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Title: Aerosol trace element solubility and deposition fluxes over the Mediterranean Sea and Black Sea basins
Abstract. Aerosol samples collected during summer 2013 on GEOTRACES cruise GA04 in the Mediterranean and Black seas were analysed for their soluble and total metal and major ion composition. The fractional solubilities (soluble divided by total concentrations) of the lithogenic elements (Al, Ti, Mn, Fe, Co and Th) varied strongly with atmospheric dust loading. Solubilities of these elements in samples that contained high concentrations of mineral dust were noticeably lower than at equivalent dust concentrations over the Atlantic Ocean. This behaviour probably reflects the distinct transport and pollutant regimes of the Mediterranean basin. Elements with more intense anthropogenic sources (P, V, Ni, Cu, Zn, Cd and Pb) had a variety of largely independent sources in the region and generally displayed higher fractional solubilities than the lithogenic elements. Calculated dry-deposition fluxes showed a west-to-east decline in the N/P ratio in deposition over the Mediterranean, a factor that contributes to the P-limited status of the eastern basin. Atmospheric deposition may make a significant contribution to the surface water budgets of Mn and Zn in the western Mediterranean.  more » « less
Award ID(s):
2140395
PAR ID:
10648546
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Copernicus
Date Published:
Journal Name:
Biogeosciences
Volume:
22
Issue:
2
ISSN:
1726-4189
Page Range / eLocation ID:
585 to 600
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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