Collaborative Research: Management and Implementation of US GEOTRACES GP17 Section: South Pacific and Southern Ocean (GP17-OCE)

合作研究：美国GEOTRACES GP17部分的管理和实施：南太平洋和南大洋（GP17-OCE）

• 批准号: 2023206
• 负责人: Jessica Fitzsimmons
• 金额: $ 50.28万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-10-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2023206&HistoricalAwards=false
• 关键词: Collaborative; Research; Management; Implementation; US

This award will support the management and implementation of a research expedition from Tahiti to Chile that will enable sampling for a broad suite of trace elements and isotopes (TEI) across oceanographic regions of importance to global nutrient and carbon cycling as part of the U.S. GEOTRACES program. GEOTRACES is a global effort in the field of Chemical Oceanography, the goal of which is to understand the distributions of trace elements and their isotopes in the ocean. Determining the distributions of these elements and isotopes will increase understanding of processes that shape their distributions, such as ocean currents and material fluxes, and also the processes that depend on these elements, such as the growth of phytoplankton and the support of ocean ecosystems. The proposed cruise will cross the South Pacific Gyre, the Antarctic Circumpolar Current, iron-limited Antarctic waters, and the Chilean margin. In combination with a proposed companion GEOTRACES expedition on a research icebreaker (GP17-ANT) that will be joined by two overlapping stations, the team of investigators will create an ocean section from the ocean’s most nutrient-poor waters to its highly-productive Antarctic polar region – a region that plays an outsized role in modulating the global carbon cycle. The expedition will support and provide management infrastructure for additional participating science projects focused on measuring specific external fluxes and internal cycling of TEIs along this section. The South Pacific Gyre and Pacific sector of the Southern Ocean play critical roles in global water mass circulation and associated global transfer of heat, carbon, and nutrients, but they are chronically understudied for TEIs due to their remote locale. These are regions of strong, dynamic fronts where sub-surface water masses upwell and subduct, and biological and chemical processes in these zones determine nutrient stoichiometries and tracer concentrations in waters exported to lower latitudes. The Pacific sector represents an end member of extremely low external TEI surface fluxes and thus an important region to constrain inputs from the rapidly-changing Antarctic continent. Compared to other ocean basins, TEI cycling in these regions is thought to be dominated by internal cycling processes such as biological uptake, regeneration, and scavenging, and these are poorly represented in global ocean models. The cruise will enable funded investigators to address research questions such as: 1) what are relative rates of external TEI fluxes to this region, including dust, sediment, hydrothermal, and cryospheric fluxes? 2) What are the (micro) nutrient regimes that support productivity, and what impacts do biomass accumulation, export, and regeneration have on TEI cycling and stoichiometries of exported material? 3) What are TEI and nutrient stoichiometries of subducting water masses, and how do scavenging and regeneration impact these during transport northward? This management project has several objectives: 1) plan and coordinate a 55-day research cruise in 2021-2022; 2) use both conventional and trace-metal ‘clean’ sampling systems to obtain TEI samples, as well as facilitate sampling for atmospheric aerosols and large volume particles and radionuclides; 3) acquire hydrographic data and samples for salinity, dissolved oxygen, algal pigments, and macro-nutrients; and deliver these data to relevant repositories; 4) ensure that proper QA/QC protocols, as well as GEOTRACES intercalibration protocols, are followed and reported; 5) prepare the final cruise report to be posted with data; 6) coordinate between all funded cruise investigators, as well as with leaders of proposed GP17-ANT cruise; and 7) conduct broader impact efforts that will engage the public in oceanographic research using immersive technology. The motivations for, and at-sea challenges of this work will be communicated to the general public through creation of immersive 360/Virtual Reality experiences, via a collaboration with the Texas A&M University Visualization LIVE Lab. Through Virtual Reality, users will experience firsthand what life and TEI data collection at sea entail. Virtual reality/digital games and 360° experiences will be distributed through GEOTRACES outreach websites, through PI engagement with local schools, libraries, STEM summer camps, and adult service organizations, and through a collaboration with the National Academy of Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项将支持管理和实施从塔希提岛到智利的研究考察，作为美国 GEOTRACES 计划的一部分，该考察将能够在对全球营养物和碳循环具有重要意义的海洋区域中采样广泛的微量元素和同位素 (TEI) GEOTRACES 是化学海洋学领域的一项全球性努力，其目标是了解海洋中微量元素及其同位素的分布并确定这些元素的分布。同位素将增进对影响其分布的过程（例如洋流和物质通量）以及依赖于这些元素的过程（例如浮游植物的生长和海洋生态系统的支持）的了解。拟议的巡航将穿越南太平洋。环流、南极绕极流、含铁量有限的南极水域和智利边缘，与拟议的研究破冰船 (GP17-ANT) 上的 GEOTRACES 探险相结合。通过两个重叠的站，研究小组将创建一个从海洋营养最贫乏的水域到生产力高的南极地区的海洋区域，该区域在调节全球碳循环方面发挥着巨大作用。支持并为其他参与的科学项目提供管理基础设施，重点是测量该部分沿线的 TEI 的特定外部通量和内部循环。 南太平洋环流和南大洋的太平洋部分在全球水团循环和相关的全球热量传递中发挥着关键作用。 ,碳和营养物，但由于其位置偏远，长期对 TEI 的研究不足。这些区域具有强烈的动态锋面，其中地下水团上升和俯冲，这些区域的生物和化学过程决定了营养物化学计量和示踪剂浓度。与其他海洋相比，太平洋区域是外部 TEI 表面通量极低的区域，因此是限制快速变化的南极大陆输入的重要区域。据认为，这些区域的 TEI 循环主要是生物吸收、再生和清除等内部循环过程，而这些过程在全球海洋模型中很少得到体现。这次航行将使受资助的研究人员能够解决以下研究问题：1。 ) 该区域的外部 TEI 通量的相对速率是多少，包括灰尘、沉积物、热液和冰冻圈通量？ 2) 支持生产力的（微）营养状况是什么，以及生物量积累、输出、 3) 俯冲水团的 TEI 和营养物化学计量是什么？在向北运输过程中，清除和再生对这些有何影响？ 2021-2022 年为期 55 天的研究巡航；2) 使用传统和微量金属“清洁”采样系统来获取 TEI 样品，如以及促进大气气溶胶和大体积颗粒和放射性核素的采样； 3) 获取盐度、溶解氧、藻类色素和宏观营养物的水文数据和样本； 4) 确保适当的质量保证/遵循并报告 QC 协议以及 GEOTRACES 相互校准协议； 5) 准备最终的巡航报告并发布数据； 6) 在所有受资助的巡航调查员以及领导者之间进行协调拟议的 GP17-ANT 巡航；7) 开展更广泛的影响工作，利用沉浸式技术让公众参与海洋学研究 这项工作的动机和海上挑战将通过创建沉浸式 360 度向公众传达。 /虚拟现实体验，通过与德克萨斯 A&M 大学可视化 LIVE 实验室的合作，用户将亲身体验海上生活和 TEI 数据收集所需的内容。 360° 体验将通过 GEOTRACES 外展网站、PI 与当地学校、图书馆、STEM 夏令营和成人服务组织的合作以及与美国国家科学院的合作进行分发。该奖项反映了 NSF 的法定使命，并被视为值得通过使用基金会的智力优点和更广泛的影响审查标准进行评估来支持。