THE PULSATING CUSP

Recent observations at the magnetopause and of the high‐latitude ionosphere, suggest that the cusp may be pulsed in nature. Specifically ground‐based observations in the dayside auroral oval reveal transient optical features accompanied by bursts of enhanced plasma flow. Also, recent interpretation has shown cusp satellite data to be consistent with a burst of enhanced reconnection. In this paper we use these observations to produce a scenario in which both the satellite and ground‐based observations can be fitted. The scenario we develop is based on the flux transfer event (FTE) models of Southwood et al. and Scholer and shows that the signatures, at both low and high altitudes, can be interpreted in terms of FTEs. © 1990 by the Chinese Geophysical Society