Challenges Handling Magnetospheric and Ionospheric Signals in Internal Geomagnetic Field Modelling
Challenges Handling Magnetospheric and Ionospheric Signals in Internal Geomagnetic Field Modelling
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DOI：
10.1007/s11214-016-0285-9
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发表时间：
2017-03
影响因子：
10.3
通讯作者：
C. Finlay;V. Lesur;E. Thébault;F. Vervelidou;A. Morschhauser;R. Shore
中科院分区：
文献类型：
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作者：
C. Finlay;V. Lesur;E. Thébault;F. Vervelidou;A. Morschhauser;R. Shore
由低地球轨道卫星（如Swarm和CHAMP）以及地面观测站收集的地球磁场测量结果主要来自地球内部。然而，这些测量也包含了电离层和磁层中变化更快的电流系统的重要贡献。为了充分利用磁测数据来探测地球内部的物理特性和动力学，必须建立适当处理外部源及其相关感应信号的场模型。在这里，我们回顾目前用于构建模型的内部场的方法，专注于处理磁层和电离层信号的技术。这些技术的缺点往往限制了内部场模型的质量以及空间和时间分辨率。我们记录的困难，在使用跟踪跟踪分析，以表征磁层场波动，内部场模型的差异，导致从安静时间电离层场的替代治疗，并与快速变化，但空间相关的挑战，极地帽电流系统的磁签名。可能的战略，以改善内部领域的模型进行了讨论，其中许多更详细地描述在本卷的其他地方。
Measurements of the Earth’s magnetic field collected by low-Earth-orbit satellites such asSwarmand CHAMP, as well as at ground observatories, are dominated by sources in the Earth’s interior. However these measurements also contain significant contributions from more rapidly-varying current systems in the ionosphere and magnetosphere. In order to fully exploit magnetic data to probe the physical properties and dynamics of the Earth’s interior, field models with suitable treatments of external sources, and their associated induced signals, are essential. Here we review the methods presently used to construct models of the internal field, focusing on techniques to handle magnetospheric and ionospheric signals. Shortcomings of these techniques often limit the quality, as well as spatial and temporal resolution, of internal field models. We document difficulties in using track-by-track analysis to characterize magnetospheric field fluctuations, differences in internal field models that result from alternative treatments of the quiet-time ionospheric field, and challenges associated with rapidly changing, but spatially correlated, magnetic signatures of polar cap current systems. Possible strategies for improving internal field models are discussed, many of which are described in more detail elsewhere in this volume.