Publication Date:
2011-08-19
Description:
Observations show that the fractional solubility of Fe (FS-Fe, percentage of dissolved to total Fe) in dust aerosol increases considerably from 0.1 % in regions of high dust mass concentration to 80 % in remote regions where concentrations are low. Here, we combined laboratory geochemical measurements with global aerosol model simulations to test the hypothesis that the increase in FS-Fe is due to physical size sorting during transport. We determined the FS-Fe and fractional solubility of Al (FS-Al) in size-fractionated dust generated from two representative soil samples collected from known Saharan dust source regions using a customized dust re-suspension and collection system. The results show that the FS-Fe is size-dependent and ranges from 0.1–0.3 % in the coarse size fractions (〉1 μm) to ~0.2–0.8 % in the fine size fractions (100 μg m−3) to ~0.2 % at low concentrations (
Print ISSN:
1680-7316
Electronic ISSN:
1680-7324
Topics:
Geosciences