US GEOTRACES Pacific Meridional Transect: Determination of the air-sea exchange of inorganic and methylated mercury in the anthropogenically-impacted and remote Pacific Ocean

美国 GEOTRACES 太平洋经线横断面：测定受人为影响的偏远太平洋中无机汞和甲基化汞的海气交换

• 批准号: 1736659
• 负责人: Robert Mason
• 金额: $ 28.51万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-10-01 至 2020-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1736659&HistoricalAwards=false
• 关键词: US; GEOTRACES; Pacific; Meridional; Transect

Human activity has greatly increased the amount of mercury (Hg) in the environment, and particularly in the surface ocean. Most of the Hg enters the ocean from the atmosphere as a gas, on particles, or in precipitation. Complex physical and chemical processes at the interface between the ocean and atmosphere control the amount of Hg that is retained and therefore that can ultimately accumulate in seafood. Methylmercury (MeHg) is a chemical form of Hg that is commonly retained in organisms and impacts the health and development of humans and wildlife. This research will assess concentrations of Hg together with its "methyl" forms in the atmosphere and surface ocean at sea from Alaska to Tahiti. The spatial extent of the cruise will allow comparison of the air-sea exchange and concentrations of mercury in both the North Pacific where human emissions are large and in remote regions with minimal human impact. The researchers will use established techniques and develop new methods to examine the fate and transport of mercury within the surface ocean. These findings will contribute key Hg data to the GEOTRACES program and thus enhance its overall impact as part of an extensive marine trace element study. Findings will have potential to inform public policy and global environmental treaties related to Hg, thus providing data to evaluate human risk from Hg in present and future climate scenarios. Educational impact will include support for a graduate student and their dissertation using the field data, as well as several undergraduates that will gain high level, hands-on research experience. The research will take advantage of recent analytical advances that enable high resolution determination of the concentrations and forms of inorganic Hg in the surface ocean and atmosphere. The analytical approach will also be expanded to include measurements of methylated Hg compounds, including MeHg and dimethylmercury. These measurements, and ancillary data collected during the GEOTRACES Pacific Meridional Transect cruise, will allow assessment of both atmospheric input and in situ oceanic loss for the dominant forms of inorganic and methylated Hg. Exchange will also be evaluated in the context of the suite of environmental variables collected by collaborators during the cruise. The resulting data will help assess the long-term impact of anthropogenic inputs of Hg to the atmosphere and ocean, and the factors that influence the loss of Hg from the ocean by gas evasion. The studies will build on previous results obtained as part of the GEOTRACES program and other NSF-funded studies, adding novel measurements and building an enhanced understanding of the sources and sinks of Hg to the open ocean.

人类活动大大增加了环境中的汞含量，特别是在海洋表层。大部分汞以气体、颗粒或降水的形式从大气层进入海洋。海洋与大气界面复杂的物理和化学过程控制着汞的留存量，因此汞最终会在海产品中积累。 甲基汞（MeHg）是汞的一种化学形式，通常保留在生物体中，影响人类和野生动物的健康和发育。这项研究将评估从阿拉斯加到塔希提岛的大气和海洋表层中汞及其“甲基”形式的浓度。 此次航行的空间范围将允许对人类排放量较大的北太平洋和人类影响最小的偏远地区的海气交换和汞浓度进行比较。研究人员将使用现有技术并开发新方法来研究海洋表面汞的命运和运输。这些发现将为GEOTRACES方案提供关键的汞数据，从而加强其作为广泛的海洋微量元素研究的一部分的总体影响。研究结果将有可能为公共政策和与汞有关的全球环境条约提供信息，从而为评估当前和未来气候情景下汞对人类的风险提供数据。 教育影响将包括支持研究生和他们的论文使用现场数据，以及几个本科生，将获得高水平，动手研究经验。这项研究将利用最新的分析进展，能够高分辨率地确定海洋表面和大气中无机汞的浓度和形式。 分析方法也将扩大，以包括甲基化汞化合物的测量，包括甲基汞和二甲基汞。这些测量结果以及GEOTRACES太平洋经向样带巡航期间收集的辅助数据，将有助于评估主要无机汞和甲基化汞的大气输入和海洋原位损失。 还将根据合作者在航行期间收集的一系列环境变量对交流进行评价。由此产生的数据将有助于评估人类活动向大气和海洋输入汞的长期影响，以及影响汞因气体逃逸而从海洋中流失的因素。 这些研究将建立在GEOTRACES项目和其他国家科学基金会资助的研究的基础上，增加新的测量方法，并加深对公海汞的来源和汇的理解。

项目成果

Comparison of reactive gaseous mercury measured by KCl-coated denuders and cation exchange membranes during the Pacific GEOTRACES GP15 expedition

太平洋 GEOTRACES GP15 探险期间 KCl 涂层剥蚀器和阳离子交换膜测量的活性气态汞的比较

• DOI: 10.1016/j.atmosenv.2020.117973
• 发表时间: 2021
• 期刊: Atmospheric Environment
• 影响因子: 5
• 作者: He, Yipeng;Mason, Robert P.
• 通讯作者: Mason, Robert P.