GEM: Self-consistent Modeling of the Near-Earth Magnetosphere with Induced Electric Fields

该项目旨在实现美国国家科学基金会地球空间环境建模方案的中心目标，即支持对地球空间的动力和结构特性进行基础研究，从而建立一个具有预测能力的全球地球空间大气环流模型。未来GGCM发展的一个重要部分，以及新的“近地磁层：等离子体，场和耦合”焦点小组的建模重点，是创建内/中磁层模块，忠实地描述等离子体传输的物理学，以及等离子体和场之间的自洽相互作用。该项目将最终形成这样一个单元;它将开发一个等离子体和场的现实的三维近地磁层模型，其中将包括自洽磁场和感应电场、地球偶极子倾斜和在距地球10个地球半径处扩展到等离子体片的边界。数值模型将通过与观测场和等离子体数据的比较进行验证，包括原位数据/模型比较和使用模型场的相空间密度分析。这些比较将阐明各种模型特征对所产生的磁层结构和动力学的影响，也将限制模型参数。该模型将接受各种磁场和等离子体边界条件（包括来自全球数值MHD（磁流体动力学）模型），因此将准备集成到GGCM中。这项研究还将导致在选定的事件期间绘制计算的、自洽的、磁层内等离子体分布、磁场和电场以及等离子体波的全球地图。这些地图将提供给社区用于其他观测和理论空间物理应用。该项目的大部分资金将用于年轻科学家（主要研究员（PI）），以及洛斯阿拉莫斯国家实验室（LANL）的博士后和暑期学生。最终，该项目通过对具有预测能力的GGCM做出贡献，将对国家空间气象计划具有价值。

This project is directed towards the central goal of the NSF Geospace Environment Modeling (GEM) Program, which is to support basic research into the dynamical and structural properties of geospace, leading to the construction of a global Geospace General Circulation Model (GGCM) with predictive capability. An important part in the development of the future GGCM, and the modeling emphasis of the new "Near-Earth Magnetosphere: Plasma, Fields and Coupling" Focus Group, is the creation of inner/middle magnetosphere module(s) that faithfully describe the physics of the plasma transport, as well as the self-consistent interaction between plasma and fields. This project will lead to such a module; it will develop a realistic, 3-D, near-Earth, magnetosphere model of plasma and fields that will include self-consistent magnetic and induced electric fields, the Earth's dipole tilt and an expanded boundary into the plasma sheet at 10 Earth radii from Earth. The numerical model will be verified by comparisons with observed field and plasma data, including in situ data/model comparison and phase space density analysis using model fields. These comparisons will elucidate the influence of the various model features on the resulting magnetospheric structure and dynamics and will also constrain model parameters. The model will accept various magnetic field and plasma boundary conditions (including from global numerical MHD (magnetohydrodynamics) models), and will thus be ready for integration into a GGCM. The research will also result in global maps of computed, self-consistent, inner-magnetospheric plasma distributions, magnetic and electric fields and plasma waves during selected events. These maps will be made available to the community for use in other observational and theoretical space physics applications. A substantial portion of the funding for this project will be used young scientist (the Principal Investigator (PI)), as well as a postdoc and a summer student at Los Alamos National Laboratory (LANL). Ultimately, the project, by contributing to a GGCM with predictive capabilities, will be of value to the National Space Weather Program.