendran, Martin Van Damme, Lieven Clarisse, Pierre-François Coheur, Xuejun Liu, Gaurav Govardhan, Wen Xu, Jize Jiang, and Tapan Kumar Adhya
Atmos. Chem. Phys., 21, 6389–6409,Short summary
In this study, simulations of atmospheric ammonia (NH3) with MOZART-4 and HTAP-v2 are compared with satellite (IASI) and ground-based measurements to understand the spatial and temporal variability of NH3 over two emission hotspot regions of Asia, the IGP and the NCP. Our simulations indicate that the formation of ammonium aerosols is quicker over the NCP than the IGP, leading to smaller NH3 columns over the higher NH3-emitting NCP compared to the IGP region for comparable emissions.
Yan Zhang, Yu Zhao, Meng Gao, Xin Bo, and Chris P. Nielsen
Atmos. Chem. Phys., 21, 6411–6430,Short summary
We combined air quality and exposure response models to analyze the benefits for air quality and human health of China’s ultra-low emission policy in one of its most developed regions. Atmospheric observations and the air quality model were also used to demonstrate improvement of emission inventories incorporating online emission monitoring data. With implementation of the policy in both power and industrial sectors, the attributable deaths due to PM2.5 exposure are estimated to decrease 5.5 %.
Anna Karion, Israel Lopez-Coto, Sharon M. Gourdji, Kimberly Mueller, Subhomoy Ghosh, William Callahan, Michael Stock, Elizabeth DiGangi, Steve Prinzivalli, and James Whetstone
Atmos. Chem. Phys., 21, 6257–6273,Short summary
Estimating city emissions based on atmospheric observations requires that the portion of observed greenhouse gases that originated in the city be separated from the portion that originated outside the city, also known as the background concentration. Here, we investigate different methods to determine background concentrations for the Washington, DC, and Baltimore, MD, region and evaluate how well those methods work and the uncertainties they involve.
Kun Zhang, Ling Huang, Qing Li, Juntao Huo, Yusen Duan, Yuhang Wang, Elly Yaluk, Yangjun Wang, Qingyan Fu, and Li Li
Atmos. Chem. Phys., 21, 5905–5917,Short summary
Recently, high O3 concentrations were frequently observed in rural areas of the Yangtze River Delta (YRD) region under stagnant conditions. Using an online measurement and observation-based model, we investigated the budget of ROx radicals and the influence of isoprene chemistry on O3 formation. Our results underline that isoprene chemistry in the rural atmosphere becomes important with the participation of anthropogenic NOx.
Ioanna Skoulidou, Maria-Elissavet Koukouli, Astrid Manders, Arjo Segers, Dimitris Karagkiozidis, Myrto Gratsea, Dimitris Balis, Alkiviadis Bais, Evangelos Gerasopoulos, Trisevgeni Stavrakou, Jos van Geffen, Henk Eskes, and Andreas Richter
Atmos. Chem. Phys., 21, 5269–5288,Short summary
The performance of LOTOS-EUROS v2.2.001 regional chemical transport model NO2 simulations is investigated over Greece from June to December 2018. Comparison with in situ NO2 measurements shows a spatial correlation coefficient of 0.86, while the model underestimates the concentrations mostly during daytime (12 to 15:00 local time). Further, the simulated tropospheric NO2 columns are evaluated against ground-based MAX-DOAS NO2 measurements and S5P/TROPOMI observations for July and December 2018.
Karl M. Seltzer, Elyse Pennington, Venkatesh Rao, Benjamin N. Murphy, Madeleine Strum, Kristin K. Isaacs, and Havala O. T. Pye
Atmos. Chem. Phys., 21, 5079–5100,Short summary
Volatile chemical products (VCPs) are an increasingly important source of anthropogenic reactive organic carbon emissions. Here, we develop VCPy, a new framework to model organic emissions from VCPs throughout the United States. At the national-level, VCPy emissions are broadly consistent with the US EPA’s 2017 National Emission Inventory, however county-level and categorical estimates can differ substantially. An observational evaluation indicates high fidelity in the methods employed here.
Stijn Naus, Stephen A. Montzka, Prabir K. Patra, and Maarten C. Krol
Atmos. Chem. Phys., 21, 4809–4824,Short summary
Following up on previous box model studies, we employ a 3D transport model to estimate variations in the hydroxyl radical (OH) from observations of methyl chloroform (MCF). We derive small interannual OH variations that are consistent with variations in the El Niño–Southern Oscillation. We also find evidence for the release of MCF from oceans in atmospheric gradients of MCF. Both findings highlight the added value of a 3D transport model since box model studies did not identify these effects.
Ian Enting and Nathan Clisby
Atmos. Chem. Phys., 21, 4699–4708,Short summary
We provide a new framework for comparing short-lived greenhouse gases to long-lived greenhouse gases such as carbon dioxide using methane as an example. This can clarify the differences between various proposals that have been introduced in order to overcome the use of global warming potentials as a measure of greenhouse gas equivalence.
Thomas Thorp, Stephen R. Arnold, Richard J. Pope, Dominick V. Spracklen, Luke Conibear, Christoph Knote, Mikhail Arshinov, Boris Belan, Eija Asmi, Tuomas Laurila, Andrei I. Skorokhod, Tuomo Nieminen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 4677–4697,Short summary
We compare modelled near-surface pollutants with surface and satellite observations to better understand the controls on the regional concentrations of pollution in western Siberia for late spring and summer in 2011. We find two commonly used emission inventories underestimate human emissions when compared to observations. Transport emissions are the main source of pollutants within the region during this period, whilst fire emissions peak during June and are only significant south of 60° N.
Nikolaos Evangeliou, Yves Balkanski, Sabine Eckhardt, Anne Cozic, Martin Van Damme, Pierre-François Coheur, Lieven Clarisse, Mark W. Shephard, Karen E. Cady-Pereira, and Didier Hauglustaine
Atmos. Chem. Phys., 21, 4431–4451,Short summary
Ammonia, a substance that has played a key role in sustaining life, has been increasing in the atmosphere, affecting climate and humans. Understanding the reasons for this increase is important for the beneficial use of ammonia. The evolution of satellite products gives us the opportunity to calculate ammonia emissions easier. We calculated global ammonia emissions over the last 10 years, incorporated them into a chemistry model and recorded notable improvement in reproducing observations.
Tie Dai, Yueming Cheng, Daisuke Goto, Yingruo Li, Xiao Tang, Guangyu Shi, and Teruyuki Nakajima
Atmos. Chem. Phys., 21, 4357–4379,Short summary
The anthropogenic emission of sulfur dioxide (SO2) over China has significantly declined as a consequence of the clean air actions. We have developed a new emission inversion system to dynamically update the SO2 emission grid by grid over China by assimilating ground-based SO2 observations. The inverted SO2 emission over China in November 2016 on average had declined by 49.4 % since 2010, which is well in agreement with the bottom-up estimation of 48.0 %.
Paul T. Griffiths, Lee T. Murray, Guang Zeng, Youngsub Matthew Shin, N. Luke Abraham, Alexander T. Archibald, Makoto Deushi, Louisa K. Emmons, Ian E. Galbally, Birgit Hassler, Larry W. Horowitz, James Keeble, Jane Liu, Omid Moeini, Vaishali Naik, Fiona M. O'Connor, Naga Oshima, David Tarasick, Simone Tilmes, Steven T. Turnock, Oliver Wild, Paul J. Young, and Prodromos Zanis
Atmos. Chem. Phys., 21, 4187–4218,Short summary
We analyse the CMIP6 Historical and future simulations for tropospheric ozone, a species which is important for many aspects of atmospheric chemistry. We show that the current generation of models agrees well with observations, being particularly successful in capturing trends in surface ozone and its vertical distribution in the troposphere. We analyse the factors that control ozone and show that they evolve over the period of the CMIP6 experiments.
Annika Vogel and Hendrik Elbern
Atmos. Chem. Phys., 21, 4039–4057,Short summary
Forecasts of biogenic trace gases highly depend on the model setup and input fields. This study identifies sources of related forecast uncertainties for biogenic gases. Exceptionally high differences in both biogenic emissions and pollutant transport in the Po Valley are identified to be caused by the representation of the land surface and boundary layer dynamics. Consequently, changes in the model configuration are shown to induce significantly different local concentrations of biogenic gases.
Mengyuan Zhang, Arpit Katiyar, Shengqiang Zhu, Juanyong Shen, Men Xia, Jinlong Ma, Sri Harsha Kota, Peng Wang, and Hongliang Zhang
Atmos. Chem. Phys., 21, 4025–4037,Short summary
We studied changes in air quality in India induced by the COVID-19 lockdown through both surface observations and the CMAQ model. Our results show that emission reductions improved the air quality across India during the lockdown. On average, the levels of PM2.5 and O3 decreased by 28 % and 15 %, indicating positive effects of lockdown measures. We suggest that more stringent and localized emission control strategies should be implemented in India to mitigate air pollutions.
Elena Macdonald, Noelia Otero, and Tim Butler
Atmos. Chem. Phys., 21, 4007–4023,Short summary
NO2 limit values are still regularly exceeded in many European cities despite decreasing emissions. Measurements of NOx concentrations from stations across Europe were systematically analysed to assess long-term changes observed in urban areas. We compared trends in concentration increments to trends in total and traffic emissions to find potential discrepancies. The results can help in evaluating inaccuracies in emission inventories and in improving spatial imbalances in data availability.
Yuzhong Zhang, Daniel J. Jacob, Xiao Lu, Joannes D. Maasakkers, Tia R. Scarpelli, Jian-Xiong Sheng, Lu Shen, Zhen Qu, Melissa P. Sulprizio, Jinfeng Chang, A. Anthony Bloom, Shuang Ma, John Worden, Robert J. Parker, and Hartmut Boesch
Atmos. Chem. Phys., 21, 3643–3666,Short summary
We use 2010–2018 satellite observations of atmospheric methane to interpret the factors controlling atmospheric methane and its accelerating increase during the period. The 2010–2018 increase in global methane emissions is driven by tropical and boreal wetlands and tropical livestock (South Asia, Africa, Brazil), with an insignificant positive trend in emissions from the fossil fuel sector. The peak methane growth rates in 2014–2015 are also contributed by low OH and high fire emissions.
Christoph A. Keller, Mathew J. Evans, K. Emma Knowland, Christa A. Hasenkopf, Sruti Modekurty, Robert A. Lucchesi, Tomohiro Oda, Bruno B. Franca, Felipe C. Mandarino, M. Valeria Díaz Suárez, Robert G. Ryan, Luke H. Fakes, and Steven Pawson
Atmos. Chem. Phys., 21, 3555–3592,Short summary
This study combines surface observations and model simulations to quantify the impact of COVID-19 restrictions on air quality across the world. The presented methodology removes the confounding impacts of meteorology on air pollution. Our results indicate that surface concentrations of nitrogen dioxide, an important air pollutant emitted during the combustion of fossil fuels, declined by up to 60 % following the implementation of COVID-19 containment measures.
Yuting Wang, Yong-Feng Ma, Domingo Muñoz-Esparza, Cathy W. Y. Li, Mary Barth, Tao Wang, and Guy P. Brasseur
Atmos. Chem. Phys., 21, 3531–3553,Short summary
Large-eddy simulations (LESs) were performed in the mountainous region of the island of Hong Kong to investigate the degree to which the rates of chemical reactions between two reactive species are reduced due to the segregation of species within the convective boundary layer. We show that the inhomogeneity in emissions plays an important role in the segregation effect. Topography also has a significant influence on the segregation locally.
Jin Ma, Linda M. J. Kooijmans, Ara Cho, Stephen A. Montzka, Norbert Glatthor, John R. Worden, Le Kuai, Elliot L. Atlas, and Maarten C. Krol
Atmos. Chem. Phys., 21, 3507–3529,Short summary
Carbonyl sulfide is an important trace gas in the atmosphere and useful to estimating gross primary productivity in ecosystems, but its sources and sinks remain highly uncertain. Therefore, we applied inverse model system TM5-4DVAR to better constrain the global budget. Our finding is in line with earlier studies, pointing to missing sources in the tropics and more uptake in high latitudes. We also stress the necessity of more ground-based observations and satellite data assimilation in future.
Domenico Taraborrelli, David Cabrera-Perez, Sara Bacer, Sergey Gromov, Jos Lelieveld, Rolf Sander, and Andrea Pozzer
Atmos. Chem. Phys., 21, 2615–2636,Short summary
Atmospheric pollutants from anthropogenic activities and biomass burning are usually regarded as ozone precursors. Monocyclic aromatics are no exception. Calculations with a comprehensive atmospheric model are consistent with this view but only for air masses close to pollution source regions. However, the same model predicts that aromatics, when transported to remote areas, may effectively destroy ozone. This loss of tropospheric ozone rivals the one attributed to bromine.
Jingyu An, Yiwei Huang, Cheng Huang, Xin Wang, Rusha Yan, Qian Wang, Hongli Wang, Sheng'ao Jing, Yan Zhang, Yiming Liu, Yuan Chen, Chang Xu, Liping Qiao, Min Zhou, Shuhui Zhu, Qingyao Hu, Jun Lu, and Changhong Chen
Atmos. Chem. Phys., 21, 2003–2025,Short summary
This study established a 4 km × 4 km anthropogenic emission inventory in the Yangtze River Delta region, China, for 2017 based on locally measured emission factors and source profiles. There are high-intensity NOx and NMVOC species emissions in the eastern areas of the region. Toluene, 1,2,4-trimethylbenzene, m,p-xylene, propylene, ethylene, o-xylene, and OVOCs from industry and mobile sources have the highest comprehensive potentials for ozone and secondary organic aerosol formation.
Margaret R. Marvin, Paul I. Palmer, Barry G. Latter, Richard Siddans, Brian J. Kerridge, Mohd Talib Latif, and Md Firoz Khan
Atmos. Chem. Phys., 21, 1917–1935,Short summary
We use an atmospheric chemistry model in combination with satellite and surface observations to investigate how biomass burning affects tropospheric ozone over Southeast Asia during its fire seasons. We find that nitrogen oxides from biomass burning were responsible for about 30 % of the regional ozone formation potential, and we estimate that ozone from biomass burning caused more than 400 excess premature deaths in Southeast Asia during the peak burning months of March and September 2014.
Angharad C. Stell, Luke M. Western, Tomás Sherwen, and Matthew Rigby
Atmos. Chem. Phys., 21, 1717–1736,Short summary
Although it is the second-most important greenhouse gas, our understanding of the atmospheric-methane budget is limited. The uncertainty highlights the need for new tools to investigate sources and sinks. Here, we use a Gaussian process emulator to efficiently approximate the response of atmospheric-methane observations to changes in the most uncertain emission or loss processes. With this new method, we rigorously quantify the sensitivity of atmospheric observations to budget uncertainties.
Jun Liu, Dan Tong, Yixuan Zheng, Jing Cheng, Xinying Qin, Qinren Shi, Liu Yan, Yu Lei, and Qiang Zhang
Atmos. Chem. Phys., 21, 1627–1647,Short summary
In this study, we investigated the decadal changes in carbon dioxide and air pollutant emissions in China's cement industry for the period 1990–2015 based on intensive unit-based information. We found that from 1990 to 2015, accompanied by a 10.3-fold increase in cement production, CO2, SO2, and NOx emissions from China's cement industry increased by 627 %, 56 %, and 659 %, whereas CO, PM2.5, and PM10 emissions decreased by 9 %, 63 %, and 59 %, respectively.
Jianing Dai and Tao Wang
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
We used the WRF–Chem model with the latest HONO and ClNO2 processes to investigate their effects on the concentrations of ROx radicals, O3, and PM2.5 in Asia during summer. The results show that the ship-derived HONO and ClNO2 increased the ROx radicals concentration by two to three times and then increased the O3 and PM2.5 concentrations in marine areas. These findings indicate the importance of these nitrogen processes in the evaluation of the impact of ship emissions on air quality.
Fiona M. O'Connor, N. Luke Abraham, Mohit Dalvi, Gerd A. Folberth, Paul T. Griffiths, Catherine Hardacre, Ben T. Johnson, Ron Kahana, James Keeble, Byeonghyeon Kim, Olaf Morgenstern, Jane P. Mulcahy, Mark Richardson, Eddy Robertson, Jeongbyn Seo, Sungbo Shim, João C. Teixeira, Steven T. Turnock, Jonny Williams, Andrew J. Wiltshire, Stephanie Woodward, and Guang Zeng
Atmos. Chem. Phys., 21, 1211–1243,Short summary
This paper calculates how changes in emissions and/or concentrations of different atmospheric constituents since the pre-industrial era have altered the Earth's energy budget at the present day using a metric called effective radiative forcing. The impact of land use change is also assessed. We find that individual contributions do not add linearly, and different Earth system interactions can affect the magnitude of the calculated effective radiative forcing.
Shamil Maksyutov, Tomohiro Oda, Makoto Saito, Rajesh Janardanan, Dmitry Belikov, Johannes W. Kaiser, Ruslan Zhuravlev, Alexander Ganshin, Vinu K. Valsala, Arlyn Andrews, Lukasz Chmura, Edward Dlugokencky, László Haszpra, Ray L. Langenfelds, Toshinobu Machida, Takakiyo Nakazawa, Michel Ramonet, Colm Sweeney, and Douglas Worthy
Atmos. Chem. Phys., 21, 1245–1266,Short summary
In order to improve the top-down estimation of the anthropogenic greenhouse gas emissions, a high-resolution inverse modelling technique was developed for applications to global transport modelling of carbon dioxide and other greenhouse gases. A coupled Eulerian–Lagrangian transport model and its adjoint are combined with surface fluxes at 0.1° resolution to provide high-resolution forward simulation and inverse modelling of surface fluxes accounting for signals from emission hot spots.
Yang Yang, Yu Zhao, Lei Zhang, Jie Zhang, Xin Huang, Xuefen Zhao, Yan Zhang, Mengxiao Xi, and Yi Lu
Atmos. Chem. Phys., 21, 1191–1209,Short summary
We conducted new NOx emission estimation based on the satellite-derived NO2 column constraint and found reduced emissions compared to previous estimates for a developed region in east China. The subsequent improvement in air quality modeling was demonstrated based on available ground observations. With multiple emission reduction cases for various pollutants, we explored the effective control approaches for ozone and inorganic aerosol pollution.
Xueying Yu, Dylan B. Millet, Kelley C. Wells, Daven K. Henze, Hansen Cao, Timothy J. Griffis, Eric A. Kort, Genevieve Plant, Malte J. Deventer, Randall K. Kolka, D. Tyler Roman, Kenneth J. Davis, Ankur R. Desai, Bianca C. Baier, Kathryn McKain, Alan C. Czarnetzki, and A. Anthony Bloom
Atmos. Chem. Phys., 21, 951–971,Short summary
Methane concentrations have doubled since 1750. The US Upper Midwest is a key region contributing to such trends, but sources are poorly understood. We collected and analyzed aircraft data to resolve spatial and timing biases in wetland and livestock emission estimates and uncover errors in inventory treatment of manure management. We highlight the importance of intensive agriculture for the regional and US methane budgets and the potential for methane mitigation through improved management.
Marc Guevara, Oriol Jorba, Albert Soret, Hervé Petetin, Dene Bowdalo, Kim Serradell, Carles Tena, Hugo Denier van der Gon, Jeroen Kuenen, Vincent-Henri Peuch, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 21, 773–797,Short summary
Most European countries have imposed lockdowns to combat the spread of the COVID-19 pandemic. Such a socioeconomic disruption has resulted in a sudden drop of atmospheric emissions and air pollution levels. This study quantifies the daily reductions in national emissions and associated levels of nitrogen dioxide (NO2) due to the COVID-19 lockdowns in Europe, by making use of multiple open-access measured activity data as well as artificial intelligence and modelling techniques.
Daniel M. Westervelt, Arlene M. Fiore, Colleen B. Baublitz, and Gustavo Correa
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Particulate air pollution in the atmosphere can impact the availability of gas-phase chemical constituents, which can then have feedbacks on gas-phase air pollutants. We use a chemistry-climate computer model to simulate the impact of particulate pollution from three major world regions on gas-phase chemical constituents. We find that surface level ozone air pollution decreases by up to 5 ppbv over China in response to Chinese particulate air pollution, which has implications for policy.
Xiaodan Ma, Jianping Huang, Tianliang Zhao, Cheng Liu, Kaihui Zhao, Jia Xing, and Wei Xiao
Atmos. Chem. Phys., 21, 1–16,Short summary
The present work aims at identifying and quantifying the relative contributions of the key factors in driving a rapid increase in summertime surface O3 over the North China Plain during 2013–2019. In addition to anthropogenic emission reduction and meteorological variabilities, our study highlights the importance of inclusion of aerosol absorption and scattering properties rather than aerosol abundance only in accurate assessment of aerosol radiative effect on surface O3 formation and change.
Xin Yang, Anne-M. Blechschmidt, Kristof Bognar, Audra McClure-Begley, Sara Morris, Irina Petropavlovskikh, Andreas Richter, Henrik Skov, Kimberly Strong, David W. Tarasick, Taneil Uttal, Mika Vestenius, and Xiaoyi Zhao
Atmos. Chem. Phys., 20, 15937–15967,Short summary
This is a modelling-based study on Arctic surface ozone, with a particular focus on spring ozone depletion events (i.e. with concentrations < 10 ppbv). Model experiments show that model runs with blowing-snow-sourced sea salt aerosols implemented as a source of reactive bromine can reproduce well large-scale ozone depletion events observed in the Arctic. This study supplies modelling evidence of the proposed mechanism of reactive-bromine release from blowing snow on sea ice (Yang et al., 2008).
Huan Song, Xiaorui Chen, Keding Lu, Qi Zou, Zhaofeng Tan, Hendrik Fuchs, Alfred Wiedensohler, Daniel R. Moon, Dwayne E. Heard, María-Teresa Baeza-Romero, Mei Zheng, Andreas Wahner, Astrid Kiendler-Scharr, and Yuanhang Zhang
Atmos. Chem. Phys., 20, 15835–15850,Short summary
Accurate calculation of the HO2 uptake coefficient is one of the key parameters to quantify the co-reduction of both aerosol and ozone pollution. We modelled various lab measurements of γHO2 based on a gas-liquid phase kinetic model and developed a state-of-the-art parameterized equation. Based on a dataset from a comprehensive field campaign in the North China Plain, we proposed that the determination of the heterogeneous uptake process for HO2 should be included in future field campaigns.
Sebnem Aksoyoglu, Jianhui Jiang, Giancarlo Ciarelli, Urs Baltensperger, and André S. H. Prévôt
Atmos. Chem. Phys., 20, 15665–15680,Short summary
We investigated the role of ammonia in European air quality between 1990 and 2030 under varying land and ship emissions. If ship emissions will be regulated more strictly in the future, particulate nitrate will decrease in coastal areas in northern Europe, while sulfate aerosol will decrease in the Mediterranean region. We predict a shift in the sensitivity of aerosol formation from NH3 towards NOx emissions between 1990 and 2030 in most of Europe except the eastern part of the model domain.
Anoop S. Mahajan, Qinyi Li, Swaleha Inamdar, Kirpa Ram, Alba Badia, and Alfonso Saiz-Lopez
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Using a regional model, we show that iodine catalysed reactions cause large regional changes to the chemical composition in the northern Indian Ocean with peak changes of up to 25 % in O3, 50 % in nitrogen oxides (NO and NO2), 15 % in hydroxyl radicals (OH), 25 % in hydroperoxyl radicals (HO2), and up to a 50 % change in the nitrate radical (NO3). These results show the importance of including iodine chemistry in modelling the atmosphere in this region.
Hajime Akimoto, Tatsuya Nagashima, Natsumi Kawano, Li Jie, Joshua S. Fu, and Zifa Wang
Atmos. Chem. Phys., 20, 15003–15014,Short summary
In order to perform proper model simulation of ozone near the ground in the coastal area of northeastern Asia, it has been found that it is very important to select appropriate dry deposition velocities of ozone on the oceanic water of specific area of the northwestern Pacific. Empirical measurement of the mixing ratios and dry deposition flux of ozone over the ocean in this area is highly recommended.
Benjamin Gaubert, Louisa K. Emmons, Kevin Raeder, Simone Tilmes, Kazuyuki Miyazaki, Avelino F. Arellano Jr., Nellie Elguindi, Claire Granier, Wenfu Tang, Jérôme Barré, Helen M. Worden, Rebecca R. Buchholz, David P. Edwards, Philipp Franke, Jeffrey L. Anderson, Marielle Saunois, Jason Schroeder, Jung-Hun Woo, Isobel J. Simpson, Donald R. Blake, Simone Meinardi, Paul O. Wennberg, John Crounse, Alex Teng, Michelle Kim, Russell R. Dickerson, Hao He, Xinrong Ren, Sally E. Pusede, and Glenn S. Diskin
Atmos. Chem. Phys., 20, 14617–14647,Short summary
This study investigates carbon monoxide pollution in East Asia during spring using a numerical model, satellite remote sensing, and aircraft measurements. We found an underestimation of emission sources. Correcting the emission bias can improve air quality forecasting of carbon monoxide and other species including ozone. Results also suggest that controlling VOC and CO emissions, in addition to widespread NOx controls, can improve ozone pollution over East Asia.
Jia Xing, Siwei Li, Yueqi Jiang, Shuxiao Wang, Dian Ding, Zhaoxin Dong, Yun Zhu, and Jiming Hao
Atmos. Chem. Phys., 20, 14347–14359,Short summary
Quantifying emission changes is a prerequisite for assessment of control effectiveness in improving air quality. However, traditional bottom-up methods usually take months to perform and limit timely assessments. A novel method was developed by using a response model that provides real-time estimation of emission changes based on air quality observations. It was successfully applied to quantify emission changes on the North China Plain due to the COVID-19 pandemic shutdown.
Maximilian Herrmann, Holger Sihler, Thomas Wagner, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Three-dimensional numerical simulations of tropospheric bromine release and ozone depletion events in the Arctic polar spring of 2009 are analyzed and compared to observations. Simulation results agree well with the observations at both Utqiaġvik, Alaska and at Summit, Greenland. In a parameter study, different settings for the bromine release mechanism are evaluated. An enhancement of the bromine release mechanism is found to be beneficial for the correct prediction of the observations.
Audrey Fortems-Cheiney, Gaëlle Dufour, Karine Dufossé, Florian Couvidat, Jean-Marc Gilliot, Guillaume Siour, Matthias Beekmann, Gilles Foret, Frederik Meleux, Lieven Clarisse, Pierre-François Coheur, Martin Van Damme, Cathy Clerbaux, and Sophie Génermont
Atmos. Chem. Phys., 20, 13481–13495,Short summary
Studies have suggested the importance of ammonia emissions on pollution particle formation over Europe, whose main atmospheric source is agriculture. In this study, we performed an inter-comparison of two alternative inventories, both with a reference inventory, that quantify the French ammonia emissions during spring 2011. Over regions with large mineral fertilizer use, like over northeastern France, NH3 emissions are probably considerably underestimated by the reference inventory.
Chris Wilson, Martyn P. Chipperfield, Manuel Gloor, Robert J. Parker, Hartmut Boesch, Joey McNorton, Luciana V. Gatti, John B. Miller, Luana S. Basso, and Sarah A. Monks
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Methane (CH4) is an important greenhouse gas emitted from wetlands like those found in the basin of the Amazon River. Using an atmospheric model and observations from the GOSAT satellite, we quantified CH4 emissions from Amazonia during the previous decade. We found that the largest emissions came from a region in the eastern Basin, and that emissions there were rising faster than in other areas of South America. This finding was supported by CH4 observations made on aircraft within the Basin.
Zhen Qu, Daven K. Henze, Owen R. Cooper, and Jessica L. Neu
Atmos. Chem. Phys., 20, 13109–13130,Short summary
We use satellite observations and chemical transport modeling to quantify sources of NOx, a major air pollutant, over the past decade. We find improved simulations of the magnitude, seasonality, and trends of NO2 and ozone concentrations using these derived emissions. Changes in ozone pollution driven by human and natural sources are identified in different regions. This work shows the benefits of remote-sensing data and inverse modeling for more accurate ozone simulations.
Rachel L. Tunnicliffe, Anita L. Ganesan, Robert J. Parker, Hartmut Boesch, Nicola Gedney, Benjamin Poulter, Zhen Zhang, Jošt V. Lavrič, David Walter, Matthew Rigby, Stephan Henne, Dickon Young, and Simon O'Doherty
Atmos. Chem. Phys., 20, 13041–13067,Short summary
This study quantifies Brazil’s emissions of a potent atmospheric greenhouse gas, methane. This is in the field of atmospheric modelling and uses remotely sensed data and surface measurements of methane concentrations as well as an atmospheric transport model to interpret the data. Because of Brazil’s large emissions from wetlands, agriculture and biomass burning, these emissions affect global methane concentrations and thus are of global significance.
Yuanhong Zhao, Marielle Saunois, Philippe Bousquet, Xin Lin, Antoine Berchet, Michaela I. Hegglin, Josep G. Canadell, Robert B. Jackson, Makoto Deushi, Patrick Jöckel, Douglas Kinnison, Ole Kirner, Sarah Strode, Simone Tilmes, Edward J. Dlugokencky, and Bo Zheng
Atmos. Chem. Phys., 20, 13011–13022,Short summary
Decadal trends and variations in OH are critical for understanding atmospheric CH4 evolution. We quantify the impacts of OH trends and variations on the CH4 budget by conducting CH4 inversions on a decadal scale with an ensemble of OH fields. We find the negative OH anomalies due to enhanced fires can reduce the optimized CH4 emissions by up to 10 Tg yr−1 during El Niño years and the positive OH trend from 1986 to 2010 results in a ∼ 23 Tg yr−1 additional increase in optimized CH4 emissions.
David S. Stevenson, Alcide Zhao, Vaishali Naik, Fiona M. O'Connor, Simone Tilmes, Guang Zeng, Lee T. Murray, William J. Collins, Paul T. Griffiths, Sungbo Shim, Larry W. Horowitz, Lori T. Sentman, and Louisa Emmons
Atmos. Chem. Phys., 20, 12905–12920,Short summary
We present historical trends in atmospheric oxidizing capacity (OC) since 1850 from the latest generation of global climate models and compare these with estimates from measurements. OC controls levels of many key reactive gases, including methane (CH4). We find small model trends up to 1980, then increases of about 9 % up to 2014, disagreeing with (uncertain) measurement-based trends. Major drivers of OC trends are emissions of CH4, NOx, and CO; these will be important for future CH4 trends.
Michael E. Jenkin, Richard Valorso, Bernard Aumont, Mike J. Newland, and Andrew R. Rickard
Atmos. Chem. Phys., 20, 12921–12937,Short summary
Unsaturated organic compounds are emitted in large quantities from natural and human-influenced sources. Atmospheric removal occurs significantly by reaction with ozone, initiating reaction sequences forming free radicals and organic pollutants in the gaseous and particulate phases. Due to their very large number, it is impossible to study the reaction rate for every compound, and most have to be estimated. Updated and extended estimation methods are reported for use in atmospheric models.
Junichi Kurokawa and Toshimasa Ohara
Atmos. Chem. Phys., 20, 12761–12793,Short summary
A long historical emission inventory of major air pollutants in Asia during 1950–2015 was developed as Regional Emission inventory in ASia version 3 (REASv3). Trends of emissions and changes in source contributions in countries and regions in Asia during these 6 decades were analyzed. REASv3 provides monthly gridded data with 0.25° by 0.25° resolution for major source categories as well as table of emissions by countries and sub-regions for major sectors and fuel types.
Acker, J. G. and Leptoukh, G.: Online analysis enhances use of NASA Earth science data, Eos, Trans. Am. Geophys. Union, 88, 14–17, 2007.
Bey, I., Jacob, D. J., Yantosca, R. M., Logan, J. A., Field, B. D., Fiore, A. M., Li, Q., Liu, H. Y., Mickley, L. J., and Schultz, M. G.: Global modeling of tropospheric chemistry with assimilated meteorology: Model description and evaluation, J. Geophys. Res., 106, 023073–023096, 2001.
Bonasoni, P., Stohl, A., Cristofanelli, P., Calzolari, F., Colombo, T., and Evangelisti, F.: Background ozone variations at Mt. Cimone station, Atmos. Environ., 34, 5183–5189, 2000.
Brunke, E., Meyer, N., Lathrop, J., Johnson, B., Shadwick, D., Cuevas, E., Schmidlin, F., Tarasick, D., Claude, H., and Kerr, J.: Trends of ozone in the troposphere, Geophys. Res. Lett., 25, 139–142, 1998.
Cooper, O. R., Parrish, D. D., Stohl, A., Trainer, M., Nédélec, P., Thouret, V., Cammas, J. P., Oltmans, S. J., Johnson, B. J., and Tarasick, D.: Increasing springtime ozone mixing ratios in the free troposphere over western North America, Nature, 463, 344–348, https://doi.org/10.1038/nature08708, 2010.
