CMG Research: Collaborative Research on Models of Sub-Grid Scale Turbulence in Earth's Core and the Geodynamo

CMG 研究：地核次网格尺度湍流模型和地球发电机的合作研究

• 批准号: 0222205
• 负责人: David Loper
• 金额: $ 5.51万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-15 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0222205&HistoricalAwards=false
• 关键词: CMG; Research; Collaborative; Models; Sub

EAR-0222205LoperEarth's dynamo, which is responsible for the geomagnetic field, is a geosystem involving a broad range of interacting scales, a complex geometry and a rich variety of physical processes. Numerical simulations resolve only the largest-scale features; most parameterizations of the smaller, subgrid scale processes simulate dissipative processes only, and are incapable of simulating non-dissipative processes which affect transfers of energy among differing spatial scales. Exceptions to this statement are the recently developed similarity and Navier-Stokes-alpha models. Core dynamics is strongly affected by the action of the Coriolis and Lorentz forces, making the fields both anisotropic and non-local. Recent studies have provided valuable insight into these processes, which will help motivate generalized models that accurately account for these forces. This project will develop better parameterizations of subgrid processes in Earth's core by incorporating into the similarity and Navier-Stokes-alpha models, knowledge of the structure of the small-scale fields. The project will involve a combination of numerical simulation and theoretical analysis employing not only simplified models that isolate physical processes and analytical issues, but also realistic geodynamo models. The research will be undertaken by a group of mathematicians and geoscientists from US institutions and from abroad under the supervision of a management group. The project will foster interactions between members of the dynamo collective, and it is expected that further collaborations will result from the annual workshops that will be organized and partially supported by the project. It is anticipated that improved parameterization of subgrid processes in rotating magnetoconvection will interest all who wish to study magnetism and dynamos in other planets and in stars. It is believed that many of these people will wish to participate in the planned workshops. An improved numerical model of the geodynamo will be of interest to a second group of geoscientists and mathematicians who seek to quantify the structure, dynamics and history of the interior of our planet.--

EAR-0222205LoperEarth 的发电机负责地磁场，是一个涉及广泛的相互作用尺度、复杂的几何形状和丰富多样的物理过程的地球系统。数值模拟仅解决最大尺度的特征；大多数较小的亚网格尺度过程的参数化仅模拟耗散过程，并且无法模拟影响不同空间尺度之间能量传输的非耗散过程。 该声明的例外是最近开发的相似性模型和纳维-斯托克斯-阿尔法模型。核心动力学受到科里奥利力和洛伦兹力作用的强烈影响，使得场具有各向异性和非局域性。 最近的研究为这些过程提供了宝贵的见解，这将有助于激发准确解释这些力量的广义模型。 该项目将通过将小尺度场结构的知识纳入相似性和纳维斯托克斯阿尔法模型中，开发更好的地核子网格过程参数化。该项目将结合数值模拟和理论分析，不仅采用隔离物理过程和分析问题的简化模型，还采用现实的地球发电机模型。该研究将由来自美国和国外机构的一组数学家和地球科学家在管理小组的监督下进行。 该项目将促进发电机集体成员之间的互动，预计该项目将组织并部分支持的年度研讨会将带来进一步的合作。 预计旋转磁对流中亚网格过程参数化的改进将引起所有希望研究其他行星和恒星中的磁性和发电机的人的兴趣。 相信其中许多人都希望参加计划中的研讨会。改进的地球发电机数值模型将引起第二组地球科学家和数学家的兴趣，他们试图量化地球内部的结构、动力学和历史。