HR: 0800h
AN: B51C-0603    [Abstracts]
TI: DMS Sulphate and MSA as tracers of marine biogenic productivity in an Arctic snowpack
AU: * Wasiuta, V
EM: vwasiuta@utas.edu.au
AF: Insitute of Antarctic and Southern Ocean Studies, University of Tasmania Private Bag 77, Hobart, TAS 7001, Austria
AU: Norman, A
AF: Department of Physics and Astronomy, University of Calgary 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
AU: Marshall, S
AF: Department of Geography, University of Calgary 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
AB: Sources, seasonal patterns, and spatial variations of snowpack sulphate of the Prince of Wales Icefield, Ellesmere Island were assessed using δ³⁴S values along with major ion and MSA concentrations. Snowpack sulphate concentrations and δ³⁴S values diminished with elevation and inland distance suggesting that the proximal North Water Polynya was the major sulphate source with additional sources affecting specific regions. Snowpack δ³⁴S values in depth profile reflected seasonal cycles of marine biogenic, anthropogenic, and sea-salt aerosols with appreciable contributions of marine biogenic sulphate to virtually every depth horizon. A proximal April/May marine biogenic source was indicated, with DMS oxidation occurring near the marine boundary layer, and the possibility of additional oxidation at higher atmospheric levels. Depositional patterns of DMS sulphate and MSA indicate they were oxidized from DMS at different elevations in the atmosphere and that their deposition routes differed.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0488 Sulfur cycling
DE: 0776 Glaciology (1621, 1827, 1863)
DE: 1041 Stable isotope geochemistry (0454, 4870)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting