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

该项目是针对NSF地球空间环境建模(GEM)计划的中心目标，该计划旨在支持地球空间动力学和结构特性的基础研究，从而建立一个具有预测能力的全球地球空间大气环流模式(GGCM)。未来GGCM发展的一个重要部分，也是新的“近地磁层：等离子体、场和耦合”焦点组的建模重点，是建立内/中磁层模块(S)，它忠实地描述了等离子体输运的物理以及等离子体与场之间的自洽相互作用。该项目将产生这样一个模块；它将开发一个现实的三维近地磁层等离子体和磁场模型，其中将包括自洽磁场和感应电场、地球偶极倾斜和在距地球10个地球半径的等离子体片中扩展的边界。数值模型将通过与观测场和等离子体数据的比较来验证，包括现场数据/模型比较和利用模型场进行相空间密度分析。这些比较将阐明各种模型特征对由此产生的磁层结构和动力学的影响，并将限制模型参数。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)模型)，因此将准备好集成到GGCM中。这项研究还将产生选定事件期间计算的、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。这些地图将向社区提供，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青年科学家(首席研究员(PI))，以及洛斯阿拉莫斯国家实验室(LANL)的一名博士后和一名暑期学生。最终，该项目通过对具有预测能力的GGCM做出贡献，将对国家空间天气计划产生价值。

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.