Trace metal fractional solubility in size-segregated aerosols from the tropical eastern Atlantic Ocean

Alex Baker, Mingpei Li, Rosie J. Chance

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)
13 Downloads (Pure)

Abstract

Soluble and total trace metals were measured in four size fractionated aerosol samples collected over the tropical eastern Atlantic Ocean. In samples that were dominated by Saharan dust, the size distributions of total iron, aluminum, titanium, manganese, cobalt, and thorium were very similar to one another and to the size distributions of soluble manganese, cobalt, and thorium. Finer particle sizes (< ~3 μm) showed enhanced soluble concentrations of iron, aluminum, and titanium, possibly as a result of interactions with acidic sulfate aerosol during atmospheric transport. The difference in fine particle solubility between these two groups of elements might be related to the hyperbolic increase in the fractional solubility of iron, and a number of other elements, during the atmospheric transport of Saharan dust, which is not observed for manganese and its associated elements. In comparison to elements whose solubility varies during atmospheric transport, the stability of thorium fractional solubility should reduce uncertainties in the use of dissolved concentrations of this element in seawater as a proxy for dust deposition, although this topic requires further work.
Original languageEnglish
Article numbere2019GB006510
Number of pages9
JournalGlobal Biogeochemical Cycles
Volume34
Issue number6
Early online date3 Jun 2020
DOIs
Publication statusPublished - Jun 2020

Keywords

  • Dust aerosol
  • GEOTRACES
  • Solubility
  • Trace elements

Cite this