【作者】 J.R.Kan； 孙炜；

【Author】 J.R.Kan W.Sun~①(Geophysical Institute,University of Alaska,Fairbanks)

【机构】 美国阿拉斯加大学地球物理研究所； 中国科学院地球物理研究所；

【摘要】 由于亚暴期间磁层对流突然增强而激发的阿尔文波,在非均匀的电离层和磁层之间的连续反射而改变电离层的电场和电流.本文根据二维的模式,模拟了西向涌浪和Pi 2脉动的形成过程.更多还原

【Abstract】 The westward traveling surge and the Pi 2 pulsations are simulated as a consequence of an enhanced magnctospheric convection in a model of magnetosphere-ionosphere coupling.The coupling is characterized by the bouncing of Alfven waves launched by the enhanced convection.The reflection of Alfven waves from the ionosphere is treated in which the height-integrated conductivity is allowed to be highly nonuniform and fully anisotropic.The reflection of Alfven waves from the magnetosphere is characterized by the coefficient R_m,depending on whether the field lines are open or closed.On open field lines the reflection coefficient from the magnetopause is given by R_m≈-1.On closed field lines the reflection coefficient is given by(1)R_m≈+1 in the near-earth plasma sheet and(2)-1≤R_m≤+1 in the low-latitude boundary layer and the distant plasma sheet.The conductivity in the model is selfconsistently enhanced with increasing upward field-aligned current density.The results of the simulation,including the convection pattern,the electro jets,the field-aligned current,the conductivity enhancement,the oscillation of the westward electrojet,and the average speed of the westward surge are in reasonable agreement with the features of the westward traveling surge and the Pi 2 pulsations observed during substorms.更多还原