HR: 0830h
AN: A51D-0713    [PDF]
TI: Non-Methane Hydrocarbon Measurements Aboard the NOAA Research Vessel Ronald H. Brown during the 2002 New England Air Quality Study (NEAQS 2002)
AU: * Goldan, P D
EM: pgoldan@al.noaa.gov
AF: Aeronomy Lab. NOAA U.S. Dept. of Commerce, 325 Broadway, Boulder, CO 80305
AU: Kuster, W C
AF: Aeronomy Lab. NOAA U.S. Dept. of Commerce, 325 Broadway, Boulder, CO 80305
AU: Williams, E
AF: Aeronomy Lab. NOAA U.S. Dept. of Commerce, 325 Broadway, Boulder, CO 80305
AU: Williams, E
AF: Cooperative Institute for Reseach in Environmental Sciences (CIRES), University of Colorado, Boulder, CO 80309
AU: Fehsenfeld, F C
AF: Aeronomy Lab. NOAA U.S. Dept. of Commerce, 325 Broadway, Boulder, CO 80305
AU: Fehsenfeld, F C
AF: Cooperative Institute for Reseach in Environmental Sciences (CIRES), University of Colorado, Boulder, CO 80309
AB: During the NEAQS 2002 study, in-situ NMHC measurements were made aboard the NOAA research vessel Ronald H. Brown by a two channel automated gas chromatograph using both flame ionization and mass-spectrometric detection techniques. Five minute average samples were cryogenically trapped each 1/2 hour and analyzed immediately for C2 through C10 alkanes, C2 through C5 alkenes, C6 through C9 aromatics, C2 through C8 aldehydes and ketones, C1 through C5 alcohols and a variety of compounds of biogenic origin including 6 monoterpenes, isoprene and its primary oxidation products methacrolein and methylvinyl ketone. The relative contributions of these classes of compounds to OH photochemistry has been determined for air masses ranging from those showing significant anthropogenic influence to clean marine air. For the most anthropogenically influenced air masses, alkenes were observed to play a dominant role whereas oxy-hydrocarbons, principally acetaldehyde, were observed to dominate under clean marine conditions. Both the NMHC measurements and back trajectory analyses indicated periods of significant influx into the New England coastal region of urban air masses showing elevated ozone levels from the Boston/Providence urban corridor. About as frequently, less photochemically mature air masses, depleted in ozone but laden with light reactive alkenes, were observed coming from the Portsmouth NH/Kittery ME coastal urban complex. Even in the presence of these anthropogenic plumes, biogenic hydrocarbons appear to dominate OH photochemistry in the New England region much of the time. Data demonstrating all of these conclusions will be shown.
DE: 0315 Biosphere/atmosphere interactions
DE: 0322 Constituent sources and sinks
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