GEM Systems Science: Creating and Analyzing an Earth Index Collection

地球空间环境模拟方案是一个基础广泛、由社区发起的关于地球磁层物理以及磁层与大气和太阳风的耦合的研究方案。GEM的工作是通过一系列活动和焦点小组完成的，这些活动和重点小组解决具体问题，从而建立具有预测能力的全球地球空间环流模式(GGCM)。该项目将有助于实现关于了解地球磁层-电离层系统对太阳风的全球反应以及太阳风如何耦合到磁层的这一目标的基本成果。磁层对驱动的反应以及太阳风的驱动比通常认为的要复杂得多，也比目前的模型能够捕捉或解释的要复杂得多。这项调查将进行全面的统计分析，以探索这些复杂性。所创建的数据集和分析结果将通过即将创建的新的“地球指数汇编”网页进行传播。这项调查将采用系统科学的方法，分析多次测量的磁层对整个太阳风数据集的反应。它将收集和创建大量与时间相关的指数，每个指数都是磁层-电离层系统的不同衡量标准。“指数”将是对系统中的电流、等离子体、高能粒子、波、形态和能量流的测量。这些与时间相关的指数集合将被放在一起，形成一个与时间相关的“地球指数集合”。将使用典型相关分析来确定和探索多变量地球指数收集和多变量太阳风数据集之间的相关模式。对于地球指数收集对太阳风的主要反应模式，将确定和定义一个与时间相关的“集体指数”，并将定义驱动该主要模式的普遍耦合函数。将对地球对太阳风的反应的次要全球模式进行识别、编目和调查，并将确定驱动次要模式的太阳风的性质(次要耦合函数)。将尝试将二次耦合功能与物理机制联系起来，例如粘性相互作用、白天重联线位置的变化以及磁层形态的变化。通过对次级反应模式的分析，将确定地球指数集合中的“部门”，并对构成每个部门的指数进行编目。探索抑制和混淆多变量太阳风数据集由于其变量与地球测量值相关，因此将确定因果关联和非因果关联。最后，将使用传统的数据分析方法来阐明磁层对太阳风的反应的部门和全球模式。

The Geospace Environment Modeling (GEM) Program is a broad-based, community-initiated research program on the physics of the Earth's magnetosphere and the coupling of the magnetosphere to the atmosphere and to the solar wind. The work of GEM is accomplished in a series of campaigns and focus groups that solve specific problems leading to the construction of a global Geospace General Circulation Model (GGCM) with predictive capability. This project will contribute essential results to this goal pertaining to understanding the global reaction of the Earth's magnetosphere-ionosphere system to the solar wind and how the solar wind couples to the magnetosphere. The reaction of the magnetosphere to driving as well as the driving by the solar wind are more complex than commonly thought and than current models can capture or explain. This Investigation will perform a comprehensive statistical analysis to explore those complexities. The data sets created and the findings of the analysis will be disseminated via a new "Earth Index Collection" webpage to be created. Tutorials, examples, and research suggestions will also be made available via the webpage.This Investigation will take a systems-science approach, analyzing the reaction of the multiply measured magnetosphere to the full solar-wind data set. It will collect and create a large number of time-dependent indices, each one being a different measure of the magnetosphere-ionosphere system. The "indices" will be measures of the currents, plasmas, energetic particles, waves, morphology, and energy flow in the system. The collection of time-dependent indices will be put together to form a time-dependent "Earth Index Collection" of measurements. Canonical correlation analysis will be used to identify and explore correlation patterns between the multivariable Earth index collection and the multivariable solar-wind data set. For the primary mode of reaction of the Earth index collection to the solar wind, a time-dependent "collective index" will be identified and defined and the universal coupling function that drives that primary mode will be defined. Secondary global modes of the reaction of the Earth to the solar wind will be identified, cataloged, and investigated and the properties of the solar wind (the secondary coupling functions) that drive the secondary modes will be identified. Attempts will be made to connect the secondary coupling functions with physical mechanisms such as the viscous interaction, changes in the location of the dayside reconnection line, and changes in the morphology of the magnetosphere. By analysis of the secondary modes of reaction, the "sectors" of the Earth index collection will be identified and the indices that comprise each sector will be cataloged. Exploring suppression and confounding in the multivariable solar-wind data set as its variables correlate with the Earth measurements, causal correlations versus non-causal correlations will be identified. Finally, traditional data-analysis methods will be used to elucidate the sectors and the global modes of reaction of the magnetosphere to the solar wind.