HR: 0830h
AN: A31D-0070    [PDF]
TI: One Year of Continuous In-Situ NMHC Measurements in Rural Ontario, Canada
AU: * Brickell, P C
EM: Peter.Brickell@ec.gc.ca
AF: Air Quality Research Branch, Meteorological Service of Canada, 4905 Dufferin Street, Toronto, On M3H 5T4 Canada
AU: Bottenheim, J W
EM: Jan.Bottenheim@ec.gc.ca
AF: Air Quality Research Branch, Meteorological Service of Canada, 4905 Dufferin Street, Toronto, On M3H 5T4 Canada
AU: Froude, F
EM: Frank.Froude@ec.gc.ca
AF: Centre for Atmospheric Research Experiments, Meteorological Service of Canada, R.R., Egbert, On L0L 1N0 Canada
AU: Jiang, Z
EM: Zhimei.Jiang@ec.gc.ca
AF: Air Quality Research Branch, Meteorological Service of Canada, 4905 Dufferin Street, Toronto, On M3H 5T4 Canada
AB: Speciated in-situ measurements of 37 Nonmethane Hydrocarbon compounds (C2 to C8) are routinely made at the Centre for Atmospheric Research Experiments (CARE) in Egbert (Southern Ontario, Canada). CARE is home to one of Environment Canada's six regional enhanced air quality monitoring sites and is located in a rural setting, approximately 70 km north of the city of Toronto. The site is impacted by both urban/industrial air masses from the South and relatively unpolluted continental air masses from the Northwest. NMHC measurements have been made at this site since March, 2001 at a frequency of 6-8 samples per day. We report here the data from April, 2002 -March, 2003. The fully automated measurements are made by means of a liquid nitrogen-cooled glass bead pre-concentration trap and multi-column capillary Gas Chromatography/Flame Ionization Detection. Detection limits range from 5 to 16 parts per trillion by volume with an air sampling volume of 930 mL. Routinely reported are mixing ratios of the C2 and C3 alkanes, alkenes, and alkynes, C4 and C5 alkanes and alkenes including isoprene (2-methyl-1,3-butadiene), C6 alkanes, benzene, toluene, and xylene isomers. We discuss diurnal and seasonal trends in the data. Back trajectory calculations are used to indicate source profiles and to estimate the impact of Arctic air masses on this site. The amount of photochemical processing from various source directions is estimated using hydrocarbon ratio data. Anomalous C7 and C8 aromatic data are investigated to assess the possible impact of local sources on the site.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0345 Pollution--urban and regional (0305)
DE: 0365 Troposphere--composition and chemistry
DE: 0368 Troposphere--constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting