US GEOTRACES Arctic Section: Characterization, Sampling and Analysis of the Sea Ice Environment in the Arctic Ocean

在这个项目中，一组参与2015年美国地理痕迹北极考察的调查人员将描述和量化海冰作为北冰洋痕量金属和放射性同位素的储存库和运输者的作用。与国际地质勘测计划中的其他多国倡议一样，美国北极探险的目标是确定控制海洋中关键微量元素和同位素分布的过程和通量，并确定这些分布对不断变化的环境条件的敏感性。一些微量元素对生命是必不可少的，另一些是已知的生物毒素，还有一些很重要，因为它们可以用作海洋中各种物理、化学和生物过程的示踪剂。海冰小组将与一个由海洋微量元素专家组成的多机构团队合作，将重点放在冰作为一个水库的重要性上，它可以在一个地点积累微量元素，然后在另一个地点释放它们。该项目还将为阿拉斯加大学费尔班克斯校区至少一名研究生提供培训和支持，并为当地社区(包括土著居民)提供多项校外公共教育倡议。美国地质调查局北极段将穿越受海冰过程影响的水域，并显示出显著的化学和生物梯度。在横断面上将遇到不同年代和来源的海冰，这为描述不同历史的海冰中感兴趣的微量元素提供了一个独特的机会。北极海冰中感兴趣的微量元素的分布尚未确定，但预计会有很大的差异，这项研究将调查决定这种变化的重要因素，从而对北极环境中痕量元素的迁移和分布很重要。进入浮冰将允许对雪盖内的大气沉积进行微量金属清洁采样，并确定与海冰接触的表层水域的特征。该项目将涉及从海冰环境中采集微量金属清洁样本，以高分辨率测量冰下雪、海冰和海水中溶解的和颗粒状的关键微量元素，并确定海冰的物理和辅助化学特征，以便有助于量化输入北冰洋的微量元素。将收集来自海冰环境的样本，并将其均质化，以便分发给科学界。事实上，海冰集团开发的痕量金属清洁冰芯将促进海冰化学特征的表征，使他们处于收集海冰样本并将其分发给GEOTRACES社区的独特地位。

In this project, a group of investigators participating in the 2015 U.S. GEOTRACES Arctic expedition will characterize and quantify the role of sea ice as a repository and transporter of trace metals and radioisotopes in the Arctic Ocean. In common with other multinational initiatives in the International GEOTRACES Program, the goals of the U.S. Arctic expedition are to identify processes and quantify fluxes that control the distributions of key trace elements and isotopes in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions. Some trace elements are essential to life, others are known biological toxins, and still others are important because they can be used as tracers of a variety of physical, chemical, and biological processes in the sea. Working alongside a multi-institutional team of ocean trace element experts, the sea ice group will focus its attention on the importance of ice as a reservoir that can accumulate trace elements in one locale and release them in another. This project will also provide for the training and support of at least one graduate student at the University of Alaska Fairbanks Campus as well as multiple extramural public educational initiatives for local communities (including indigenous populations).The U.S.GEOTRACES Arctic section will traverse waters impacted by sea ice processes, and exhibiting significant chemical and biological gradients. Sea ice of various ages and provenance will be encountered along the transect, presenting a unique opportunity to characterize trace elements of interest in sea ice with differing histories. The distribution of trace elements of interest in Arctic sea ice has not yet been determined, but it is expected to vary widely, and this study will investigate factors important in determining this variability, and thus important in the transport and distribution of trace elements in the Arctic environment. Access to ice floes will allow trace-metal-clean sampling of atmospheric deposition within snow cover, and characterization of surface waters in contact with sea ice. The project will involve collection of trace-metal-clean samples from the sea ice environment to make high-resolution measurements of dissolved and particulate key trace elements from snow, sea ice and seawater underneath the ice, and to determine sea ice physical, and ancillary chemical characteristics in order to contribute towards the quantification of trace element input to the Arctic Ocean. Samples from the sea ice environment will be collected and homogenized for distribution to the scientific community. In fact, the development of a trace metal clean ice corer by the sea ice group will facilitate the characterization of sea ice chemistry, putting them in a unique position to collect, and distribute sea ice samples to the GEOTRACES community.