Determining the Fractional Solubility of Aerosols in the Mid-Pacific, its Seasonal Variability and Role in Delivering Micronutrients to the Surface Ocean

University Of Hawaii, Honolulu

Investigators

Abstract

ABSTRACT OCE-0082317 Understanding the magnitude and variation of the deposition and partial dissolution of atmospheric dust in the surface ocean is important because it represents a largely unquantified link in the geochemical cycle of reactive trace metals and may contribute significant amounts of biologically active elements. For this reason, the principal investigators plan to collect aerosols over a seasonal cycle from the atmospheric sampling facility at Bellows Air Force Base on Oahu, Hawaii and subject them to a series of dissolution experiments to determine the fractional solubility of Al, Fe and Co in aqueous matrices mimicking rain and surface seawater. Results of the dissolution experiments will be compared to the concentration of the same dissolved trace elements in rain water collected at the same site to establish the validity of using aerosol suspensions as a means of estimating dust solubility. This study will provide a comprehensive assessment of the fractional solubility of biologically important trace elements from atmospheric aerosols during a seasonal cycle and ascertain the factors that control it. In addition, the aerosol project also will elucidate the role that dust deposition of potentially limiting micronutrients to the surface ocean play in promoting biological processes and how past changes in atmospheric dust loadings may have affected surface water biogeochemical fluxes including carbon.