HR: 1340h
AN: A23A-0914    [Abstracts]
TI: Bromine monoxide from short lived halocarbons: implications for atmospheric composition
AU: * Salawitch, R J
EM: Ross.Salawitch@jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive Mail Stop 183-601, Pasadena, CA 91109 United States
AU: Chance, K
EM: kchance@cfa.harvard.edu
AF: Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 United States
AU: Sioris, C
EM: csioris@cfa.harvard.edu
AF: Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 United States
AU: McLinden, C
EM: chris.mclinden@ec.gc.ca
AF: Meteorlogical Service of Canada, 4905 Dufferin Street, Toronto, ON M3H 5T4 Canada
AB: Measurements from the Global Ozone Monitoring Experiment (GOME) launched on the European Space Agency (ESA) ERS-2 satellite in 1995 revealed abundances of total column bromine monoxide (BrO), throughout the global atmosphere, that are a factor of 3 to 4 larger than had been expected based on simulations that had assumed supply of atmospheric bromine from only long-lived source species (lifetime > ~1 year). The GOME observations revealed that bromocarbons with lifetimes much less than a year, supplied mainly by biogenic processes in the ocean, are exerting a profound influence on atmospheric composition, with a reach much larger and more significant than the previously documented polar enhancements of tropospheric boundary layer BrO. We will describe these early GOME observations as well as more recent observations, from the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) instrument on the ESA ENVISAT satellite, that are being used to infer tropospheric versus stratospheric contributions to excess levels of BrO. We will then describe implications of bromine from short lived halocarbons on our understanding of ozone trends in the lowermost stratosphere, on photochemical processes in the free troposphere, and on the oxidation of dimethyl sulfide in the boundary layer. Finally, we will touch on present uncertainties regarding the height dependence of BrO and future observations that are needed to resolve these uncertainties.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0340 Middle atmosphere: composition and chemistry
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005