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5. A 3d Regional Scale Photochemical Air Quality Model. Application to a 3 Day Summertime Episode over Paris Un modèle photochimique 3D de qualité de l'air à l'échelle régionale. Application à un épisode de 3 jours à Paris en été

Author

Carissimo B., Dupont E., Musson-Genon L., Riboud P. M., Jaecker-Voirol A., Lipphardt M., Martin B., Quandalle Ph., Salles J., Aumont B., Bergametti G., Bey I., and Toupance G.

Subjects
Chemical technology, TP1-1185, Energy industries. Energy policy. Fuel trade, HD9502-9502.5
Abstract

This paper presents AZUR, a 3D Eulerian photochemical air quality model for the simulation of air pollution in urban and semi-urban areas. The model tracks gas pollutant species emitted into the atmosphere by transportation and industrial sources, it computes the chemical reactions of these species under varying meteorological conditions (photolysis, pressure, temperature, humidity), their transport by wind and their turbulent diffusion as a function of air stability. It has a modular software structure which includes several components dedicated to specific processes :-MERCURE, a meso-scale meteorological model to compute the wind field, turbulent diffusion coefficients, and other meteorological parameters. It is a 3D regional scale model accounting for different ground types and urban densities. It includes a complete set of physical parameterizations in clear sky. -MIEL, an emission inventory model describing the pollutant fluxes from automotive transportation, domestic and industrial activities. This model includes a mobile source inventory based on road vehicle countings together with global information on transportation fluxes extracted from statistical population data. It uses specific emission factors representative of the vehicle fleet and real driving patterns. -MoCA a photochemical gas phase model describing the chemistry of ozone, NOx, and hydrocarbon compounds. This model, with 83 species and 191 reactions, is a reduced mechanism well adapted to various air quality conditions (ranging from urban to rural conditions). For interpretative reasons, the identity of primary hydrocarbons is preserved. -AIRQUAL, a 3D Eulerian model describing the transport by mean wind flux and air turbulent diffusion of species in the atmosphere, associated with a Gear type chemical equation solver. The model has been applied to a 3-day summertime episode over Paris area. Simulation results are compared to ground level concentration measurements performed by the local monitoring network (Airparif). Cet article présente AZUR, un modèle photochimique eulérien 3D de qualité de l'air pour la simulation de la pollution de l'air dans les zones urbaines et semi-urbaines. Ce modèle suit les évolutions des espèces polluantes gazeuses émises dans l'atmosphère par les transports routiers et les sources industrielles, il prend en compte les réactions chimiques auxquelles sont soumises ces espèces pour des conditions météorologiques en évolution (photolyse, pression, température, humidité), leur transport par le vent et leur diffusion turbulente en fonction de la stabilité de l'air. Le logiciel a une structure modulaire avec plusieurs composants dédiés à des processus spécifiques : -MERCURE est un modèle météorologique à moyenne échelle pour déterminer les champs de vents, les coefficients de diffusion turbulente et d'autres paramètres météorologiques. C'est un modèle 3D à l'échelle régionale qui prend en compte les différentes configurations de sols et les zones de densité urbaine. Il comprend un système complet de paramètres physiques associés à des situations de ciel dégagé. -MIEL est un modèle d'inventaire d'émissions décrivant les flux de polluants provenant des transports automobiles et des activités domestiques ou industrielles. Ce modèle comprend un inventaire des sources mobiles basé sur des comptages de véhicules sur routes associés à des informations globales sur les flux de transports déduites de données statistiques sur la population. Il utilise des facteurs d'émission spécifiques correspondant aux flottes de véhicules et à des conditions de conduites réalistes. -MoCA est un modèle photochimique en phase gazeuse décrivant la chimie de l'ozone, des NOx, et des composés hydrocarbonés. Ce modèle, avec 83 espèces et 191 réactions, correspond à un mécanisme réduit bien adapté à des conditions variées de qualité de l'air (allant de conditions en sites urbains à celles en sites ruraux). Pour des raisons de commodité d'interprétation, l'identité des hydrocarbures primaires est conservée. -AIRQUAL est un modèle eulérien 3D décrivant les phénomènes de transport par les vents et la diffusion turbulente des espèces dans l'atmosphère, il est associé à un solveur d'équations chimiques du type Gear. Le modèle a été appliqué à un épisode estival de 3 jours au-dessus de la région parisienne. Les résultats de la simulation sont comparés aux mesures de concentrations opérées par le réseau local de surveillance (Airparif).

Published
2006
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7. PERSPECTIVE ON GAS-PHASE ATMOSPHERIC CHEMICAL KINETIC MECHANISM

Author

Vereecken, L., Aumont, B., Barnes, I., Bozzelli, J.W., Goldman, M.J., Green, W.H., Madronich, S., Mcgillen, M.R., Mellouki, A., Orlando, J.J., Picquet-Varrault, B., Rickard, A.R., Stockwell, W.R., Wallington, T.J., Carter, W.P.L., Forschungszentrum Jülich GmbH, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Atmospheric Chemistry Division [Boulder], National Center for Atmospheric Research [Boulder] (NCAR), Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut des Sciences de l'Ingénierie et des Systèmes (INSIS), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), and University of Bristol [Bristol]

Subjects
[SDE.MCG]Environmental Sciences/Global Changes, ddc:540, [CHIM]Chemical Sciences
Abstract

International audience; This perspective gives our views on general aspects and future directions of gas‐phase atmospheric chemical kinetic mechanism development, emphasizing on the work needed for the sustainable development of chemically detailed mechanisms that reflect current kinetic, mechanistic, and theoretical knowledge. Current and future mechanism development efforts and research needs are discussed, including software‐aided autogeneration and maintenance of kinetic models as a future‐proof approach for atmospheric model development. There is an overarching need for the evaluation and extension of structure‐activity relationships (SARs) that predict the properties and reactions of the many multifunctionalized compounds in the atmosphere that are at the core of detailed mechanisms, but for which no direct chemical data are available. Here, we discuss the experimental and theoretical data needed to support the development of mechanisms and SARs, the types of SARs relevant to atmospheric chemistry, the current status and limitations of SARs for various types of atmospheric reactions, the status of thermochemical estimates needed for mechanism development, and our outlook for the future. The authors have recently formed a SAR evaluation working group to address these issues.

Published
2018

8. Perspective on Mechanism Development and Structure‐Activity Relationships for Gas‐Phase Atmospheric Chemistry

Author

Rickard, Andrew Robert, Vereecken, L., Aumont, B., Barnes, I, Bozzelli, J. W., Goldman, M. J., Green, W. H., Madronich, S., McGillen, M., Mellouki, A., Orlando, J. J., Wallington, Timothy J., Picquet-Varrault, B., Stockwell, W. R., and Carter, W. P. L.

Abstract

This perspective gives our views on general aspects and future directions of gas‐phase atmospheric chemical kinetic mechanism development, emphasizing on the work needed for the sustainable development of chemically detailed mechanisms that reflect current kinetic, mechanistic, and theoretical knowledge. Current and future mechanism development efforts and research needs are discussed, including software‐aided autogeneration and maintenance of kinetic models as a future‐proof approach for atmospheric model development. There is an overarching need for the evaluation and extension of structure‐activity relationships (SARs) that predict the properties and reactions of the many multifunctionalized compounds in the atmosphere that are at the core of detailed mechanisms, but for which no direct chemical data are available. Here, we discuss the experimental and theoretical data needed to support the development of mechanisms and SARs, the types of SARs relevant to atmospheric chemistry, the current status and limitations of SARs for various types of atmospheric reactions, the status of thermochemical estimates needed for mechanism development, and our outlook for the future. The authors have recently formed a SAR evaluation working group to address these issues.

