Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.490 IF 1.490
  • IF 5-year value: 1.445 IF 5-year
    1.445
  • CiteScore value: 2.9 CiteScore
    2.9
  • SNIP value: 0.789 SNIP 0.789
  • IPP value: 1.48 IPP 1.48
  • SJR value: 0.74 SJR 0.74
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 88 Scimago H
    index 88
  • h5-index value: 21 h5-index 21
Volume 17, issue 9
Ann. Geophys., 17, 1166–1171, 1999
https://doi.org/10.1007/s00585-999-1166-2
© European Geosciences Union 1999
Ann. Geophys., 17, 1166–1171, 1999
https://doi.org/10.1007/s00585-999-1166-2
© European Geosciences Union 1999

  30 Sep 1999

30 Sep 1999

The ionospheric signature of transient dayside reconnection and the associated pulsed convection return flow

S. E. Milan1, M. Lester1, R. A. Greenwald2, and G. Sofko3 S. E. Milan et al.
  • 1Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
  • 2Johns Hopkins University, Applied Physics Laboratory, Maryland, USA
  • 3University of Saskatchewan, Saskatchewan, Canada

Abstract. Three SuperDARN coherent HF radars are employed to investigate the excitation of convection in the dayside high-latitude ionosphere in response to transient reconnection occurring in the cusp region. This study demonstrates the existence of transient antisunward-propagating backscatter features at the expected location of the ionospheric footprint of the cusp region, which have a repetition rate near 10 min. These are interpreted as the ionospheric signature of flux transfer events. Moreover, transient sunward-propagating regions of backscatter are observed in the convection return flow regions of both the pre- and post-noon sectors. These patches are observed to propagate towards the noon sector from at least as far around the auroral zone as 07 MLT in the pre-noon sector and 17 MLT in the post-noon sector, travelling with a velocity of approximately 1.5 to 2 km s-1. These return flow patches have a repetition rate similar to that of the transient features observed at local noon. While providing supporting evidence for the impulsive nature of convection flow, the observation of sunward-propagating features in the return flow region is not consistent with current conceptual models of the excitation of convection.

Key words. Ionosphere (plasma convection) · Magnetospheric physics (magnetopause · cusp · and boundary layers; magnetosphere-ionosphere interactions)

Publications Copernicus
Download
Citation