Variability of dayside convection and motions of the cusp/cleft aurora

Lockwood, M. ORCID: https://orcid.org/0000-0002-7397-2172, Moen, J., Cowley, S. W. H., Farmer, A. D., Løvhaug, U. P., Lühr, H. and Davda, V. N. (1993) Variability of dayside convection and motions of the cusp/cleft aurora. Geophysical Research Letters, 20 (11). pp. 1011-1014. ISSN 0094-8276 doi: 10.1029/93GL00846

Abstract/Summary

We present measurements of the ionospheric plasma flow over the range of invariant latitudes 71–76°, observed at 10-second resolution using both the EISCAT radars, with simultaneous observations of the 630 nm cusp/cleft aurora made by a meridian-scanning photometer at Ny Ålesund, Svalbard. A major increase in the trans-auroral voltage from 5 to 40 kV (associated with sunward convection in the early afternoon sector) is found to follow a southward motion of the aurora and coincide with the onset of regular transient auroral breakup events. It is shown that these observations are consistent with recent theoretical work on how ionospheric flows are excited by time-dependent reconnection at the dayside magnetopause.