Published
2018

9. Cover Image, Volume 50, Issue 6

Author

Vereecken, L., primary, Aumont, B., additional, Barnes, I., additional, Bozzelli, J.W., additional, Goldman, M.J., additional, Green, W.H., additional, Madronich, S., additional, Mcgillen, M.R., additional, Mellouki, A., additional, Orlando, J.J., additional, Picquet-Varrault, B., additional, Rickard, A.R., additional, Stockwell, W.R., additional, Wallington, T.J., additional, and Carter, W.P.L., additional

Published
2018
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10. Perspective on Mechanism Development and Structure‐Activity Relationships for Gas‐Phase Atmospheric Chemistry

Author

Vereecken, L., primary, Aumont, B., additional, Barnes, I., additional, Bozzelli, J.W., additional, Goldman, M.J., additional, Green, W.H., additional, Madronich, S., additional, Mcgillen, M.R., additional, Mellouki, A., additional, Orlando, J.J., additional, Picquet‐Varrault, B., additional, Rickard, A.R., additional, Stockwell, W.R., additional, Wallington, T.J., additional, and Carter, W.P.L., additional

Published
2018
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13. Tropospheric Aerosol: Formation, Trasformation, Fate and Impacts. General Discussion

Author

Wahner, A., Pandis, S., Allan, J., Mc Figgans, G., Abbatt, J., Freedman, M., Johnston, M., Harrison, R., Donahue, N., Percival, C., Heard, D., Carslaw, K., Jacobson, M., Olenius, T., Vehkamaki, H., Nizkorodov, S., Kiendler Scharr, A., Cappelletti, David Michele, Herrmann, H., Cox, T., Mcneill, V. F., Lewis, A., Colomer Ortega, I. K., Krieger, U., Colussi, A., Aumont, B., Kroll, J., Volkamer, R., Noziere, B., Abbat, J., Rudich, Y., Knopf, D., Held, A., and Villenave, E.

Published
2013

14. Transport and chemistry of formaldehyde by mesoscale convective systems in West Africa during AMMA 2006

Author

Borbon, A., Ruiz, M., Bechara, J., Aumont, B., Chong, M., Huntrieser, H., Mari, C., Reeves, C.E., Scialom, G., Hamburger, T., Stark, H., Afif, C., Jambert, C., Mills, G., Schlager, H., Perros, P. E., Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), DLR Institut für Physik der Atmosphäre (IPA), Deutsches Zentrum für Luft- und Raumfahrt [Oberpfaffenhofen-Wessling] (DLR), School of Environmental Sciences [Norwich], University of East Anglia [Norwich] (UEA), SPACE - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Applied Environmental Science [Stockholm] (ITM), Stockholm University, NOAA Earth System Research Laboratory (ESRL), National Oceanic and Atmospheric Administration (NOAA), Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado [Boulder]-National Oceanic and Atmospheric Administration (NOAA), Department of Chemistry [Beyrouth], Université Saint-Joseph de Beyrouth (USJ), European Community Sixth Framework Research Programme, Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'aérologie (LA), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Atmospheric chemistry, trace gases, Formaldehyde, West Africa, Atmosphärische Spurenstoffe, Cloud uptake, Tropical upper troposphere, airborne measurements, convection, Deep convection
Abstract

International audience; In situ measurements of formaldehyde (CH2O) onboard four European research aircraft in August 2006 as part of the African Monsoon Multidisciplinary Analysis (AMMA) experiment in West Africa are used (1) to examine the redistribution of CH2O by mesoscale convective systems (MCS) in the tropical upper troposphere (UT), (2) to evaluate the scavenging efficiency (SE) of CH2O by MCS and (3) to quantify the impact of CH2O on UT photooxidant production downwind of MCS. The intercomparison of CH2O measurements is first tested, providing a unique and consistent 3-D-spatially resolved CH2O database in background and convective conditions. While carbon monoxide (CO) is vertically uplifted by deep convection up to 12 km, CH2O is also affected by cloud processing as seen from its ratio relative to CO with altitude. A new observation-based model is established to quantify the SE of CH2O. This model shows that convective entrainment of free tropospheric air cannot be neglected since it contributes to 40% of the convective UT air. For the 4 studied MCS, SE shows a large variability within a 4% to 39% range at a relative standard deviation of 30%, which is consistent with MCS features. A time-dependent photochemical box model is applied to convective UT air. After convection, 60% of CH2O is due to its photochemical production rather than to its direct transport. Model results indicate that CH2O directly injected by convection does not impact ozone and HOx production in the tropical UT of West Africa. NOx and anthropogenic hydrocarbon precursors dominate the secondary production of CH2O, ozone and HOx.

