HR: 17:00h
AN: A54C-05    [Abstracts]
TI: Spatial distributions, sources and sinks of methyl iodide, methyl chloride, methyl bromide, carbonyl sulfide, and other trace gases from observations over North America during INTEX-NA
AU: * Blake, N J
EM: nblake@uci.edu
AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Blake, D R
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Baker, A
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Beyersdorf, A
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Doezema, L
A54C-05 AF: Loyola Marymount University, Department of Biochemistry and Chemistry, Los Angeles, CA 90045-2659 United States
AU: Meinardi, S
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Novak, B
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Barletta, B
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Midyett, J
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Kamboures, M
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AU: Fuelberg, H E
A54C-05 AF: Florida State University, Department of Meteorology 362 Love Building, Tallahassee, FL 32306-4520 United States
AU: Vay, S A
A54C-05 AF: NASA Langley Research Center, 100 NASA Road, Hampton, VA 23681 United States
AU: Rowland, F S
A54C-05 AF: University of California, Department of Chemistry 516 Rowland Hall, Irvine, CA 92697-2025 United States
AB: Whole air sampling aboard the NASA DC-8 in summer 2004 as part of the Intercontinental Chemical Transport Experiment (INTEX-NA) provided an excellent opportunity to obtain a picture of the spatial distribution of trace gases over the North American continent. Our nearly 3,000 measurements of a wide range of trace gases are a crucial component in the investigation of the influence of anthropogenic and biogenic sources, fires, photochemical and biogenic sinks, long range transport and convection on the northern hemisphere troposphere. Here we highlight just a few interesting features of the trace gas distributions observed during INTEX-NA, including the large contrasts between the character of marine and continental boundary layer air masses. We also saw surprisingly high methyl iodide levels over the continent, which we attribute to strong marine influence during several INTEX-NA flights. However, we do not rule out a small terrestrial source for methyl iodide. The effect of vegetative draw-down was evident in the vertical distribution of carbonyl sulfide during INTEX-NA. Methyl chloride levels were also diminished over the same regions. Methyl bromide "hot spots" over certain agricultural regions of the US suggest continued use of this gas as a soil fumigant.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0322 Constituent sources and sinks
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005