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BERNO 3 7（7-Be）方法，作为国际北极气候研究多学科漂流观测站考察的一部分，以评估气溶胶沉积的季节性变化。这是第一个现代的机会，这样一个全面的研究每年沉积通量的微量元素（TE）进入北冰洋/冰生态系统。7-Be和气溶胶TE测量的组合已被证明是一种有效的工具，用于估计大气输入的TE在偏远的海洋地区，附近的陆基收集站点不存在。在这项工作中产生的数据将允许地面实况模型的气溶胶沉积和大气输入的TE。大气沉降是大气中微量元素，特别是汞（Hg）进入北冰洋的主要途径，最近的文献表明，大气沉积的生物必需的微量元素，如铁（Fe），可以发挥主要作用，在控制生物生产力在北极。大气传输和沉积的气溶胶是一个重要的输送机制，天然和污染物的微量元素（到北极。现有数据表明，汞、铅和硒等污染元素的大气沉积可能是这些元素进入北极的主要来源，可能的来源是欧洲、俄罗斯和亚洲与化石燃料燃烧有关的人为工业或发电厂排放。生物必需微量元素（如Mn、Fe、Co、Ni、Cu、Zn）的大气输入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，北极可能也是如此。这些投入对生态系统甚至人类健康都有重大影响。对这一投入进行评估是困难的，因为偏远海洋区域的沉积率测量很少，而在北极地区进行测量尤其令人生畏，因为恶劣的条件和有限的研究平台使得难以定期获得质量受控的降水和气溶胶化学测量结果。这项研究将提供气溶胶TE（总量和可溶性）的年度大气沉积通量估计值，包括具有地球化学重要性的TE以及污染物种类。还将评估各种集水区（冰、水、雪、融化池）之间微量元素沉积分区的季节性演变。这项工作将涉及测量7-Be库存，7-Be气溶胶活动和气溶胶浓度的TE。该项目将是MOSAiC考察的一个组成部分，MOSAiC考察是一项国际倡议，其动机是北极气候系统的快速演变，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，并已被国际和美国机构认可为一个急需的项目，以提供支持耦合模型开发所需的不断变化的北极中部系统的基础信息。能够提供有关的臭氧当量对北冰洋的大气输入的估计将广泛有助于化学海洋学领域，包括了解人为对该地区的影响和臭氧当量的大气输入在北冰洋生态中的作用。牵头机构是该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一项指导计划。该团队将录制简短的讲座和视频日志，可用于他的课程的未来迭代，以介绍重要的海洋学概念，并为他的学生提供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，外联活动将强调基础科研在提高我们对自然现象和地球对人为压力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.