Magnetic Impulses and Associated Optical Signatures in the Dayside Aurora.

We present five magnetic impulse events observed at South Pole and in the magnetically conjugate area at Iqaluit. The magnetic signatures recorded during these events appear to be similar to those discussed by several authors as possible ionospheric signatures of sporadic dayside reconnection via the flux transfer process. Coordinated ground-based image-intensified all sky camera data were acquired at South Pole during the events. The optical data show that prior to the onset of each of the events the dayside cusp aurora is several degrees poleward of the station, signifying the event initiation on closed field lines.