Collaborative research: Constraining the global ocean nitrogen cycle with multiple tracers in a biogeochemical inverse model

合作研究：在生物地球化学反演模型中使用多种示踪剂约束全球海洋氮循环

• 批准号: 1131548
• 负责人: Curtis Deutsch
• 金额: $ 38.08万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1131548&HistoricalAwards=false
• 关键词: Collaborative; research; Constraining; global; ocean

Nitrogen (N) biogeochemical cycling in the marine environment is subject to complex biological and environmental feedbacks with unknown climate sensitivities. Past studies have attempted to characterize the marine N inventory using biogeochemical tracers, such as nutrient stoichiometry, nitrogen isotopes and N2 gas, but these studies have been a snapshot, focusing on a single process in a specific region of the ocean at a time. Such studies were forced to ignore other important and related controlling mechanisms. To resolve the magnitude and type of environmental controls on the processes that influence the N inventory, processes need to be considered simultaneously. Researchers from the University of California at Los Angeles propose to model the spatial distributions and rates of the primary N budget fluxes. In order to derive a global marine N budget, researchers propose to use an inverse model framework that is consistent with all available tracer data. The global ocean circulation model will contain biogeochemical cycles of tracers and will be constrained to optimize the fit to physical tracers (T, S, 14-C-age, CFCs). To examine how environmental variables affect the magnitude of each flux, they will be regressed against the modeling results, providing insight into the effects of anticipated climate change on the N budget. Furthermore, analysis of the inverse solution's error structure will allow researchers to examine the validity of tracer-related assumptions. This work could set up a statistically rigorous framework that will enable researchers to assimilate rapidly developing data streams and will highlight areas in the oceans where data is lacking, allowing resources to be used strategically. The project will provide education and training for undergraduate and graduate students, as well as a post-doc, and will provide important information and insights into the biogeochemical cycling of N necessary to understand the impact of changing climate on ocean processes.

海洋环境中氮的生物地球化学循环受到复杂的生物和环境反馈的影响，其气候敏感性未知。过去的研究曾试图使用海洋地球化学示踪剂，如营养化学计量，氮同位素和N2气体，来表征海洋氮库存，但这些研究一直是快照，集中在一个单一的过程中的一个特定区域的海洋。这些研究被迫忽略了其他重要的相关控制机制。要解决的规模和类型的环境控制的过程中，影响N库存，过程需要同时考虑。来自洛杉矶的加州大学的研究人员建议模拟初级N收支通量的空间分布和速率。为了获得全球海洋氮预算，研究人员建议使用一个逆模型框架，是与所有可用的示踪剂数据一致。全球海洋环流模式将包含示踪剂的地球化学循环，并将受到约束，以优化物理示踪剂（T，S，14-C年龄，CFCs）的拟合。为了研究环境变量如何影响每个通量的大小，他们将回归对建模结果，提供洞察预期的气候变化对N预算的影响。此外，逆解的误差结构的分析将允许研究人员检查示踪剂相关假设的有效性。这项工作可以建立一个严格的统计框架，使研究人员能够吸收迅速发展的数据流，并突出缺乏数据的海洋地区，从而能够战略性地使用资源。该项目将为本科生和研究生以及博士后提供教育和培训，并将为了解气候变化对海洋过程的影响所需的N的地球化学循环提供重要信息和见解。