Transpolar arcs observed simultaneously in both hemispheres
Transpolar arcs observed simultaneously in both hemispheres
复制标题
DOI：
10.1002/2016ja023830
复制
发表时间：
2017-06
期刊：
影响因子：
--
通讯作者：
J. Carter;S. Milan;R. Fear;M. Walach;Z. A. Harrison;L. Paxton;B. Hubert
中科院分区：
文献类型：
--
作者：
J. Carter;S. Milan;R. Fear;M. Walach;Z. A. Harrison;L. Paxton;B. Hubert
2005年8月31日观测到两个共存的跨极弧。我们跟踪弧的形成和运动在北方和南半球，使用两个独立的卫星（成像仪磁层顶极光全球探索和国防气象卫星计划卫星）的数据。这些观测得到了来自超级双极光雷达网络的补充地面电离层对流数据的支持。这两条弧是在行星际磁场向北的时期形成的。随着行星际磁场BY分量方向由负变正，晨间弧穿过极帽到达北方半球的晨间弧。在同一时期的南半球，黄昏弧穿过极冠到达黎明。一个复杂的磁场线拓扑结构，导致两个舌头的封闭的磁力线突出到否则开放的极帽共存。我们讨论了这些意见的磁共轭和跨极弧形成的模型。
Two coexisting transpolar arcs are observed on 31 August 2005. We track the formation and motion of the arcs in both the Northern and Southern Hemispheres, using data from two independent satellites (Imager for Magnetopause to Aurora Global Exploration and a Defence Meteorological Satellite Program satellite). The observations are supported by supplementary ground‐based ionospheric convection data from the Super Dual Auroral Radar Network. The two arcs form during a period of northward interplanetary magnetic field. Following a change in the direction of the interplanetary magnetic field BY component from negative to positive, the dawnside arc traverses the polar cap to the duskside in the Northern Hemisphere. Over the same time period and in the Southern Hemisphere, the duskside arc traverses the polar cap to the dawnside. A complex magnetic field line topology resulting in the coexistence of two tongues of closed field lines protruding into the otherwise open polar cap is implied. We discuss these observations in terms of magnetic conjugacy and a model of transpolar arcs formation.