Comparison of Organic Compound Compositions in the Emissions Inventory and Ambient Data for the Lower Fraser Valley

Weimin Jiang (corresponding author) is a research associate at the Institute for Chemical Process and Environmental Technology, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6; phone: (613) 998-3992; e-mail: weimin.jiang@nrc.ca. Don Singleton and Mark Hedley are research officers at the Institute for Chemical Process and Environmental Technology, National Research Council, Canada. Non-methane organic compound (NMOC) composition in an episode-specific emissions inventory is systematically compared with the average summer ambient NMOC composition in the Lower Fraser Valley (LFV) of British Columbia, Canada. The comparison is made on the basis of NMOC classes, carbon numbers of species and classes, and individual chemical species. The composition of species present in the inventory but not measured in the atmosphere is also presented. It is found that the ambient and emissions inventory compositions are in reasonable agreement, with a few exceptions. Because of the similarity in the compositions, the emissions profile in the LFV can be used to approximate the ambient NMOC profile in photochemical modeling of the region. A similar validation procedure would be required in other regions.Discrepancies exist between the emissions inventory and the ambient data for the biogenic compounds isoprene.