Emissions and photochemistry of oxygenated VOCs in urban plumes in the Northeastern United States

Abstract

Abstract. Photochemical processes inside urban plumes in the Northeast of the United States have been studied using a highly detailed chemical model, based upon the Master Chemical Mechanism (MCM). The model results have been compared to measurements of oxygenated VOCs (acetone, methyl ethyl ketone, acetaldehyde, acetic acid and methanol) obtained during several flights of the NOAA WP-3D aircraft, which sampled plumes from the New York City area during the ICARTT campaign in 2004. The agreement between the model and the measurements was within 40-60 % for all species, except acetic acid.The model results have been used to study the formation and photochemical evolution of acetone, methyl ethyl ketone and acetaldehyde. Under the conditions encountered during the ICARTT campaign, acetone is produced from the oxidation of propane (24-28 %) and i-propanol (<15 %) and from a number of products of i-pentane oxidation. Methyl ethyl ketone (MEK) is mostly produced from the oxidation of n-butane (20-30 %) and 3-methylpentane (<40 %). Acetaldehyde is formed from several precursors, mostly small alkenes, >C5 alkanes, propanal and MEK. Ethane and ethanol oxidation account, respectively, for 6-23 % and 5-25 % of acetaldehyde photochemical formation. The results highlight the importance of alkanes for the photochemical production of ketones and the role of hydroperoxides in sustaining their formation far from the emission sources.

Source characterization of volatile organic compounds in the Colorado Northern Front Range Metropolitan Area during spring and summer 2015

“…Furthermore, Sommariva et al . [] modeled the major photochemical production pathways for OVOCs, including MEK, in New England using VOC data from the 2002 New England Air Quality Study [ De Gouw et al ., ; Goldan et al ., ] and found n‐butane to be the dominant source of MEK (20–30%). The MEK yield from n‐butane oxidation is on the order of 80% [ Singh et al ., ].…”

“…Sommariva et al . [] found that acetone and acetaldehyde are predominately formed from OH oxidation of propane and ethane in urban airsheds in New England. Considering the elevated mixing ratios of ethane and propane in the NFRMA versus values reported by [ Baker et al ., ] for those New England urban areas, this conclusion is likely also true for the NFRMA.…”

Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, boreal, temperate and marine environments

“…MEK not only enters the atmosphere via direct emissions but also results from the atmospheric photooxidation of VOCs such as n-butane, 2-butanol, 3-methyl pentane and 2-methyl-1-butene (de Gouw et al, 2003;Jenkin et al, 1997;Neier and Strehlke, 2002;Sommariva et al, 2011). Although butane in the atmosphere comes predominantly from anthropogenic sources (Kesselmeier and Staudt, 1999), some studies have reported emission of n-butane from vegetation (Donoso et al, 1996;Greenberg and Zimmerman, 1984;Hellén et al, 2006;König et al, 1995;Zimmerman et al, 1988).…”

“…It is also emitted directly by several anthropogenic sources, including anthropogenic biomass burning (Andreae and Merlet, 2001), solvent evaporation (Kim et al, 2015;Legreid et al, 2007) and vehicle exhaust (Bon et al, 2011;Brito et al, 2015;Liu et al, 2015;Verschueren, 1983). In addition, MEK can be formed via the atmospheric oxidation of other compounds (de Gouw et al, 2003;Jenkin et al, 1997;Neier and Strehlke, 2002;Sommariva et al, 2011).…”

Selected carbonyl compounds in the air of Silesia region

“…Their presence was observed in gases emitted to atmosphere from traffic and industrial sources, including combustion of biomass and solid fuels [2]. Mentioned compounds can be created in course of photooxidation of hydrocabons with help of radicals HO2• and OH• and are part of photochemical smog [3]. Aldehydes play important role in tropospheric chemistry, since they are intermediate products of oxidation processes of hydrocarbons and subsequently generate photochemical products such as carbon monoxide and radical species that contribute to the production of ozone and peroxyacylnitrate in the troposphere.…”