Collaborative Research: Defining the Atmospheric Deposition of Trace Elements Into The Arctic Ocean-Ice Ecosystem During The Year-Long MOSAiC Ice Drift.

该项目将在为期一年的考察中使用铍7 （7- be）方法，作为国际多学科北极气候研究漂流观测站（MOSAiC）考察的一部分，以评估气溶胶沉积的季节性变化。这是现代首次有机会对微量元素（TEs）进入北冰洋/冰生态系统的年沉积通量进行如此全面的研究。7-Be和气溶胶TE测量相结合已被证明是估算偏远海洋地区TE的大气输入的有效工具，因为附近没有陆基收集点。在这项工作中产生的数据将可用于使气溶胶沉积和te的大气输入模式的地面真实性。大气沉积是人类活动产生的微量元素，特别是汞（Hg）进入北冰洋的主要途径，最近的文献表明，铁（Fe）等生物必需微量元素的大气沉积可能在控制北极生物生产力方面发挥重要作用。气溶胶的大气输送和沉积是向北极输送天然微量元素和污染物微量元素的重要机制。现有数据表明，汞、铅和硒等污染物元素的大气沉降可能是这些元素进入北极的主要来源，可能的来源是人为的——欧洲、俄罗斯和亚洲与化石燃料燃烧有关的工业或发电厂排放。大气输入的生物必需微量元素（如Mn、Fe、Co、Ni、Cu、Zn）在控制海洋生物地球化学过程中起着关键作用，最近的研究表明，这可能在北极也是如此。这些投入对生态系统甚至人类健康都有重大影响。对这种投入的评估是困难的，因为对偏远海洋地区沉积速率的测量是稀缺的，在北极尤其令人生畏，因为恶劣的条件和有限的研究平台使得难以在常规基础上获得有质量控制的降水和气溶胶化学测量。这项研究将提供气溶胶TEs（总和可溶性）的年大气沉积通量的估计，包括那些具有生物地球化学重要性的以及污染物种类。并对不同集水区（冰、水、雪、融池）中微量元素沉积分配的季节演变进行了评价。这项工作将包括测量7-Be库存、7-Be气溶胶活动和TEs气溶胶浓度。实地工作将在为期一年的马赛克探险队穿越北冰洋中部的冰漂移期间进行。这个项目将是MOSAiC考察的一个组成部分，MOSAiC是一项国际倡议，由快速发展的北极气候系统驱动，海冰变薄，海洋和大气温度变暖，强烈的气候反馈，以及对社会的巨大影响。MOSAiC得到了广泛的国际支持，并得到了国际和美国机构的认可，作为一个迫切需要的项目，它可以为支持耦合模型开发所需的北极中部系统变化提供基础信息。提供相关te向北冰洋的大气输入的估算能力将对化学海洋学领域做出广泛贡献，包括了解对该地区的人为影响以及te的大气输入在北冰洋生态中的作用。领导机构是全国领先的少数民族服务大学之一，首席研究员为参与其研究活动的学生开展了指导计划。该团队将录制简短的讲座和视频日志，以便在他未来的课程迭代中使用，以介绍重要的海洋学概念，并为他的学生提供在海洋船上生活的第一手资料。其他科学家将被要求接受采访，以增加视角的广度，而拓展活动将强调基础科学研究在提高我们对自然现象和地球对人为压力源的反应的理解方面的作用。

This project will use a Beryllium 7 (7-Be) method in a year-long expedition as part of the international Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition to assess the seasonal variability of aerosol deposition. This is the first modern opportunity for such a comprehensive study of the yearly depositional flux of trace elements (TEs) into the Arctic ocean/ice ecosystem. The combination of 7-Be and aerosol TE measurements has been shown to be an effective tool for estimating the atmospheric input of TEs in remote ocean regions where nearby land-based collection sites do not exist. The data generated in this work will be available to allow ground-truthing of models of aerosol deposition and atmospheric input of TEs. Atmospheric deposition is the dominant pathway by which anthropogenically-derived trace elements, especially mercury (Hg), enter the Arctic Ocean, and recent literature suggests that atmospheric deposition of biologically-essential trace elements such as iron (Fe) could play a major role in controlling biological productivity in the Arctic.Atmospheric transport and deposition of aerosols is an important delivery mechanism of natural and contaminant trace elements (TEs) to the Arctic. Existing data show that atmospheric deposition of contaminant elements like Hg, Pb, and Se may be a major input of these elements to the Arctic, with likely sources being anthropogenic - industrial or power plant emissions associated with fossil fuel combustion in Europe, Russia, and Asia. The atmospheric input of biologically-essential trace elements (e.g. Mn, Fe, Co, Ni, Cu, Zn) plays a key role in controlling biogeochemical processes in the ocean, and recent work suggests this might be true in the Arctic as well. These inputs have strong implications for the ecosystem, and even human health. Assessment of this input is difficult because measurements of deposition rates in remote ocean regions are scarce, and are particularly daunting to take in the Arctic because harsh conditions and limited research platforms make it difficult to obtain quality-controlled precipitation and aerosol chemistry measurements on a routine basis. This research will provide estimates of the yearly atmospheric deposition flux of aerosol TEs (total and soluble), including those of biogeochemical importance as well as pollutant species. The seasonal evolution of partitioning of trace element deposition among the various catchments (ice, water, snow, melt ponds) will also be assessed. The work will involve measurements of 7-Be inventories, 7-Be aerosol activities, and aerosol concentrations of TEs. Field work will be during a year-long ice drift of the MOSAiC expedition through the central Arctic Ocean.This project will be a component of the MOSAiC expedition, an international initiative motivated by the rapidly evolving Arctic climate system, with thinning sea ice, warming ocean and atmosphere temperatures, strong climate feedbacks, and dramatic implications for society. MOSAiC has broad international support and has been endorsed by international and US institutions as a project that is critically needed to provide foundational information on the changing central Arctic system required to support coupled model development. The ability to provide estimates of the atmospheric input of relevant TEs to the Arctic Ocean will contribute widely to the field of chemical oceanography, including understanding anthropogenic impacts on the region and the role atmospheric input of TEs plays in Arctic Ocean ecology. The lead institution is one of the country's leading minority serving universities, and the lead researcher has undertaken a mentoring program for students involved in its research activities. The team will record short lectures and video logs that can be used in future iterations of his courses to introduce important oceanographic concepts and give his students a first-hand account of life aboard an oceanographic vessel. Other scientists will be asked to grant interviews to add to the breadth of perspectives, and the outreach will emphasize the role of basic scientific research in improving our understanding of natural phenomena and the planet's response to anthropogenic stressors.