Size-resolved chemical composition of Australian dust aerosol during winter

作者：Radhi M; Box M A^*; Box G P; Keywood M D; Cohen D D; Stelcer E; Mitchell R M

来源：Environmental Chemistry, 2011, 8(3): 248-262.

DOI：10.1071/EN10134

• chloride depletion
• entrained salt
• ion beam analysis
• Lake Eyre Basin
• mineral dust aerosol
• radiative forcing

Australia is the dominant source of mineral dust aerosol in the Southern Hemisphere, yet the physical, chemical and optical properties of this aerosol remain poorly understood. Four sets of size-resolved aerosol samples were collected at a site on the edge of the Lake Eyre Basin (LEB), in the south-east dust transport pathway. Back trajectory analysis shows that three samples were sourced from the LEB (one during a rare winter dust storm), and one from coastal regions to the south. All samples were subjected to both ion beam analysis and ion chromatography. A Fe/Al ratio of 0.9 was found, consistent with results from our other campaigns to sites in the LEB, significantly higher than typical Northern Hemisphere values (similar to 0.45-0.6). This confirms the iron-rich character of central Australian soils. Clear evidence of marine advection in the fourth sample was also found, and evidence of chloride depletion by nitric acid in two samples.

• 出版日期2011
• 单位CSIRO