Derwent, R. G., Simmonds, P. G., Seuring, S., and Dimmer, C.: Observation and interpretation of seasonal cycles in the surface concentrations of ozone and carbon monoxide at Mace Head, Ireland, from 1990 to 1994, Atmos. Environ., 32, 145–157, https://doi.org/10.1016/S1352-2310(1097)00338-00335, 1998.
Derwent, R. G., Simmonds, P. G., Manning, A. J., and Spain, T. G.: Trends over a 20-year period from 1987 to 2007 in surface ozone at the atmospheric research station, Mace Head, Ireland, Atmos. Environ., 41, 9091–9098, 2007.
Duncan, B. N. and Logan, J. A.: Model analysis of the factors regulating the trends and variability of carbon monoxide between 1988 and 1997, Atmos. Chem. Phys., 8, 7389–7403, https://doi.org/10.5194/acp-7388-7389-2008, 2008.
Duncan, B. N., Logan, J. A., Bey, I., Megretskaia, I. A., Yantosca, R. M., Novelli, P. C., Jones, N. B., and Rinsland, C. P.: Global budget of CO, 1988–1997: Source estimates and validation with a global model, J. Geophys. Res., 112, D22301, https://doi.org/10.21029/22007JD008459, 2007.
Eller, P., Singh, K., Sandu, A., Bowman, K., Henze, D. K., and Lee, M.: Implementation and evaluation of an array of chemical solvers in the Global Chemical Transport Model GEOS-Chem, Geosci. Model Dev., 2, 89–96, https://doi.org/10.5194/gmd-2-89-2009, 2009.
Evans, M. J. and Jacob, D. J.: Impact of new laboratory studies of N2O5 hydrolysis on global model budgets of tropospheric nitrogen oxides, ozone, and OH, Geophys. Res. Lett., 32, L09813, https://doi.org/10.01029/02005GL022469, 2005.
Fairlie, T. D., Jacob, D. J., and Park, R. J.: The impact of transpacific transport of mineral dust in the United States, Atmos. Environ., 41, 1251–1266, 2007.
Fiore, A. M., Jacob, D. J., Bey, I., Yantosca, R. M., Field, B. D., Fusco, A. C., and Wilkinson, J. G.: Background ozone over the United States in summer: Origin, trend, and contribution to pollution episodes, J. Geophys. Res., 107, https://doi.org/10.1029/2001JD000982, 2002.
Fisher, J. A., Jacob, D. J., Purdy, M. T., Kopacz, M., Le Sager, P., Carouge, C., Holmes, C. D., Yantosca, R. M., Batchelor, R. L., Strong, K., Diskin, G. S., Fuelberg, H. E., Holloway, J. S., Hyer, E. J., McMillan, W. W., Warner, J., Streets, D. G., Zhang, Q., Wang, Y., and Wu, S.: Source attribution and interannual variability of Arctic pollution in spring constrained by aircraft (ARCTAS, ARCPAC) and satellite (AIRS) observations of carbon monoxide, Atmos. Chem. Phys., 10, 977–996, https://doi.org/10.5194/acp-10-977-2010, 2010.
Fusco, A. C. and Logan, J. A.: Analysis of 1970–1995 trends in tropospheric ozone at Northern Hemisphere midlatitudes with the GEOS-CHEM model, J. Geophys. Res. Atmos., 108, ACH4–ACH1, https://doi.org/10.1029/2002JD002742, 2003.
González Abad, G., Allen, N., Bernath, P., Boone, C., McLeod, S., Manney, G., Toon, G., Carouge, C., Wang, Y., and Wu, S.: Ethane, ethyne and carbon monoxide concentrations in the upper troposphere and lower stratosphere from ACE and GEOS-Chem: a comparison study, Atmos. Chem. Phys., 11, 9927–9941, https://doi.org/10.5194/acp-11-9927-2011, 2011.
Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, https://doi.org/10.5194/acp-3186-3181-2006, 2006.
Guicherit, R., and Roemer, M.: Tropospheric ozone trends, Chemos.-Global Change Sci., 2, 167–183, 2000.
Heald, C. L., Jacob, D. J., Fiore, A. M., Emmons, L. K., Gille, J. C., Deeter, M. N., Warner, J., Edwards, D. P., Crawford, J. H., and Hamlin, A. J.: Asian outflow and trans-Pacific transport of carbon monoxide and ozone pollution: An integrated satellite, aircraft, and model perspective, J. Geophys. Res. Atmos., 108, 4804, https://doi.org/10.1029/2003JD003507, 2003.
Helsel, D. R. and Hirsch, R. M.: Statistical methods in water resources, US Geological survey, Reston, VA, 2002.
Holloway, T., Hiram Levy, I., and Kasibhatla, P.: Global distribution of carbon monoxide, J. Geophys. Res., 105, 12123–12112, 2000.
Honrath, R. E., Owen, R. C., Val Martin, M., Reid, J. S., Lapina, K., Fialho, P., Dziobak, M. P., Kleissl, J., and Westphal, D. L.: Regional and hemispheric impacts of anthropogenic and biomass burning emissions on summertime CO and O3 in the North Atlantic lower free troposphere, J. Geophys. Res.-Atmos., 109, D24310, https://doi.org/10.1029/2004JD005147, 2004.
Huang, Y., Wu, S., Dubey, M. K., and French, N. H. F.: Impact of aging mechanism on model simulated carbonaceous aerosols, Atmos. Chem. Phys., 13, 6329–6343, https://doi.org/10.5194/acp-13-6329-2013, 2013.
Hudman, R. C., Jacob, D. J., Turquety, S., Leibensperger, E. M., Murray, L. T., Wu, S., Gilliland, A., Avery, M., Bertram, T. H., and Brune, W.: Surface and lightning sources of nitrogen oxides over the United States: Magnitudes, chemical evolution, and outflow, J. Geophys. Res. Atmos., 112, D12S05, https://doi.org/10.1029/2006JD007912, 2007.
Hudman, R. C., Murray, L. T., Jacob, D. J., Millet, D., Turquety, S., Wu, S., Blake, D., Goldstein, A., Holloway, J., and Sachse, G.: Biogenic versus anthropogenic sources of CO in the United States, Geophys. Res. Lett., 35, L04801, https://doi.org/10.1029/2007GL032393, 2008.
Hudman, R. C., Murray, L. T., Jacob, D. J., Turquety, S., Wu, S., Millet, D. B., Avery, M., Goldstein, A. H., and Holloway, J.: North American influence on tropospheric ozone and the effects of recent emission reductions: Constraints from ICARTT observations, J. Geophys. Res. Atmos., 114, D07302, https://doi.org/10.1029/2008JD010126, 2009.
Jacob, D. J., Horowitz, L. W., Munger, J. W., Heikes, B. G., Dickerson, R. R., Artz, R. S., and Keene, W. C.: Seasonal transition from NOx-to hydrocarbon-limited conditions for ozone production over the eastern United States in September, J. Geophys. Res. Atmos., 100, 9315–9324, 1995.
Jaffe, D., Price, H., Parrish, D., Goldstein, A., and Harris, J.: Increasing background ozone during spring on the west coast of North America, Geophys. Res. Lett., 30, 1613, https://doi.org/10.1029/2003GL017024, 2003.
Johnson, C. E., Collins, W. J., Stevenson, D. S., and Derwent, R. G.: Relative roles of climate and emissions changes on future tropospheric oxidant concentrations, J. Geophys. Res. Atmos., 104, 18631–18645, 1999.
Johnson, M. S., Meskhidze, N., Solmon, F., Gassó, S., Chuang, P. Y., Gaiero, D. M., Yantosca, R. M., Wu, S., Wang, Y., and Carouge, C.: Modeling dust and soluble iron deposition to the South Atlantic Ocean, J. Geophys. Res. Atmos., 115, D15202, https://doi.org/10.1029/2009JD013311, 2010.
Khalil, M. A. K. and Rasmussen, R. A.: Global decrease in atmospheric carbon monoxide, Nature, 370, 639–641, 1994.
Kleinman, L., Lee, Y. N., Springston, S. R., Lee, J. H., Nunnermacker, L., Weinstein-Lloyd, J., Zhou, X., and Newman, L.: Peroxy radical concentration and ozone formation rate at a rural site in the southeastern United States, J. Geophys. Res., 100, 7263–7273, 1995.
Kleissl, J., Honrath, R. E., Dziobak, M. P., Tanner, D., Martin, M. V., Owen, R. C., and Helmig, D.: Occurrence of upslope flows at the Pico mountaintop observatory: A case study of orographic flows on a small, volcanic island, J. Geophys. Res., 112, D10S35, https://doi.org/10.1029/2006JD007565, 2007.
Kopacz, M., Jacob, D. J., Fisher, J. A., Logan, J. A., Zhang, L., Megretskaia, I. A., Yantosca, R. M., Singh, K., Henze, D. K., Burrows, J. P., Buchwitz, M., Khlystova, I., McMillan, W. W., Gille, J. C., Edwards, D. P., Eldering, A., Thouret, V., and Nedelec, P.: Global estimates of CO sources with high resolution by adjoint inversion of multiple satellite datasets (MOPITT, AIRS, SCIAMACHY, TES), Atmos. Chem. Phys., 10, 855–876, https://doi.org/10.5194/acp-10-855-2010, 2010.
Law, K.: More ozone over North America, Nature, 463, 307–308, 2010.
Lee, S. H., Akimoto, H., Nakane, H., Kurnosenko, S., and Kinjo, Y.: Lower tropospheric ozone trend observed in 1989–1997 at Okinawa, Japan, Geophys. Res. Lett., 25, 1637–1640, 1998.
Li, Q., Jacob, D. J., Bey, I., Palmer, P. I., Duncan, B. N., Field, B. D., Martin, R. V., Fiore, A. M., Yantosca, R. M., Parrish, D. D., Simmonds, P. G., and Oltmans, S. J.: Transatlantic transport of pollution and its effects on surface ozone in Europe and North America, J. Geophys. Res., 107, 4166, https://doi.org/10.1029/2001JD001422, 2002.
Martin, R. V., Chance, K., Jacob, D. J., Kurosu, T. P., Spurr, R. J. D., Bucsela, E., Gleason, J. F., Palmer, P. I., Bey, I., Fiore, A. M., Li, Q., Yantosca, R. M., and Koelemeijer, R. B. A.: An improved retrieval of tropospheric nitrogen dioxide from GOME, J. Geophys. Res. Atmos., 107, 4437–4456, https://doi.org/10.1029/2001JD001027, 2002.
McLinden, C. A., Olsen, S. C., Hannegan, B., Wild, O., Prather, M. J., and Sundet, J.: Stratospheric ozone in 3-D models: A simple chemistry and the cross-tropopause flux, J. Geophys. Res.-Atmos., 105, 14653–14665, https://doi.org/10.11029/12000JD900124, 2000.
McMillan, W. W., Barnet, C., Strow, L., Chahine, M. T., McCourt, M. L., Warner, J. X., Novelli, P. C., Korontzi, S., Maddy, E. S., and Datta, S.: Daily global maps of carbon monoxide from NASA's Atmospheric Infrared Sounder, Geophys. Res. Lett., 32, L11801, https://doi.org/10.11029/12004GL021821, 2005.
Olivier, J. G. J. and Berdowski, J. J. M.: Global emission sources and sinks, in The Climate System, edited by: Berdowski, J., Guicherit, R., and Heij, B. J., 33–77, Swets & Zeitlinger, Lisse, The Netherlands, 2001.
Oltmans, S. J., Lefohn, A. S., Harris, J. M., Galbally, I., Scheel, H. E., Bodeker, G., Brunke, E., Claude, H., Tarasick, D., Johnson, B. J., Simmonds, P., Shadwick, D., Anlauf, K., Hayden, K., Schmidlin, F., Fujimoto, T., Akagi, K., Meyer, C., Nichol, S., Davies, J., Redondas, A., and Cuevasa, E.: Long-term changes in tropospheric ozone, Atmos. Environ., 40, 3156–3173, 2006.
Park, R. J., Jacob, D. J., Field, B. D., Yantosca, R. M., and Chin, M.: Natural and transboundary pollution influences on sulfate-nitrate-ammonium aerosols in the United States: Implications for policy, J. Geophys. Res. Atmos., 109, D15204, https://doi.org/10.1029/2003JD004473, 2004.
Parrish, D. D., Aikin, K. C., Oltmans, S. J., Johnson, B. J., Ives, M., and Sweeny, C.: Impact of transported background ozone inflow on summertime air quality in a California ozone exceedance area, Atmos. Chem. Phys., 10, 10093–10109, https://doi.org/10.5194/acp-10-10093-2010, 2010.
Parrish, D. D., Law, K. S., Staehelin, J., Derwent, R. G., Cooper, O. R., Tanimoto, H., Volz-Thomas, A., Gilge, S., Scheel, H. E., and Steinbacher, M.: Lower tropospheric ozone at northern midlatitudes: Changing seasonal cycle, Geophys. Res. Lett., 40, 1631–1636, https://doi.org/10.1002/grl.50303, 2013.
Sandu, A. and Sander, R.: Technical note: Simulating chemical systems in Fortran90 and Matlab with the Kinetic PreProcessor KPP-2.1, Atmos. Chem. Phys., 6, 187–195, https://doi.org/10.5194/acp-6-187-2006, 2006.
