Field-aligned currents during northward IMF

Studies of field-aligned currents have advanced a great deal during the International Magnetospheric Study (IMS) period. However, there still remain many areas that need further examination. One of them is examined here and involves a case study of field-aligned currents and ionospheric currents during a period of strong northward interplanetary magnetic field (IMF). The present results provide the first evidence for reversed two-cell convection-type horizontal current at high latitudes in the ionosphere which is associated with large-scale field-aligned currents. These field-aligned currents are located poleward of region 1 currents and have the opposite flow directions of region 1 currents. 13 references