Complete Isotopic Analysis of Aerosol Sulfate and Nitrate in Long-Term Samplings from the Tropical Atlantic

University Of California-San Diego, La Jolla CA

Investigators

Abstract

This project investigates the impacts of anthropogenic activities on tropospheric sulfur and nitrogen cycling in the atmosphere. Existing daily aerosol samples acquired by University of Miami (UM) during a several decade long program will be used to study the mass-independent (oxygen, nitrogen and sulfur) isotope effects in sulfates and nitrates occurring in these samples. Specifically, the Mass Independent Fractionation (MIF) of 17O in sulfate and nitrate components of selected aerosol samples, as well as more traditional sulfur and nitrogen isotope analyses will be used to characterize atmospheric oxidative processes with a view to identifying unique reaction pathways occurring in the ambient environment downwind of anthropogenic and natural sources of sulfate and nitrate precursors. Results from this study will further understanding of aerosol formation and atmospheric transport, particularly with respect to elucidating long term changes in aerosol source signatures and production pathways and the potential of these to impact climate. Support is included for a postdoctoral researcher and one graduate student to gain research experience under the mentorship of the principal investigator.