Published
2012

18. Supplementary material to "Impact of chamber wall loss of gaseous organic compounds on secondary organic aerosol formation: explicit modeling of SOA formation from alkane and alkene oxidation"

Author

La, Y. S., primary, Camredon, M., additional, Ziemann, P. J., additional, Valorso, R., additional, Matsunaga, A., additional, Lannuque, V., additional, Lee-Taylor, J., additional, Hodzic, A., additional, Madronich, S., additional, and Aumont, B., additional

Published
2015
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22. Aging of secondary organic aerosol generated from the ozonolysis of α-pinene: effects of ozone, light and temperature

Author

Denjean, C., primary, Formenti, P., additional, Picquet-Varrault, B., additional, Camredon, M., additional, Pangui, E., additional, Zapf, P., additional, Katrib, Y., additional, Giorio, C., additional, Tapparo, A., additional, Temime-Roussel, B., additional, Monod, A., additional, Aumont, B., additional, and Doussin, J. F., additional

Published
2015
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24. The SOA/VOC/NOx system: an explicit model of secondary organic aerosol formation

Author

Camredon, M., Aumont, B., Lee-Taylor, J., Sasha Madronich, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), National Center for Atmospheric Research [Boulder] (NCAR), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and EGU, Publication

Subjects
lcsh:Chemistry, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, 010504 meteorology & atmospheric sciences, lcsh:QD1-999, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, 010501 environmental sciences, 01 natural sciences, lcsh:Physics, lcsh:QC1-999, 0105 earth and related environmental sciences
Abstract

Our current understanding of secondary organic aerosol (SOA) formation is limited by our knowledge of gaseous secondary organics involved in gas/particle partitioning. The objective of this study is to explore (i) the potential for products of multiple oxidation steps contributing to SOA, and (ii) the evolution of the SOA/VOC/NOx system. We developed an explicit model based on the coupling of detailed gas-phase oxidation schemes with a thermodynamic condensation module. Such a model allows prediction of SOA mass and speciation on the basis of first principles. The SOA/VOC/NOx system is studied for the oxidation of 1-octene under atmospherically relevant concentrations. In this study, gaseous oxidation of octene is simulated to lead to SOA formation. Contributors to SOA formation are shown to be formed via multiple oxidation steps of the parent hydrocarbon. The behaviour of the SOA/VOC/NOx system simulated using the explicit model agrees with general tendencies observed during laboratory chamber experiments. This explicit modelling of SOA formation appears as a useful exploratory tool to (i) support interpretations of SOA formation observed in laboratory chamber experiments, (ii) give some insights on SOA formation under atmospherically relevant conditions and (iii) investigate implications for the regional/global lifetimes of the SOA.

Published
2007

25. Supplementary material to "Aging of secondary organic aerosol generated from the ozonolysis of α-pinene: effects of ozone, light and temperature"

Author

Denjean, C., primary, Formenti, P., additional, Picquet-Varrault, B., additional, Camredon, M., additional, Pangui, E., additional, Zapf, P., additional, Katrib, Y., additional, Giorio, C., additional, Tapparo, A., additional, Temime-Roussel, B., additional, Monod, A., additional, Aumont, B., additional, and Doussin, J. F., additional

Published
2014
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26. Aging of secondary organic aerosol generated from the ozonolysis of α-pinene: effects of ozone, light and temperature

Author

Denjean, C., primary, Formenti, P., additional, Picquet-Varrault, B., additional, Camredon, M., additional, Pangui, E., additional, Zapf, P., additional, Katrib, Y., additional, Giorio, C., additional, Tapparo, A., additional, Temime-Roussel, B., additional, Monod, A., additional, Aumont, B., additional, and Doussin, J. F., additional

Published
2014
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29. Study of the unknown HONO daytime source at a European suburban site during the MEGAPOLI summer and winter field campaigns

Author

Michoud, V., primary, Colomb, A., additional, Borbon, A., additional, Miet, K., additional, Beekmann, M., additional, Camredon, M., additional, Aumont, B., additional, Perrier, S., additional, Zapf, P., additional, Siour, G., additional, Ait-Helal, W., additional, Afif, C., additional, Kukui, A., additional, Furger, M., additional, Dupont, J. C., additional, Haeffelin, M., additional, and Doussin, J. F., additional

Published
2014
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30. Study of the unknown HONO daytime source at an European suburban site during the MEGAPOLI summer and winter field campaigns

Author

Michoud, V., primary, Colomb, A., additional, Borbon, A., additional, Miet, K., additional, Beekmann, M., additional, Camredon, M., additional, Aumont, B., additional, Perrier, S., additional, Zapf, P., additional, Siour, G., additional, Ait-Helal, W., additional, Afif, C., additional, Kukui, A., additional, Furger, M., additional, Dupont, J. C., additional, Haeffelin, M., additional, and Doussin, J. F., additional

Published
2013
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31. Supplementary material to "Study of the unknown HONO daytime source at an European suburban site during the MEGAPOLI summer and winter field campaigns"

Author

Michoud, V., primary, Colomb, A., additional, Borbon, A., additional, Miet, K., additional, Beekmann, M., additional, Camredon, M., additional, Aumont, B., additional, Perrier, S., additional, Zapf, P., additional, Siour, G., additional, Ait-Helal, W., additional, Afif, C., additional, Kukui, A., additional, Furger, M., additional, Dupont, J. C., additional, Haeffelin, M., additional, and Doussin, J. F., additional

Published
2013
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34. SOA formation from the photooxidation of α-pinene: systematic exploration of the simulation of chamber data.

Author

McVay, R. C., Zhang, X., Aumont, B., Valorso, R., Camredon, M., La, Y. S., Wennberg, P. O., and Seinfeld, J. H.

Abstract

Chemical mechanisms play an important role in simulating the atmospheric chemistry of volatile organic compound oxidation. Comparison of mechanism simulations with laboratory chamber data tests our level of understanding of the prevailing chemistry as well as the dynamic processes occurring in the chamber itself. α-pinene photooxidation is a well-studied system experimentally, for which detailed chemical mechanisms have been formulated. Here, we present the results of simulating low-NO α-pinene photooxidation experiments conducted in the Caltech chamber with the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) under varying concentrations of seed particles and OH levels. Unexpectedly, experiments conducted at low and high OH levels yield the same SOA growth, whereas GECKO-A predicts greater SOA growth under high OH levels. SOA formation in the chamber is a result of a competition among the rates of gas-phase oxidation to low volatility products, wall deposition of these products, and condensation into the aerosol phase. Various processes, such as photolysis of condensed-phase products, particle-phase dimerization, and peroxy radical autoxidation, are explored to rationalize the observations. In order to explain the observed similar SOA growth under different OH levels, we conclude that vapor wall loss in the Caltech chamber is likely of order 10-5 s-1, consistent with previous experimental measurements in that chamber. We find that GECKO-A tends to overpredict the contribution to SOA of later-generation oxidation products under high OH conditions. The key role of the interplay among oxidation rate, product volatility, and vapor-wall deposition in chamber experiments is illustrated. [ABSTRACT FROM AUTHOR]

Published
2015
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35. Radical budget analysis in a suburban European site during the MEGAPOLI summer field campaign

Author

Michoud, V., primary, Kukui, A., additional, Camredon, M., additional, Colomb, A., additional, Borbon, A., additional, Miet, K., additional, Aumont, B., additional, Beekmann, M., additional, Durand-Jolibois, R., additional, Perrier, S., additional, Zapf, P., additional, Siour, G., additional, Ait-Helal, W., additional, Locoge, N., additional, Sauvage, S., additional, Afif, C., additional, Gros, V., additional, Furger, M., additional, Ancellet, G., additional, and Doussin, J. F., additional

Published
2012
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38. Supplementary material to "Radical budget analysis in a suburban European site during the MEGAPOLI summer field campaign"

Author

Michoud, V., primary, Kukui, A., additional, Camredon, M., additional, Colomb, A., additional, Borbon, A., additional, Miet, K., additional, Aumont, B., additional, Beekmann, M., additional, Durand-Jolibois, R., additional, Perrier, S., additional, Zapf, P., additional, Siour, G., additional, Ait-Helal, W., additional, Locoge, N., additional, Sauvage, S., additional, Gros, V., additional, Afif, C., additional, Furger, M., additional, Ancellet, G., additional, and Doussin, J. F., additional

Published
2012
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39. Transport and chemistry of formaldehyde by mesoscale convective systems in West Africa during AMMA 2006

Author

Borbon, Agnès, primary, Ruiz, M., additional, Bechara, J., additional, Aumont, B., additional, Chong, M., additional, Huntrieser, H., additional, Mari, C., additional, Reeves, C. E., additional, Scialom, Georges, additional, Hamburger, T., additional, Stark, H., additional, Afif, C., additional, Jambert, C., additional, Mills, G., additional, Schlager, H., additional, and Perros, P. E., additional

Published
2012
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48. Impact of chamber wall loss of gaseous organic compounds on secondary organic aerosol formation: explicit modeling of SOA formation from alkane and alkene oxidation.

Author

La, Y. S., Camredon, M., Ziemann, P. J., Valorso, R., Matsunaga, A., Lannuque, V., Lee-Taylor, J., Hodzic, A., Madronich, S., and Aumont, B.

Abstract

Recent studies have shown that low volatility gas-phase species can be lost onto the smog chamber wall surfaces. Although this loss of organic vapors to walls could be substantial during experiments, its effect on secondary organic aerosol (SOA) formation has not been well characterized and quantified yet. Here the potential impact of chamber walls on the loss of gaseous organic species and SOA formation has been explored using the Generator for Explicit Chemistry and Kinetics of the Organics in the Atmosphere (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 series (linear, cyclic and C12-branched alkanes and terminal, internal and 2-methyl alkenes with 7 to 17 carbon atoms) under high NOx conditions. Simulated trends match observed trends within and between homologous series. The loss of organic vapors to the chamber walls is found to affect SOA yields as well as the composition of the gas and the particle phases. Simulated distributions of the species in various phases suggest that nitrates, hydroxynitrates and carbonylesters could substantially be lost onto walls. The extent of this process depends on the rate of gas/wall mass transfer, the vapor pressure of the species and the duration of the experiments. This work suggests that SOA yields inferred from chamber experiments could be underestimated up to 0.35 yield unit due to the loss of organic vapors to chamber walls. [ABSTRACT FROM AUTHOR]

Published
2015
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49. Multiday production of condensing organic aerosol mass in urban and forest outflow.

Author

Lee-Taylor, J., Hodzic, A., Madronich, S., Aumont, B., Camredon, M., and Valorso, R.

Abstract

Secondary organic aerosol (SOA) production in air masses containing either anthropogenic or biogenic (terpene-dominated) emissions is investigated using the explicit gas-phase chemical mechanism generator GECKO-A. Simulations show several-fold increases in SOA mass continuing for several days in the urban outflow, even as the initial air parcel is diluted into the regional atmosphere. The SOA mass increase in the forest outflow is more modest (~50 %) and of shorter duration (1-2 days). The production in the urban outflow stems from continuing oxidation of gas-phase precursors which persist in equilibrium with the particle phase, and can be attributed to multigenerational reaction products of both aromatics and alkanes. In particular we find large contributions from substituted maleic anhydrides and multi-substituted peroxide-bicyclic alkenes. The results show that the predicted production is a robust feature of our model even under changing atmospheric conditions, and contradict the notion that SOA undergoes little mass production beyond a short initial formation period. The results imply that anthropogenic aerosol precursors could influence the chemical and radiative characteristics of the atmosphere over an extremely wide region, and that SOA measurements near precursor sources may routinely underestimate this influence. [ABSTRACT FROM AUTHOR]

Published
2014
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