HR: 1340h
AN: A13B-1179 [Abstracts]
TI: Evaluation Of Sensitivity Of Mass-independent Oxygen Isotopes In Aerosol Nitrate To Environmental Factors Using A Photochemical Box Model
AU: * Dominguez, G
EM: gdominguez@ucsd.edu
AF: University of California, San Diego, Dept. of Chemistry and Biochemistry, La Jolla, CA
92093-0356, United States
AU: Wilkins, G
EM: gwilkins@berkeley.edu
AF: University of California, Berkeley, Department of Physics
Berkeley, CA 94720-7300, Berkeley, CA 94720, United States
AU: Jackson, T
EM: tjackson@ucsd.edu
AF: University of California, San Diego, Dept. of Chemistry and Biochemistry, La Jolla, CA
92093-0356, United States
AU: Brothers, L
EM: lbrother@ucsd.edu
AF: University of California, San Diego, Dept. of Chemistry and Biochemistry, La Jolla, CA
92093-0356, United States
AU: McCabe, J
EM: jmccabe@ucsd.edu
AF: University of California, San Diego, Dept. of Chemistry and Biochemistry, La Jolla, CA
92093-0356, United States
AU: Thiemens, M H
EM: mthiemens@ad.ucsd.edu
AF: University of California, San Diego, Dept. of Chemistry and Biochemistry, La Jolla, CA
92093-0356, United States
AB:
An existing photochemical box model for use in polluted marine boundary layers was modified to allow for the
explicit tracking of the mass-independent isotopic composition of oxygen in aerosol nitrate as well as other
atmospheric species such as OH and H2O2. This modified model was then used to study the sensitivity
of the mass-independent isotopic composition of atmospheric nitrate(HNO3) to variables such as relative
humidity, temperature ozone and NOx concentrations. Here we present the results of these studies and compare
model predictions of the mass-independent oxygen isotopic composition of aerosol nitrate to measurements
taken in fine (<1micron) and coarse (>1 micron) aerosol samples taken in a variety of locations, from coastal
urban environments, the tropics (Ecuador), inland California (Riverside), and Antarctica. Regarding Antarctica,
we comment on the isotopic composition of OH there and the ramifications of these findings for the isotopic
composition of other oxygen bearing compounds in the Antarctic atmosphere.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0317 Chemical kinetic and photochemical properties
DE: 0330 Geochemical cycles (1030)
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting