CAREER: Modeling and Estimation of Dynamic High-latitude Ionospheric Loss and Transport Processes

研究者将通过协同使用二维和三维模型以及涉及非相干散射雷达和光学光谱仪数据的新估计方案来研究电离层源动力学的细节。高纬度电离层等离子体密度和结构在地面电离层-热层-磁层（ITM）耦合系统中起着至关重要的作用。实验和模型研究已经令人信服地证明了电离层重离子在各个磁层区域的存在，并且这些重离子明显地影响了ITM系统对太阳风强迫的响应。电离层源及其动力学在调节离子流出过程中起着重要作用。这项研究将直接解决目前观测高纬度电离层等离子体组成能力的几个空白，以及我们对加热事件和相关瞬态的时间动态性质的理解，这些瞬态控制着组成、电离层上升以及中尺度和小尺度电离层等离子体密度结构的产生。具体的科学目标将是提供详细的数据模型分析，以确定：(1)风暴时电离层分子离子流出源的位置和强度；(2)现实极光电流系统中分子离子重组、电流闭合耗尽和离子上流对等离子体损失的贡献；(3)电离层主要损失和输运过程运行的时间尺度，包括高动态情况下电磁感应的影响；(5)低空上升流的时间依赖性，包括上升流起始瞬态和向高空有限传播时间，以及某些类型的波粒相互作用对上升流的可能影响。领导该项目的早期职业科学家将重点支持ERAU工程物理学的新博士课程，包括资助学生完成硕士和博士论文，并改进PI的硕士和博士课程，包括当代空间物理学研究主题和学生研究项目。支持本科生研究的努力将通过资助暑期项目、独立研究和为高素质学生开发新的、为期一年的毕业论文选项来继续。该项目将支持并进一步发展新的和现有的学术课程，主要面向本科生和研究生的参与，并特别打算与全校范围内的学生研究计划IGNITE合作。研究成果将通过及时出版提供，预计许多贡献将产生学生撰写的论文。所进行的研究将代表与欧洲和南美机构的国际合作，支持工作的某些方面。为解决上述科学目标而开发的方法（即模型和估计方案）可能会成为社区在其他相关研究中使用的有用工具。

The investigator will study the details of ionospheric source dynamics through synergistic use of two- and three- dimensional models and new estimation schemes involving both incoherent scatter radar and optical spectrograph data. High-latitude ionospheric plasma density and structure play a critical role in the coupled terrestrial ionosphere-thermosphere-magnetosphere (ITM) system. Experimental and modeling studies have convincingly demonstrated the presence of heavy ions of ionospheric origin in various magnetospheric regions, and that these heavy ions appreciably affect response of the ITM system to solar wind forcing. The ionospheric source and its dynamics play a substantial role in modulating this ion outflow process. This research will directly address several gaps in the current ability to observe the composition of the high-latitude ionospheric plasma and our understanding of the temporally dynamic nature of heating events and associated transients governing composition, ionospheric upflows, and the generation of mesoscale and small-scale ionospheric plasma density structures. Specific science objectives will be to provide detailed data-model analyses to determine the: (1) Location and intensity of storm-time ionospheric sources for molecular ion outflow (2) Contributions of molecular ion recombination, current closure depletion, and ion upflows to plasma loss in realistic auroral current systems (3) Time scales on which major ionospheric loss and transport processes operate, including the effects of electromagnetic induction in highly dynamic situations (4) Effects of three-dimensional current system geometries on ionospheric transport and loss, and the role of these processes in the development of smaller-scale irregularities (5) Temporal dependence of low altitude upflow, including transients in upflow initiation and finite propagation times to higher altitudes, and possible influence of some types of wave-particle interactions on upflow. The early career scientist leading this project will focus on supporting a new PhD program in Engineering Physics at ERAU, including funding of students completing MS and PhD theses, and refinement of the PI's MS and PhD courses to include contemporary space physics research topics where appropriate, and student research projects. Efforts to support undergraduate research will continue through funded summer projects, independent studies, and development of a new, year-long senior thesis option for highly qualified students. This project will support and further develop new and existing academic programs, is heavily pitched toward both undergraduate and graduate student involvement, and is specifically intended to work in concert with the university-wide student research initiative IGNITE. Research results will be made available through prompt publication, and it is anticipated that many of the contributions will yield student-authored papers. The research undertaken will represent an international collaboration with both European and South American institutions supporting some aspects of the work. Methods developed for addressing the science goals above (i.e. models and estimation schemes), will likely serve as useful tools for the community to use in other related studies.