HR: 15:25h
AN: A53G-06    [Abstracts]
TI: Measuring 35S of Aerosol Sulfate: Techniques and First Results
AU: * Brothers, L A
EM: Lbrother@ucsd.edu
AF: Department of Chemistry and Biochemistry University of California, San Diego, 9500 Gilman Drive MC 0356, La Jolla, Ca 92037, United States
AU: Dominguez, G
EM: gdominguez@ucsd.edu
AF: Department of Chemistry and Biochemistry University of California, San Diego, 9500 Gilman Drive MC 0356, La Jolla, Ca 92037, United States
AU: Bluen, B
EM: bbluen@ucsd.edu
AF: Department of Chemistry and Biochemistry University of California, San Diego, 9500 Gilman Drive MC 0356, La Jolla, Ca 92037, United States
AU: Corbin, A
EM: acorbin@ucsd.edu
AF: Department of Chemistry and Biochemistry University of California, San Diego, 9500 Gilman Drive MC 0356, La Jolla, Ca 92037, United States
AU: Abramian, A
EM: aabramia@ucsd.edu
AF: Department of Chemistry and Biochemistry University of California, San Diego, 9500 Gilman Drive MC 0356, La Jolla, Ca 92037, United States
AU: Thiemens, M H
EM: mthiemens@ucsd.edu
AF: Department of Chemistry and Biochemistry University of California, San Diego, 9500 Gilman Drive MC 0356, La Jolla, Ca 92037, United States
AB: On a global and regional level, the cycling of sulfur in the environment has consequences for air quality, human health, and may contribute to global climate change. Due to its multiple oxidation states, the sulfur cycle is very complex and poorly understood. Stable isotopes are currently used to understand reaction pathways as well as sources and sinks of sulfurous compounds in the environment. Sulfur also has one short lived (τ_1/2 ~87 d) radioactive isotope (³⁵S) which is continuously made in the atmosphere by the cosmic ray spallation of argon, is then quickly oxidized to ³⁵SO₂ and enters the atmospheric sulfur cycle. The short-lived radioactive nature of this isotope of sulfur provides us with potentially powerful tracer for understanding the time scales at which sulfur is oxidized, deposited, and transported in the atmosphere and the deposition of atmospheric sulfate into rivers and water catchments. However, despite its potential, the use of ³⁵S as a tracer of aerosol chemistry has not been fully exploited, Here we present details of instrumental set up for measuring ³⁵S in aerosol sulfate and some preliminary results of measurements of ³⁵S abundances in aerosols from Riverside (inland) and La Jolla (coastal) CA and discuss the sensitivity and limitations of the measurements in providing insights into day/night aerosol chemistry (Riverside) as well as the uptake of SO₂ pollution in coastal environments by sea-salt aerosols. Also, we present preliminary results from measurement of sulfate in river water in Ecuador before and after precipitation events.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
DE: 0454 Isotopic composition and chemistry (1041, 4870)
DE: 1040 Radiogenic isotope geochemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting