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

0082317了解大气尘埃在表层海洋中沉积和部分溶解的大小和变化是很重要的，因为它在很大程度上代表着活性痕量金属的地球化学循环中的一个未量化的环节，并可能贡献大量的生物活性元素。为此，首席研究人员计划在一个季节性周期内从夏威夷瓦胡岛贝洛斯空军基地的大气采样设施收集气溶胶，并对其进行一系列溶解实验，以确定铝、铁和钴在模拟雨水和表层海水的水中的部分溶解度。溶解实验的结果将与在同一地点收集的雨水中相同溶解微量元素的浓度进行比较，以确定使用气溶胶悬浮液作为估算粉尘溶解度的手段的有效性。这项研究将全面评估季节循环期间大气气溶胶中具有生物重要性的微量元素的部分溶解度，并确定控制它的因素。此外，气溶胶项目还将阐明可能限制微营养素进入表层海洋的尘埃沉积在促进生物过程中的作用，以及过去大气尘埃载量的变化可能如何影响包括碳在内的地表水生物地球化学通量。

ABSTRACTOCE-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.