Variability of Pb, Isotopes Pb and Fe in the Tropical and Subtropical Atlantic and Pacific Oceans

在近地表，Pb和Fe表现出与季节性温跃层和季节性输入循环的发展相关的季节性循环，以及与大气输送、海洋涡旋和生物水华相关的短期变化。 此外，人为铅进入温跃层和深海作为一个随时间变化的瞬态示踪剂。 铅同位素比值的时间演变可以提供一个年龄示踪剂的北方源深水质量在深海特别实用的部分南大西洋，氚和CFC尚未渗透。 因此，PI将继续每周使用系泊原位微量元素连续采样器（MITESS，时间序列和深海海水样本）和自动微量元素采样器（ATE，最深10 m的样本）采集样本。 这些采样工作的结果将确定月平均值，并检查百慕大和夏威夷观测到的Pb和Fe变化的原因，以及确定铁脉冲是否是造成北太平洋东部海洋站“P”不明水华的原因。 此外，PI将沿着北大西洋深水（NADW）的流动路径收集样本，以记录人为Pb通过NADW渗透到南大西洋的情况，评估Pb同位素是否可用作年龄相关的来源示踪剂，并确定Fe以溶解、胶体和颗粒形式的分配。

ABSTRACTOCE-0002273 Near the surface, Pb and Fe show a seasonal cycle related to the development of the seasonal thermocline and seasonal input cycles, and short-term variability related to the atmospheric transport, ocean eddies, and biological blooms. In addition, anthropogenic Pb is entering the thermocline and deep ocean as a time-dependent transient tracer. The temporal evolution of Pb isotopes ratios may provide an age tracer of Northern Source deep water masses in the deep sea of particular utility in portions of the deep South Atlantic, where tritium and CFCs have not yet penetrated. For this reason, the PI will continue collecting samples on a weekly basis using the Moored In-Situ Trace Element Serial Sampler (MITESS, time series and deep seawater samples) and the Automated Trace Element sampler (ATE, samples up to 10 m depths). Results from these sampling efforts will establish monthly means and examine the causes of observed variability for Pb and Fe at Bermuda and Hawaii, as well as determine whether iron pulses are responsible for unexplained blooms at the eastern North Pacific Ocean Station "P". In addition, the PI will collect samples along the flow path of the North Atlantic Deep Water (NADW) to document the penetration of anthropogenic Pb into the south Atlantic via the NADW, assess whether Pb isotopes can be used as an age-dependent source tracer and establish the partitioning of Fe into dissolved, colloidal and particulate forms.