Vertical motions of the midlatitude F2 layer during magnetospheric substorms.

Use of ground-based ionosonde records from midlatitude stations during winter nights to study vertical motions of the F2 layer associated with magnetospheric substorms. The results show that during substorms the F2 layer is lifted upward in the premidnight sector and pushed downward in the postmidnight sector. These motions are interpreted in terms of E x B drifts, the electric field being eastward on the eveningside and westward on the morningside. The results emphasize the importance of substorm effects on the midlatitude F region and the potential of ground-based hf sounding techniques in studying magnetospheric substorms.