Auroral Signatures of Ballooning Mode Near Substorm Onset: Open Geospace General Circulation Model Simulations
Auroral Signatures of Ballooning Mode Near Substorm Onset: Open Geospace General Circulation Model Simulations
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亚暴爆发附近气球模式的极光特征：开放地球空间大气环流模型模拟
DOI：
10.1029/2011gm001200
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
G. Siscoe
中科院分区：
文献类型：
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作者：
J. Raeder;P. Zhu;Y. Ge;G. Siscoe
极光现象其他行星地球物理Mon © 2012. American 10.1029/2011 GM我们介绍了2007年3月23日THEMIS“第一光”亚暴的开放地球空间环流模式模拟结果。我们调查之间的关系气球模式的尾巴和极光的“珠”。尾部气球状结构的磁图显示了一个非常类似极光珠子的电离层特征。尾部的气球性质与观测结果的密切匹配，特别是方位角波长约为0.5 RE，以及模拟中映射的气球结构与观测到的极光珠的密切相似性，提供了证据表明珠是尾部气球模式的特征。由于极光比尾巴更容易在全球范围内观察到，这一结果允许使用极光观测研究气球与亚暴阶段的关系。从模拟中，我们没有发现气球模式和膨胀相开始之间的直接联系。然而，位于膨胀和撕裂之间的其他不稳定性可能起着重要的触发作用。
Auroral Phenomen Other Planets Geophysical Mon © 2012. American 10.1029/2011GM We present results from Open Geospace General Circulation Model simulations of the 23 March 2007 THEMIS “first light” substorm. We investigate the relation between ballooning modes in the tail and auroral “beads.”Magnetic mapping of the ballooning structures in the tail shows an ionosphere signature that closely resembles auroral beads. The close match of the ballooning properties in the tail with observations, in particular an azimuthal wavelength of ~0.5 RE, and the close resemblance of the mapped ballooning structures in the simulation with observed auroral beads provides evidence that beads are a signature of tail ballooning modes. Since the aurora is much easier observed globally than the tail, this result allows studying the relation of ballooning to the substorm phases using auroral observations. From the simulation, we find no direct connection between the ballooning mode and expansion phase onset. However, other instabilities that lie somewhere between ballooning and tearing may play an important role as trigger.