HR: 0800h
AN: A51A-0021    [Abstracts]
TI: Trace metal concentration in Trade Wind aerosols collected over Barbados and Miami.
AU: * Trapp, J M
EM: jtrapp@rsmas.miami.edu
AF: University of Miami - RSMAS, 4600 Rickenbacker CSWY, Miami, FL 33149, United States
AU: Millero, F J
EM: fmillero@rsmas.miami.edu
AF: University of Miami - RSMAS, 4600 Rickenbacker CSWY, Miami, FL 33149, United States
AU: Prospero, J M
EM: jprospero@rsmas.miami.edu
AF: University of Miami - RSMAS, 4600 Rickenbacker CSWY, Miami, FL 33149, United States
AB: African mineral dust aerosols are transported by trade winds to Barbados and often reach Miami. The trace metals contained in these aerosols play an important role in biogeochemical processes and thus the global carbon cycle. High-volume bulk aerosols were collected in the summer dust season (June-September) of 2003 and 2004 in Miami and Barbados on Whatman-41 filters and microwave digested using a modified version of EPA method 3051. Aliquots of digested samples were tested for trace metal concentrations by ICP-MS. Excellent agreement with gravimetrically determined ashed weights was observed with dust concentrations calculated based on Al crustal abundance. As a major component, aluminum averaged 8.7% content in agreement to 8.1% crustal abundance, and was used to examine other trace metals. Al, Fe, V, Cr, Mn, Cu, Co, Ni, Zn, As, Tl, Ba, Cd, Pb and REE's were examined and deviations from average crustal abundance are discussed in relationship to temporal variation and meteorological conditions. In addition, trace metal pollutants in Miami aerosols were examined relative to the relatively clean samples offered by Barbados.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0330 Geochemical cycles (1030)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting