HR: 11:35h
AN: A41F-06    [PDF]
TI: Comparison of Day- and Nighttime Oxidation of Biogenic and Anthropogenic VOCs Along the New England Coast in Summer During NEAQS 2002
AU: * Warneke, C
EM: cwarneke@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: * Warneke, C
EM: cwarneke@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: de Gouw, J A
EM: jdegouw@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: de Gouw, J A
EM: jdegouw@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: Golden, P D
EM: pgoldan@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Kuster, W C
EM: bkuster@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Williams, E J
EM: ewilliams@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Williams, E J
EM: ewilliams@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: Lerner, B
EM: Brian.Lerner@noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Lerner, B
EM: Brian.Lerner@noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: Brown, S S
EM: sbrown@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Brown, S S
EM: sbrown@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: Stark, H
EM: hstark@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Stark, H
EM: hstark@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: Aldener, M
EM: maldener@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Aldener, M
EM: maldener@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AU: Jakoubek, R
EM: jakoubek@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Roberts, J M
EM: jr@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Marchewka, M
EM: marchewka7@yahoo.com
AF: Department of Chemistry, Western Michigan University, 3425 Wood Hall, Kalamazoo, MI 49008 United States
AU: Fehsenfeld, F C
EM: fcf@al.noaa.gov
AF: NOAA Aeronomy Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Fehsenfeld, F C
EM: fcf@al.noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences (CIRES), 216 UCB, Boulder, CO 80309 United States
AB: Volatile organic compounds (VOCs) and some of their oxidants (O$_{3}$, NO$_{3}$) were measured on board the NOAA research ship Ronald H. Brown along the coast of New England, downwind of New York, Boston and Portsmouth and large forested areas in New Hampshire, Maine, and Massachusetts in July and August 2002. The diurnal variations of isoprene, monoterpenes, and aromatics were mainly dependent on the abundance of the oxidants OH and NO$_{3}$ and on the emissions. Elevated mixing ratios of short lived VOCs were only encountered at the ship, which was about 1-6 hours downwind of the sources, when the concentrations of the oxidants were low. For the biogenic compounds this was generally the case during morning and evening hours, when the lifetime of the biogenics was long due to low OH and NO$_{3}$ concentrations. On the other hand, most anthropogenic VOCs do not react with NO$_{3}$ and therefore their mixing ratios remained elevated during the night. The products of isoprene oxidation, methyl vinyl ketone, methacrolein, and peroxymethacrylic nitric anhydride (MPAN) were on average higher than isoprene itself. Only during the transition periods from day to night, when oxidation rates were at a minimum, could isoprene exceed its products. The loss of the biogenic VOCs was dominated by reactions with NO$_{3}$, whereas the loss of anthropogenics came mostly from reactions with OH. The oxygenated VOCs are the major contributor to the OH loss, except in close vicinity of emission sources. The total loss of biogenic compounds during the night was so effective that after one night of transport they were in most cases completely reacted away, whereas the mixing ratios of the anthropogenic compounds remained high during the night. The pool of reactive hydrocarbons after one night was thus typically dominated by anthropogenic VOCs.
DE: 0365 Troposphere--composition and chemistry
DE: 0368 Troposphere--constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting