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List of Abstracts 139P-Transformation.31 ID:4600 10:30Development and Application of a Geographical Tagged-Species Source Apportionment Method toCharacterize Transport of Primary PM Components in a Regional Air Quality ModelMehrez Samaali 1 , Véronique Bouchet 2 , Michael Moran 2 , Mourad Sassi 11 Air Quality Modelling Application Section, Canadian Meteorological Centre, Environment Canada, 21212 Air Quality Research Division, Environment Canada, 4905 Dufferin Street, Toronto, ON, M3H 5T4, CanadContact: mehrez.samaali@ec.gc.caAtmospheric transport of particulate matter (PM) and its precursors is a serious issue for human healthproblems as well as air quality management. Regional Eulerian PM air quality models are designed to helpunderstand how PM is formed and transported between regions or countries. However, most PM air qualitymodels do not have built-in source apportionment capabilities to isolate and quantify the contribution ofvarious source categories or regions to the PM burden at a given receptor. The work presented here focuseson the development, evaluation, and application of a geographical, emissions-based source apportionmentmethod within the regional air quality modelling system AURAMS (A Unified Regional Air qualityModelling System).AURAMS was developed by Environment Canada to describe the formation of ozone, particulate matter(PM), and acid deposition in the troposphere. The off-line AURAMS chemical transport model is drivenwith meteorological fields from the Canadian operational weather forecast model GEM and solves chemicaland micro-physical processes related to size-segregated, internally-mixed aerosol particles made up of 9chemical components (sulphate, nitrate, ammonium, elemental carbon, primary organic matter, secondaryorganic matter, crustal material, sea-salt, and particle-bound water) and their interaction with gaseous copollutantsin multiple phases.The tagged-species source apportionment method that was implemented in AURAMS can track primaryorganic matter emissions from selected regions throughout a North American continental domain (Canada,U.S., and northern Mexico). The method has been checked in terms of mass conservation and the hypothesesrelated to primary processes. As a sample application, the relative contributions of Canada and the U.S. toNorth American ambient organic carbon concentrations for a one-month simulation will be discussed. Theseresults will also be compared to results from two brute-force “zero-out“ sensitivity simulations.P-Transformation.32 ID:3559 10:30Particle phase products from the reaction of nopinone with OH radicalsAnke Heinold, Yoshiteru Iinuma, Olaf Böge, Ariane Kahnt, Hartmut HerrmannLeibniz-Institute of Tropospheric ResearchContact: anke.heinold@tropos.deβ-Pinene is one of the most abundant monoterpenes after α-pinene in the atmosphere. The oxidation of thesecompounds leads to semi-volatile compounds that form secondary organic aerosol (SOA). In addition, theseoxidation products can be oxidized further to form a wide range of secondary oxidation products that alsoplay an important role in the formation of SOA. The knowledge about the particle phase products is anessential step towards a better understanding of the atmospheric degradation of the monoterpenes. Wepresent the results from a series of chamber experiments of the known β-pinene oxidation product, nopinone,with OH radicals. The produced particulate products were sampled using a denuder/PTFE filter device. Afterextraction, the filter samples were analysed using HPLC/(-)ESI-TOFMS. The influence of the reactionconditions were investigated by using different OH sources and changing the particle acidity. The followingseed particles were used for the experiments: sodium sulfate (pH ≈ 7), ammonium bisulfate (pH ≈ 0.1) andiCACGP-IGAC 2010 14 July, 2010