Collaborative Research: Mesoscale Drivers of Oxygen in the Tropical Pacific

合作研究：热带太平洋氧气的中尺度驱动因素

• 批准号: 1948718
• 负责人: Matthew Long
• 金额: $ 12.99万
• 依托单位: University Corporation For Atmospheric Res
• 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: 2020-03-15 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1948718&HistoricalAwards=false
• 关键词: Collaborative; Research; Mesoscale; Drivers; Oxygen

The tropical Pacific Ocean is home to rich marine biodiversity and abundant fisheries. It is also the most oxygen-deficient basin in the world, hosting the world’s largest oxygen minimum zones (OMZs). The northern and southern tropical Pacific OMZs are separated by oxygen-rich waters along the equator that provide important habitable space for open ocean fisheries whose feeding behavior is limited by the depth at which oxygen levels decrease below uninhabitable thresholds. Characterizing the processes that control the depth of this low oxygen threshold is important to understanding ecosystem dynamics and to predicting and managing fisheries in this region. The primary goal for this project is to understand the role of regional physical processes in setting the 3-dimensional structure of oxygen in the equatorial Pacific and its changes on seasonal and interannual time scales. The investigators will use a combination of computer models and existing observations to describe the role that regional circulation patterns play in maintaining the volume and oxygen content of the Pacific OMZs. These include global models of ocean circulation and biological and chemical processes controlling the OMZ, as well as models that focus on regional scale features of ocean circulation (such as eddies) and that are informed by observations. The oceanic oxygen cycle integrates physical, biological, and chemical phenomena, making it an ideal curriculum topic for applying Next Generation Science Standards (NGSS) into K-12 classrooms. In this project, the investigators will work closely with NGSS early implementers from the local school districts to introduce this project’s research questions, knowledge, and relevant data and visualization tools into the lesson plans, exposing students and teachers directly to the scientific process. A major knowledge gap concerns the role of the equatorial current system (ECS) and tropical instability vortices (TIVs) in ventilating the OMZs, and the extent to which oxygen supply by these ventilation pathways is compensated by their effects on nutrient transport, productivity, and respiration rates, motivating the following questions: 1. How does the equatorial current system and its interaction with mesoscale eddies modulate the boundaries and ventilation of the OMZs? 2. What governs the seasonal to interannual variability of OMZ ventilation in this region? 3. Through what physical and biogeochemical mechanisms do TIVs influence equatorial Pacific oxygen? A central hypothesis for this proposal is that lateral transport by the Equatorial Undercurrent and TIV-mediated fluxes play a dominant role in setting the mean oxygen structure and variability of the upper equatorial Pacific. These questions will be examined using a hierarchy of models of various configurations, including an eddy resolving and coarse global model, an eddy resolving data-assimilating regional model of the tropical Pacific, and Lagrangian analysis. The work is expected to i) elucidate the mechanisms coupling oxygen to ocean circulation and climate variability in the tropical Pacific, ii) inform drivers of OMZ biases in models, and iii) guide observing needs including the on-going Tropical Pacific Observing System (TPOS 2020) efforts and future deployments of biogeochemical (BGC) Argo floats in this region.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.

热带太平洋是丰富的海洋生物多样性和丰富渔业的所在地。它也是世界上最大的氧气缺陷盆地，拥有世界上最大的氧最小区（OMZ）。北部和南部热带太平洋OMZ被沿平等的富含氧气的水隔开，为开放海洋渔业提供了重要的宜居空间，其饲料行为受到氧气水平降低低于无法居住的阈值的深度的限制。表征控制该低氧阈值深度的过程对于理解生态系统动力学以及预测和管理该地区的渔业很重要。该项目的主要目的是了解区域物理过程在设定赤道太平洋中氧气的三维结构及其在季节性和年际时间尺度上的变化中的作用。研究人员将使用计算机模型和现有观察结果的组合来描述区域循环模式在维持太平洋OMZ的体积和氧气含量中所起的作用。其中包括控制OMZ的全球海洋循环，生物和化学过程模型，以及关注海洋循环（例如涡流）的区域尺度特征的模型，并通过观测来告知。海洋氧气周期将物理，生物学和化学现象整合在一起，使其成为将下一代科学标准（NGSS）应用于K-12教室的理想课程主题。在该项目中，调查人员将与NGSS的早期实施者紧密合作，以将该项目的研究问题，知识以及相关数据和可视化工具介绍到课程计划中，将学生和老师直接暴露于科学过程中。主要的知识差距涉及对位置系统（EC）和热带不稳定性涡流（TIV）在通风OMZ中的作用，以及这些通风途径通过这些通风途径的氧气供应的程度，其氧气对养分的运输，生产力和呼吸速度的影响弥补了其对以下问题的影响，并激发了以下问题的范围：1。 omzs？ 2。是什么控制了该地区OMZ通风的季节性变异性？ 3。通过物理和生物地球化学机制，TIV会影响太平洋氧气？该提案的一个中心假设是，赤道暗流和TIV介导的通量的横向转运在设定上等差异太平洋上含量的氧结构和可变性方面起主要作用。这些问题将使用各种配置模型的层次结构进行检查，包括涡流解决和粗糙的全局模型，热带太平洋的涡流解决数据鉴定区域模型以及Lagrangian分析。 The work is expected to i) elucidate the mechanisms coupling oxygen to ocean circulation and climate variability in the tropical Pacific, ii) inform drivers of OMZ biases in models, and iii) guide observing needs including the on-going Tropical Pacific Observing System (TPOS 2020) effort and future deployments of biogeochemical (BGC) Argo floats in this region.This award reflects NSF's法定使命，并通过评估诚实地认为，使用基金会的智力优点和更广泛的影响审查标准。