Substorms and polar cap convection: the 10 January 2004 interplanetary CME case
Substorms and polar cap convection: the 10 January 2004 interplanetary CME case
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DOI：
10.5194/angeo-30-67-2012
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发表时间：
2012-01
影响因子：
1.9
通讯作者：
Y. Andalsvik;P. Sandholt;C. Farrugia
中科院分区：
文献类型：
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作者：
Y. Andalsvik;P. Sandholt;C. Farrugia
摘要。Dungey细胞等离子体对流的膨胀-收缩模型有两个不同的对流源，即磁层顶重联和磁尾重联。夜侧光源的时空结构还没有被很好地理解。在这项研究中，我们将确定在稳定的行星际条件下，亚暴活动期间冬季极帽对流结构的时间变化。亚暴活动（电喷流和粒子降水）是由地面卫星DMSP F15在黄昏至午夜前扇区监测的。利用Svalbard - Scandinavia - Russia地区IMAGE地面磁力计链的广泛纬度覆盖，监测与极帽对流和亚风暴电喷相关的磁偏转。通过superdam雷达对极帽对流的直接观测和DMSP F13航天器沿黄昏-黎明子午线穿越极帽时的交叉轨道离子漂移观测，这些数据得到了增强。我们研究的时间间隔的特点是，在地球通过行星际CME （ICME）期间，磁层-电离层系统（EKL = 4.0-4.5 mV m - 1；跨极帽势（CPCP）， Φ (Boyle) = 115 kV）的中等、稳定的强迫，选择了磁场连续指向西南（Bz）的4小时间隔
Abstract. The expansion-contraction model of Dungey cell plasma convection has two different convection sources, i.e. reconnections at the magnetopause and in the magnetotail. The spatial-temporal structure of the nightside source is not yet well understood. In this study we shall identify temporal variations in the winter polar cap convection structure during substorm activity under steady interplanetary conditions. Substorm activity (electrojets and particle precipitations) is monitored by excellent ground-satellite DMSP F15 conjunctions in the dusk-premidnight sector. We take advantage of the wide latitudinal coverage of the IMAGE chain of ground magnetometers in Svalbard – Scandinavia – Russia for the purpose of monitoring magnetic deflections associated with polar cap convection and substorm electrojets. These are augmented by direct observations of polar cap convection derived from SuperDARN radars and cross-track ion drift observations during traversals of polar cap along the dusk-dawn meridian by spacecraft DMSP F13. The interval we study is characterized by moderate, stable forcing of the magnetosphere-ionosphere system (EKL = 4.0–4.5 mV m−1; cross polar cap potential (CPCP), Φ (Boyle) = 115 kV) during Earth passage of an interplanetary CME (ICME), choosing an 4-h interval where the magnetic field pointed continuously south-west (Bz