A global magnetosphere‐ionosphere coupling model of substorms
A global magnetosphere‐ionosphere coupling model of substorms
复制标题
亚暴的全球磁层-电离层耦合模型
DOI：
10.1029/93ja01168
复制
发表时间：
1993
影响因子：
--
通讯作者：
J. Kan
中科院分区：
文献类型：
--
作者：
J. Kan
在观测综合和理论建模的基础上提出了亚暴的全球模型。由于本模型的理论基础是磁层-电离层耦合（MIC）过程，因此称为亚暴MIC模型。与广受欢迎的近地中性线 (NENL) 亚暴模型相反，MIC 模型中的亚暴可能在近地等离子体片中没有形成新的 X 线的情况下发生。在增强的日侧重新连接之后，电离层使开放场线上的太阳风和封闭场线上的等离子体片超载。太阳风通过在开放场线上的发电机作用提供更多驱动能量来应对过载。等离子体片通过自身塌陷来响应过载，即使其场结构极化以形成亚暴电流楔。膨胀阶段的爆炸强化是通过释放存储在等离子体片的闭合磁力线上的磁能来驱动的。储存的能量由亚暴电流楔中的正反馈驱动的卸载不稳定性释放。
A global model of substorms is proposed on the basis of observational synthesis and theoretical modeling. Since the theoretical basis of the present model is the magnetosphere-ionosphere coupling (MIC) process, it will be called the MIC model of substorms. Substorms can occur in the MIC model without a new X line formed in the near-Earth plasma sheet, in contrast to the highly popular near-Earth neutral line (NENL) model of substorms. Following enhanced dayside reconnection, the ionosphere overloads both the solar wind on open field lines and the plasma sheet on closed field lines. The solar wind responds to the overload by providing more driven energy from the dynamo action on open field lines. The plasma sheet responds to the overload by collapsing itself, i.e., dipolarizing its field configuration to form the substorm current wedge. The explosive intensification during the expansion phase is powered by releasing the magnetic energy stored on closed field lines in the plasma sheet. The stored energy is released by the unloading instability driven by a positive feedback in the substorm current wedge.