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

近地表Pb和Fe表现出与季节性温跃层发育和季节性输入周期有关的季节性循环，与大气输送、海洋涡旋和生物华等有关的短期变率。此外，人为的铅正以一种随时间变化的瞬态示踪剂进入温跃层和深海。Pb同位素比值的时间演化可能为深海中北方源深水团提供年龄示踪剂，在氚和氟氯化碳尚未渗透的南大西洋深处部分地区特别有用。因此，PI将继续每周使用系泊原位微量元素串行采样器（MITESS，时间序列和深海样本）和自动微量元素采样器（ATE，深度达10米的样本）收集样本。这些取样工作的结果将建立每月平均值，并检查在百慕大和夏威夷观测到的铅和铁变化的原因，以及确定铁脉冲是否导致北太平洋东部“P”站不明原因的水华。此外，该项目将沿着北大西洋深水（NADW）的流动路径收集样本，以记录人为铅通过NADW进入南大西洋的情况，评估铅同位素是否可以用作年龄依赖的来源示踪剂，并建立铁在溶解、胶体和颗粒形式中的分配。

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.