Budget of organic carbon in a polluted atmosphere: Results from the New England Air Quality Study in 2002 Export

@article{citeulike:327210, abstract = {An extensive set of volatile organic compounds (VOCs) and particulate organic matter (POM) was measured in polluted air during the New England Air Quality Study in 2002. Using VOC ratios, the photochemical age of the sampled air masses was estimated. This approach was validated (1) by comparing the observed rates at which VOCs were removed from the atmosphere with the rates expected from OH oxidation, (2) by comparing the VOC emission ratios inferred from the data with the average composition of urban air, and (3) by the ability to describe the increase of an alkyl nitrate with time in terms of the chemical kinetics. A large part of the variability observed for oxygenated VOCs (OVOCs) and POM could be explained by a description that includes the removal of the primary anthropogenic emissions, the formation and removal of secondary anthropogenic species, and a biogenic contribution parameterized by the emissions of isoprene. The OVOC sources determined from the data are compared with the available literature, and a satisfactory agreement is obtained. The observed sub-\&\#956;m POM was highly correlated with secondary anthropogenic gas-phase species, strongly suggesting that the POM was from secondary anthropogenic sources. The results are used to describe the speciation and total mass of gas- and particle-phase organic carbon as a function of the photochemical age of an urban air mass. Shortly after emission the organic carbon mass is dominated by primary VOCs, while after two days the dominant contribution is from OVOCs and sub-\&\#956;m POM. The total measured organic carbon mass decreased by about 40\% over the course of two days. The increase in sub-\&\#956;m POM could not be explained by the removal of aromatic precursors alone, suggesting that other species must have contributed and/or that the mechanism for POM formation is more efficient than previously assumed.}, author = {de Gouw, J. A. and Middlebrook, A. M. and Warneke, C. and Goldan, P. D. and Kuster, W. C. and Roberts, J. M. and Fehsenfeld, F. C. and Worsnop, D. R. and Canagaratna, M. R. and Pszenny, A. A. P. and Keene, W. C. and Marchewka, M. and Bertman, S. B. and Bates, T. S.}, citeulike-article-id = {327210}, citeulike-linkout-0 = {http://www.agu.org/pubs/crossref/2005/2004JD005623.shtml}, citeulike-linkout-1 = {http://dx.doi.org/10.1029/2004JD005623}, day = {30}, doi = {10.1029/2004JD005623}, journal = {Journal of Geophysical Research}, keywords = {aerosol, carbon, organic, speciation, tropospheric, us}, month = {August}, pages = {D16305+}, posted-at = {2005-09-20 23:48:17}, priority = {2}, title = {Budget of organic carbon in a polluted atmosphere: Results from the New England Air Quality Study in 2002}, url = {http://dx.doi.org/10.1029/2004JD005623}, volume = {110}, year = {2005} }

TY - JOUR ID - citeulike:327210 L3 - citeulike-article-id:327210 N2 - An extensive set of volatile organic compounds (VOCs) and particulate organic matter (POM) was measured in polluted air during the New England Air Quality Study in 2002. Using VOC ratios, the photochemical age of the sampled air masses was estimated. This approach was validated (1) by comparing the observed rates at which VOCs were removed from the atmosphere with the rates expected from OH oxidation, (2) by comparing the VOC emission ratios inferred from the data with the average composition of urban air, and (3) by the ability to describe the increase of an alkyl nitrate with time in terms of the chemical kinetics. A large part of the variability observed for oxygenated VOCs (OVOCs) and POM could be explained by a description that includes the removal of the primary anthropogenic emissions, the formation and removal of secondary anthropogenic species, and a biogenic contribution parameterized by the emissions of isoprene. The OVOC sources determined from the data are compared with the available literature, and a satisfactory agreement is obtained. The observed sub-μm POM was highly correlated with secondary anthropogenic gas-phase species, strongly suggesting that the POM was from secondary anthropogenic sources. The results are used to describe the speciation and total mass of gas- and particle-phase organic carbon as a function of the photochemical age of an urban air mass. Shortly after emission the organic carbon mass is dominated by primary VOCs, while after two days the dominant contribution is from OVOCs and sub-μm POM. The total measured organic carbon mass decreased by about 40% over the course of two days. The increase in sub-μm POM could not be explained by the removal of aromatic precursors alone, suggesting that other species must have contributed and/or that the mechanism for POM formation is more efficient than previously assumed. JF - Journal of Geophysical Research TI - Budget of organic carbon in a polluted atmosphere: Results from the New England Air Quality Study in 2002 VL - 110 SP - D16305 KW - aerosol KW - carbon KW - organic KW - speciation KW - tropospheric KW - us AU - de Gouw, JA AU - Middlebrook, AM AU - Warneke, C AU - Goldan, PD AU - Kuster, WC AU - Roberts, JM AU - Fehsenfeld, FC AU - Worsnop, DR AU - Canagaratna, MR AU - Pszenny, AAP AU - Keene, WC AU - Marchewka, M AU - Bertman, SB AU - Bates, TS PY - 2005/08/30/ UR - http://dx.doi.org/10.1029/2004JD005623 ER -