•	Conjugate IS radar scans and space-borne imagery revealed an interaction between F-region plasma patches and ion upflow along the polar cap boundary.
	•	Plasma patches found to modulate upflowing number flux at sites of nightside magnetic reconnection.
	•	Unlike upflows in the main oval, polar boundary upflows have no causative relationship with ion or electron temperature, indicating a mechanism other than thermal expansion.
	Semeter, J., C.J. Heinselman, J.P Thayer, R.A. Doe, and H.U. Frey, Ion upflow enhanced by drifting F-region plasma structure on the nightside polar cap boundary, Geophys. Res. Lett., accepted August, 2003.