Convective response to a transient increase in dayside reconnection

Measurements with five of the northern hemisphere Super Dual Auroral Radar Network (SuperDARN) radars have yielded a detailed temporal and spatial vie w of the evolution of a dayside convection enhancement, which we associate with a transient increase in dayside reconnection. The convection enhanceme nt was located in and immediately poleward of the ionospheric footprint of the cusp. During the enhancement, both the cusp and the region of enhanced flow shifted equatorward by similar to 2 degrees. As the flow enhancement d iminished, the cusp footprint moved poleward to its original position. The entire event had a duration of similar to 18 min and was associated with a transient 29 kV increase in the cross polar cap potential. We estimate that similar to 3.2 x 10(7) Wb of magnetic flux was opened at the dayside magne topause during the most active 12 min of this event. The length of the reco nnection line on the dayside magnetopause is estimated to have reached 19,0 00 km. The characteristics of the dayside ionospheric response are very sim ilar to those predicted by Cowley nod Lockwood [1992] in their expanding an d contracting polar cap model. These are the first observations that have p rovided an extended spatial and temporal view of the responses of dayside c onvection and the cusp to a transient reconnection event.