Event study combining magnetospheric and ionospheric perspectives of the substorm current wedge modeling
Event study combining magnetospheric and ionospheric perspectives of the substorm current wedge modeling
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结合磁层和电离层视角的亚暴流楔形模型事件研究
DOI：
10.1002/2014ja020522
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
H. Korth
中科院分区：
文献类型：
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作者：
V. Sergeev;A. Nikolaev;M. Kubyshkina;N. Tsyganenko;H. Singer;J. V. Rodriguez;V. Angelopoulos;R. Nakamura;S. Milan;J. Coxon;B. Anderson;H. Korth
2010年3月17日的亚暴具有前所未有的航天器和仪器覆盖范围，其孤立的性质和明显的阶梯状发展使得双环亚暴电流楔模型（SCW 2L）得到了验证。我们发现一个密切的时空关系的SCW与许多其他必要的签名亚暴活动的磁尾，并证明其方位角定位结构和逐步扩大的磁尾。我们确认，地面SCW诊断使得有可能重建和组织方位角时空亚暴发展模式，其精度优于1小时磁当地时间（MLT）的情况下，中尺度亚暴。基于活动磁层和行星电动力学响应实验（AMPERE）的全球场向电流分布研究表明：（a）与SCW相关的场向电流系统由同时激活的R1和R2型电流组成，（B）它们的净电流具有R1意义，（c）净电流峰值的位置与从中纬度变化推断的SCW边缘位置一致。由于四个GOES和三个亚暴航天器期间事件和大尺度相互作用的时间历史的良好方位角覆盖，我们评估了从磁层和地面中纬度磁性观测组合获得的SCW R1和R2类电流环（使用SCW 2L模型）的强度，并发现净电流与基于AMPERE的估计一致（在2倍以内）。我们还运行了一个自适应磁层模型，并表明，SCW2L模型在预测亚暴偶极期间的磁位形变化方面优于它。
Unprecedented spacecraft and instrumental coverage and the isolated nature and distinct step‐like development of a substorm on 17 March 2010 has allowed validation of the two‐loop substorm current wedge model (SCW2L). We find a close spatiotemporal relationship of the SCW with many other essential signatures of substorm activity in the magnetotail and demonstrate its azimuthally localized structure and stepwise expansion in the magnetotail. We confirm that ground SCW diagnostics makes it possible to reconstruct and organize the azimuthal spatiotemporal substorm development pattern with accuracy better than 1 h magnetic local time (MLT) in the case of medium‐scale substorm. The Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE)‐based study of global field‐aligned current distribution indicates that (a) the SCW‐related field‐aligned current system consists of simultaneously activated R1‐ and R2‐type currents, (b) their net currents have a R1‐sense, and (c) locations of net current peaks are consistent with the SCW edge locations inferred from midlatitude variations. Thanks to good azimuthal coverage of four GOES and three Time History of Events and Macroscale Interactions during Substorms spacecraft, we evaluated the intensities of the SCW R1‐ and R2‐like current loops (using the SCW2L model) obtained from combined magnetospheric and ground midlatitude magnetic observations and found the net currents consistent (within a factor of 2) with the AMPERE‐based estimate. We also ran an adaptive magnetospheric model and show that SCW2L model outperforms it in predicting the magnetic configuration changes during substorm dipolarizations.