University of Leicester
Browse

Simultaneous observations of traveling convection vortices: Ionosphere-thermosphere coupling

Download (6.93 MB)
journal contribution
posted on 2017-08-22, 15:33 authored by Hyomin Kim, Marc R. Lessard, Sarah L. Jones, Kristina A. Lynch, Philip A. Fernandes, Anasuya L. Aruliah, Mark J. Engebretson, Jøran I. Moen, Kjellmar Oksavik, Alexander G. Yahnin, Timothy K. Yeoman
We present simultaneous observations of magnetosphere-ionosphere-thermosphere coupling over Svalbard during a traveling convection vortex (TCV) event. Various spaceborne and ground-based instruments made coordinated measurements, including magnetometers, particle detectors, an all-sky camera, European Incoherent Scatter (EISCAT) Svalbard Radar, Super Dual Auroral Radar Network (SuperDARN), and SCANning Doppler Imager (SCANDI). The instruments recorded TCVs associated with a sudden change in solar wind dynamic pressure. The data display typical features of TCVs including vortical ionospheric convection patterns seen by the ground magnetometers and SuperDARN radars and auroral precipitation near the cusp observed by the all-sky camera. Simultaneously, electron and ion temperature enhancements with corresponding density increase from soft precipitation are also observed by the EISCAT Svalbard Radar. The ground magnetometers also detected electromagnetic ion cyclotron waves at the approximate time of the TCV arrival. This implies that they were generated by a temperature anisotropy resulting from a compression on the dayside magnetosphere. SCANDI data show a divergence in thermospheric winds during the TCVs, presumably due to thermospheric heating associated with the current closure linked to a field-aligned current system generated by the TCVs. We conclude that solar wind pressure impulse-related transient phenomena can affect even the upper atmospheric dynamics via current systems established by a magnetosphere-ionosphere-thermosphere coupling process.

History

Citation

Journal of Geophysical Research: Space Physics, 2017, 122 (5), pp. 4943-4959

Author affiliation

/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Physics and Astronomy

Version

  • VoR (Version of Record)

Published in

Journal of Geophysical Research: Space Physics

Publisher

American Geophysical Union (AGU)

issn

2169-9380

eissn

2169-9402

Acceptance date

2017-03-05

Copyright date

2017

Available date

2017-09-11

Publisher version

http://onlinelibrary.wiley.com/doi/10.1002/2017JA023904/abstract

Language

en