European Geosciences Union, Annales Geophysicae, 10(16), p. 1190-1199, 1998
DOI: 10.1007/s00585-998-1190-7
European Geosciences Union, Annales Geophysicae, 10(16), p. 1190
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Since the middle of 1995, an HF Doppler sounder has been running almost continuously in northern Norway, with the receiver at Ramfjordmoen and the transmitter at Seljelvnes. Concurrent operation of the EISCAT UHF radar in common programme (CP-1) mode has made it possible to study the ionospheric signature of a magnetospheric ULF wave. These are the first results of such wave signatures observed simultaneously in both instruments. It has been demonstrated that the observed Doppler signature was mainly due to the vertical bulk motion of the ionosphere caused by the electric field perturbation of the ULF wave and the first direct observational confirmation of a numerical simulation has been achieved. The wave, which was Alfvénic nature, was detected by the instruments 8° equatorward of the broad resonance region. The implications for the deduced wave modes in the ionosphere and the mechanism producing the HF Doppler variations are discussed. ; Royal Society for funding the initial construction of the DOPE project and the Particle Physics and Astronomy Research Council for support during the work presented in this paper ; Peer-reviewed ; Publisher Version ; 8th EISCAT Scientific Workshop, UNIV LEICESTER, LEICESTER, ENGLAND