A survey of magnetopause FTEs and associated flow bursts in the polar ionosphere

D. A. Neudegg (1) , S. W. H. Cowley (1) , S. E. Milan (1) , T. K. Yeoman (1) , M. Lester (1) , G. Provan (1) , G. Haerendel (2) , W. Baumjohann (2) , B. Nikutowski (3) , J. Büchner (3) , U. Auster (4) , K.-H. Fornacon (4) , E. Georgescu (2, 5)

1 Department of Physics and Astronomy [Leicester]
2 MPE - Max-Planck-Institut für Extraterrestrische Physik
3 MPI Aeronomie - Max-Planck-Institut für Aeronomie
4 Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig]
5 ISS - Institute of Space Science [Bucharest-Măgurele]

Using the Equator-S spacecraft and SuperDARN HF radars an extensive survey of bursty reconnection at the magnetopause and associated flows in the polar ionosphere has been conducted. Flux transfer event (FTE) signatures were identified in the Equator-S magnetometer data during periods of magnetopause contact in January and February 1998. Assuming the effects of the FTEs propagate to the polar ionosphere as geomagnetic field-aligned-currents and associated Alfvén-waves, appropriate field mappings to the fields-of-view of SuperDARN radars were performed. The radars observed discrete ionospheric flow channel events (FCEs) of the type previously assumed to be related to pulse reconnection. Such FCEs were associated with \sim80% of the FTEs and the two signatures are shown to be statistically associated with greater than 99% confidence. Exemplary case studies highlight the nature of the ionospheric flows and their relation to the high latitude convection pattern, the association methodology, and the problems caused by instrument limitations.

Domaines: Océan, Atmosphère; Sciences de la Terre

D. A. Neudegg, S. W. H. Cowley, S. E. Milan, T. K. Yeoman, M. Lester, et al.. A survey of magnetopause FTEs and associated flow bursts in the polar ionosphere. Annales Geophysicae, 2000, 18 (4), pp.416-435. ⟨hal-00316618⟩