Collaborative research: Understanding the spatial and temporal variability of dissolved oxygen through a hierarchy of models.

合作研究：通过模型层次结构了解溶解氧的空间和时间变化。

• 批准号: 1242313
• 负责人: Takamitsu Ito
• 金额: $ 12.62万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1242313&HistoricalAwards=false
• 关键词: Collaborative; research; Understanding; spatial; temporal

Abstract In this project ocean modelers at The University of California at Los Angeles and Colorado State University will develop a new theoretical framework for understanding and predicting the responses of oceanic oxygen to wide range of climate variability. Recent observations of decadal oxygen changes of in the upper ocean, which now have been documented in every ocean basin, motivate several questions regarding the underlying mechanisms. How does dissolved oxygen respond to atmospheric forcing at different time scales? How do the temporal spectrum and spatial patterns relate to that of its driving forces, both physical and biological, and to the coupling between them? Modeling studies on long-term trends and basin-scale variability revealed that dissolved oxygen is highly sensitive to both physical and biological processes, and it has been suggested as a tracer of climate change in the oceans. However, mechanistic understanding of underlying causes are far from complete, and fuller elucidation of the large-scale modes of oxygen variability is therefore needed, particularly as new data is rapidly increasing. The research team hypothesizes that the physical and biological drivers of oxygen changes are modulated by the thermocline ventilation in the upper ocean, leading to enhanced large-scale, low frequency variability. The theory leads to novel hypotheses for explaining two recurring and general observations: that O2 changes are so prevalent at decadal time scales and are focused in waters occupying a common position in the water column, namely the base of the ventilated thermocline. They plan to evaluate these predictions using a hierarchy of models ranging from a one-dimensional isopycnal model to a state-of-the-art eddy-permitting global ocean model with ecosystem and biogeochemistry components. The work plan will involve comparison of patterns across a hierarchy of models, illuminating fundamental and non-model dependent dynamics of the oceanic oxygen cycle. This project culminates in the application of our theoretical and modeling approach to the Observing System Simulation Experiments (OSSEs) for the proposed global implementation of ARGO-O2 project to develop future observational strategies. This will be a major step toward building a set of tools for understanding the types of O2 variability found in the real world, and laying the groundwork for analyzing a wide range of observational and modeling data for this important tracer. Broader Impacts: The researchers anticipate that this work will shed light on hypoxia as an emerging problem in the ocean of strategic importance to fisheries managers and marine conservation efforts. Through the proposed OSSEs, this project will assist in the formulation of optimal observational strategies for the international efforts to develop the global array of O2 sensors on ARGO floats. The results are also expected to provide a mechanistic basis for estimating global scale losses of O2 from such irregular sampling networks, thus reducing a key uncertainty in the quantification of the partitioning of anthropogenic CO2 uptake between the land and the oceans. Finally, the project will provide for the training and support of two beginning graduate students, as well as outreach activities at Coloado Statue University on oceans and climate science for K-12 through graduate students and for the general public.

该项目的摘要在加利福尼亚大学洛杉矶和科罗拉多州立大学的海洋建模者将开发一个新的理论框架，以理解和预测海洋氧对广泛气候变异性范围的反应。最近在每个海洋盆地中都记录的上海中衰老的氧气变化的最新观察结果激发了有关潜在机制的几个问题。溶解的氧气如何应对不同时间尺度的大气强迫？时间频谱和空间模式与其物理和生物学的驱动力以及它们之间的耦合有何关系？对长期趋势和盆地规模的可变性进行建模研究表明，溶解的氧气对物理和生物学过程高度敏感，并且已被认为是海洋气候变化的示踪剂。但是，对潜在原因的机械理解远非完整，因此需要更全面地阐明大规模的氧变化模式，尤其是随着新数据迅速增加。研究团队假设氧气变化的物理和生物驱动因素是由上海上的热跃层通风调节的，从而导致大规模的低频变异性增强。该理论导致了解释两个反复观察和一般性观察的新假设：在十年时间尺度上，O2变化是如此普遍，并且集中在水柱中占据共同位置的水域，即通风热跃层的基础。他们计划使用从一维同相模型到具有生态系统和生物地球化学组件的最先进的涡流全球海洋模型的模​​型等级来评估这些预测。该工作计划将涉及模型层次结构的模式的比较，从而阐明了海洋氧循环的基本和非模型依赖性动力学。该项目最终将我们的理论和建模方法应用于观察系统仿真实验（OSSES），用于拟议的ARGO-O2项目的全球实施，以制定未来的观察策略。这将是迈向建立一组工具的重要一步，以了解现实世界中发现的O2变异性类型，并为分析该重要示踪剂的广泛观察和建模数据奠定了基础。更广泛的影响：研究人员预计，这项工作将阐明缺氧是对渔业经理和海洋保护工作的战略重要性的新兴问题。通过拟议的OSSES，该项目将有助于制定最佳的观察策略，以制定国际努力，以开发Argo Floats上的全球O2传感器。预计该结果还将为从这种不规则采样网络中估算O2的全球尺度损失提供机械基础，从而减少了对土地和海洋之间人为CO2摄取的分配量化的关键不确定性。最后，该项目将通过研究生和公众为K-12的海洋和气候科学雕像，对两名初学者的培训和支持，以及在Coloado雕像大学的外展活动。