Collaborative Research: Submesoscale-Resolving Large Eddy Simulations Using Reduced Biogeochemical Models

合作研究：使用简化的生物地球化学模型进行亚尺度解析大涡模拟

• 批准号: 1924658
• 负责人: Kyle Niemeyer
• 金额: $ 24.79万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1924658&HistoricalAwards=false
• 关键词: Collaborative; Research; Submesoscale; Resolving; Large

Improved understanding of upper ocean biogeochemistry requires a comprehensive look at the interactions between chemical tracers and turbulence at scales smaller than one kilometer (also termed "submesoscale"), but modeling chemical tracers and processes at these small scales requires a tremendous amount of computing power and time. As a result, new reduced biogeochemical models, solved in novel ways, must be developed to perform large eddy simulations (LES) of coupled biogeochemistry and physical processes at these scales. In the proposed project, techniques adapted from the field of combustion for the reduction of large chemical kinetics mechanisms will, for the first time, be used to reduce the size of large ocean biogeochemical models. This interdisciplinary research effort will be undertaken by a collaborative team consisting of an expert in numerical simulations of both reacting and oceanographic flows, a biological oceanographer with extensive knowledge of ocean biogeochemistry, and an expert in chemical model reduction and solution. The tools developed in this project will be made available to the broader oceanographic community, and involvement of interdisciplinary PhD students will expose a new generation to computational methods in oceanography and the Earth sciences. The project will provide research experience and mentorship to undergraduate students, particularly those under-represented in STEM, by designing projects derived from, and complementary to, the proposed research. Ultimately, this project will benefit society through improvements to Earth system models (ESMs) used to study climate, resulting in more accurate predictions of future climate impacts on human health, safety, and property. Solution of the reduced models will be performed on graphical processing units (GPUs) using a high-order Runge-Kutta-Chebyshev (RKC) time integration scheme. This project will culminate in the simulation of realistic ocean scenarios and comparisons will be made with observational data from the Drake Passage to determine the role of submesoscale processes in generating small-scale patchiness in the partial pressure of carbon dioxide. Ultimately, insights obtained from the LES will be used to develop a better understanding of the interactions between small-scale turbulence and biogeochemistry in the upper ocean, including the characteristics, dynamical origins, and effects of tracer patchiness. Integration of complex biogeochemical models within high-fidelity LES has previously been exceptionally difficult, but the proposed model reduction, as well as the use of GPUs and the high-order RKC integrator, will enable high-resolution studies of fully-coupled turbulent and biogeochemical processes at submesoscales. These improvements will be made possible by leveraging techniques from chemical kinetics modeling for combustion, where reduction and integration of large chemical mechanisms in high-fidelity simulations has been common for nearly a decade. The proposed simulation effort will provide insights into the effects of submesoscale turbulence, including wave-driven Langmuir turbulence, on the upper-ocean carbon cycle, and will inform the future development of improved ESMs. In particular, interactions between submesoscale turbulence and biogeochemical tracers are thought to be the cause of tracer patchiness and require substantial further study to develop more accurate subgrid-scale parameterizations for ESMs. Moreover, simulations of the Drake Passage will provide concrete insights and understanding of tracer patchiness for realistic conditions.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.

对上海生物地球化学的了解得以提高，需要全面了解化学示踪剂和小于一公里的尺度的湍流之间的相互作用（也称为“ submessocale”），但是在这些小尺度上对化学示踪剂和过程进行建模需要大量的计算能力和时间。结果，必须开发出新的减少生物地球化学模型，以在这些尺度上对生物地球化学和物理过程进行大型涡流模拟（LES）。在拟议的项目中，从燃烧领域改编而成，以减少大型化学动力学机制，这将首次使用来减少大海洋生物地球化学模型的大小。这项跨学科的研究工作将由一个合作团队进行，该团队由对反应和海洋学流量的数值模拟专家组成，一位生物海洋学家，对海洋生物地球化学的广泛了解以及化学模型还原和解决方案的专家。该项目开发的工具将提供给更广泛的海洋学社区，跨学科博士学位学生的参与将使新一代海洋学和地球科学的计算方法暴露。该项目将通过设计源自拟议的研究的项目和补充的项目，为本科生，尤其是STEM的人数不足的学生提供研究经验和指导。最终，该项目将通过改善用于研究气候的地球系统模型（ESM）的社会受益，从而更准确地预测了未来气候对人类健康，安全和财产的影响。还原模型的解决方案将使用高阶Runge-Kutta-Chebyshev（RKC）时间整合方案在图形处理单元（GPU）上执行。该项目将在仿真逼真的海洋场景中达到最终形象，并将与Drake段落的观察数据进行比较，以确定子阶级过程在产生二氧化碳部分压力中产生小规模斑块方面的作用。最终，从LES获得的见解将被用来更好地理解上海上小规模的湍流和生物地球化学之间的相互作用，包括特征，动力学起源和示踪剂斑点的影响。在高保真性LES内的复杂生物地球化学模型的整合以前非常困难，但是所提出的模型还原以及GPU和高阶RKC集成剂的使用将促进对群的全面耦合湍流和生物地球化学过程的高分辨率研究。通过利用化学动力学建模的技术进行燃烧，将实现这些改进，在近十年中，高保真模拟中大型化学机制的降低和整合一直很常见。提出的仿真工作将提供有关集群湍流影响的见解，包括波动的Langmuir湍流，对上海洋碳循环的影响，并将为ESMS改善的未来发展提供信息。特别是，尺度湍流与生物地球化学示踪剂之间的相互作用被认为是示踪剂斑块的原因，需要进行大量进一步的研究以开发更准确的亚网格尺度参数化的ESMS。此外，对Drake段落的模拟将提供具体的见解，并了解对现实状况的示踪剂斑点。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估来提供支持。

项目成果

BFM17 v1.0: a reduced biogeochemical flux model for upper-ocean biophysical simulations

BFM17 v1.0：用于上层海洋生物物理模拟的简化生物地球化学通量模型

• DOI: 10.5194/gmd-14-2419-2021
• 发表时间: 2021
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: Smith, Katherine M.;Kern, Skyler;Hamlington, Peter E.;Zavatarelli, Marco;Pinardi, Nadia;Klee, Emily F.;Niemeyer, Kyle E.
• 通讯作者: Niemeyer, Kyle E.