Abstract
Copper speciation was determined in 68 rainwater samples collected in Wilmington, NC, from August 25, 2000, to September 24, 2002. Volume-weighted average concentrations of Cu(total), dissolved Cu(II), and dissolved Cu(I) were 5.3, 3.2, and 1.4 nM, respectively, with a significantly higher ratio of Cu(II)/Cu(I) in summer relative to winter events. The concentrations of all Cu species were higher in storms of continental origin relative to marine-dominated events, suggesting anthropogenic and/or terrestrial sources are important contributors of Cu in precipitation. Concentrations of strong Cu-complexing ligands were consistently lower than dissolved Cu concentrations, indicating a significant portion, but not all, of the dissolved Cu in rainwater is strongly complexed. A portion of these ligands, in addition to the sulfite and chloride in precipitation, may be Cu(I)-complexing ligands, which may explain the resistance of Cu(I) against oxidation in rainwater. Using our rainwater concentration data along with other published rainwater Cu concentrations and an estimate for total global annual rain, the total global flux of Cu removed from the atmosphere via wet deposition is 150 x 106 kg yr(-1). This represents complete removal of the estimated Cu input into the troposphere and indicates essentially all Cu released into the global atmosphere is removed by rain.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.