Seinfeld, J. H. and Pandis, S. N.: Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, Atmospheric Chemistry and Physics, John Wiley & Sons, New York, 1326, 2006.
Streets, D. G., Bond, T. C., Carmichael, G. R., Fernandes, S. D., Fu, Q., He, D., Klimont, Z., Nelson, S. M., Tsai, N. Y., Wang, M. Q., Woo, J.-H., and Yarber, K. F.: An inventory of gaseous and primary aerosol emissions in Asia in the year 2000, J. Geophys. Res., 108, 8809, https://doi.org/10.1029/2002JD003093, 2003.
Streets, D. G., Zhang, Q., Wang, L., He, K., Hao, J., Wu, Y., Tang, Y., and Carmichael, G. R.: Revisiting China's CO emissions after the Transport and Chemical Evolution over the Pacific (TRACE-P) mission: Synthesis of inventories, atmospheric modeling, and observations, J. Geophys. Res., 111, D14306, https://doi.org/10.11029/12006JD007118, 2006.
Val Martin, M., Honrath, R. E., Owen, R. C., Pfister, G., Fialho, P., and Barata, F.: Significant enhancements of nitrogen oxides, black carbon, and ozone in the North Atlantic lower free troposphere resulting from North American boreal wildfires, J. Geophys. Res, 111, D23S60, https://doi.org/10.1029/2006JD007530, 2006.
Val Martin, M., Honrath, R. E., Owen, R. C., and Li, Q. B.: Seasonal variation of nitrogen oxides in the central North Atlantic lower free troposphere, J. Geophys. Res. Atmos., 113, D17307, https://doi.org/10.1029/2007JD009688, 2008a.
Val Martin, M., Honrath, R. E., Owen, R. C., and Lapina, K.: Large-scale impacts of anthropogenic pollution and boreal wildfires on the nitrogen oxides over the central North Atlantic region, J. Geophys. Res., 113, D17308, https://doi.org/10.11029/12007JD009689, 2008b.
van der Werf, G. R., Randerson, J. T., Giglio, L., Collatz, G. J., Kasibhatla, P. S., and Arellano Jr., A. F.: Interannual variability in global biomass burning emissions from 1997 to 2004, Atmos. Chem. Phys., 6, 3423–3441, https://doi.org/10.5194/acp-6-3423-2006, 2006.
van der Werf, G. R., Randerson, J. T., Giglio, L., Collatz, G. J., Mu, M., Kasibhatla, P. S., Morton, D. C., DeFries, R. S., Jin, Y., and van Leeuwen, T. T.: Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997–2009), Atmos. Chem. Phys., 10, 11707–11735, https://doi.org/10.5194/acp-5110-11707-12010, 2010.
Vingarzan, R.: A review of surface ozone background levels and trends, Atmos. Environ., 38, 3431–3442, 2004.
Wang, H., Jacob, D. J., Le Sager, P., Streets, D. G., Park, R. J., Gilliland, A. B., and Van Donkelaar, A.: Surface ozone background in the United States: Canadian and Mexican pollution influences, Atmos. Environ., 43, 1310–1319, 2009.
Wang, Y. and Jacob, D. J.: Anthropogenic forcing on tropospheric ozone and OH since preindustrial times, J. Geophys. Res. Atmos., 103, 31123–31135, 1998.
Wang, Y., Jacob, D. J., and Logan, J. A.: Global simulation of tropospheric O3-NOx-hydrocarbon chemistry. 1. Model formulation, J. Geophys. Res., 156, 148–227, 1998.
Wu, S., Mickley, L. J., Jacob, D. J., Logan, J. A., Yantosca, R. M., and Rind, D.: Why are there large differences between models in global budgets of tropospheric ozone?, J. Geophys. Res., 112, D05302, https://doi.org/10.01029/02006JD007801, 2007.
Wu, S., Mickley, L. J., Jacob, D. J., Rind, D., and Streets, D. G.: Effects of 2000–2050 changes in climate and emissions on global tropospheric ozone and the policy-relevant background surface ozone in the United States, J. Geophys. Res. Atmos., 113, D18312, https://doi.org/10.1029/2007JD009639, 2008a.
Wu, S., Mickley, L. J., Leibensperger, E. M., Jacob, D. J., Rind, D., and Streets, D. G.: Effects of 2000–2050 global change on ozone air quality in the United States, J. Geophys. Res., 113, D06302, https://doi.org/10.01029/02007JD009639, 2008b.
Wu, S., Mickley, L. J., Kaplan, J. O., and Jacob, D. J.: Impacts of changes in land use and land cover on atmospheric chemistry and air quality over the 21st century, Atmos. Chem. Phys., 12, 1597–1609, https://doi.org/10.5194/acp-12-1597-2012, 2012.
Yu, F., Luo, G., Bates, T. S., Anderson, B., Clarke, A., Kapustin, V., Yantosca, R. M., Wang, Y., and Wu, S.: Spatial distributions of particle number concentrations in the global troposphere: Simulations, observations, and implications for nucleation mechanisms, J. Geophys. Res., 115, D17205, https://doi.org/10.1029/2009JD013473, 2010.
Yurganov, L. N., McMillan, W. W., Dzhola, A. V., Grechko, E. I., Jones, N. B., and van der Werf, G. R.: Global AIRS and MOPITT CO measurements: Validation, comparison, and links to biomass burning variations and carbon cycle, J. Geophys. Res. Atmos., 113, D09301, https://doi.org/10.1029/2007JD009229, 2008.
Zhang, L., Jacob, D. J., Liu, X., Logan, J. A., Chance, K., Eldering, A., and Bojkov, B. R.: Intercomparison methods for satellite measurements of atmospheric composition: application to tropospheric ozone from TES and OMI, Atmos. Chem. Phys., 10, 4725–4739, https://doi.org/10.5194/acp-4710-4725-2010, 2010.
Zhang, L., Jacob, D. J., Boersma, K., Jaffe, D., Olson, J., Bowman, K., Worden, J., Thompson, A., Avery, M., and Cohen, R.: Transpacific transport of ozone pollution and the effect of recent Asian emission increases on air quality in North America: an integrated analysis using satellite, aircraft, ozonesonde, and surface observations, Atmos. Chem. Phys., 8, 6117–6136, 2008.
Zhang, Q., Streets, D. G., Carmichael, G. R., He, K. B., Huo, H., Kannari, A., Klimont, Z., Park, I. S., Reddy, S., Fu, J. S., Chen, D., Duan, L., Lei, Y., Wang, L. T., and Yao, Z. L.: Asian emissions in 2006 for the NASA INTEX-B mission, Atmos. Chem. Phys., 9, 5131–5153, https://doi.org/10.5194/acp-9-5131-2009, 2009.