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

了解海洋表层大气尘埃沉积和部分溶解的程度和变化是很重要的，因为它代表了活性痕量金属地球化学循环中一个很大程度上无法量化的环节，并可能提供大量的生物活性元素。 出于这个原因，主要研究人员计划从夏威夷奥陶洛斯空军基地的大气采样设施收集季节性周期的气溶胶，并对它们进行一系列溶解实验，以确定Al，Fe和Co在模拟雨水和地表海水的含水基质中的溶解度。 将溶解实验的结果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计粉尘溶解度的方法的有效性。 这项研究将全面评估季节性周期中大气气溶胶中具有生物重要性的微量元素的溶解度，并确定控制它的因素。气溶胶项目还将阐明可能限制微量营养素的尘埃沉积到海洋表面在促进生物过程中所起的作用，以及过去大气尘埃负荷的变化可能对生物过程产生的影响包括碳在内的地表水地球化学通量。

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.