EISCAT Svalbard Radar studies of meso-scale plasma flow channels in the polar cusp ionosphere

• Published in: Journal of Geophysical Research: Space Physics
• Main Author: Rinne, Yvonne
• Other Authors: Jøran Moen and Per Even Sandholt
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2010
• Subjects: VDP::430; Longyearbyen; Svalbard; EISCAT
• Online Access: http://hdl.handle.net/10852/10994; http://urn.nb.no/URN:NBN:no-26916

The archipelago of Svalbard is at daytime located underneath the polar cusp, the window towards the interplanetary space. The polar cusp region is where the solar-terrestrial coupling by a process referred to as magnetic reconnection is most direct and strongest. Magnetic reconnetion gives rise to a variety of disturbances like ionospheric flow channels, plasma instabilities or turbulence. The EISCAT Svalbard Radar (ESR) located in Longyearbyen, Svalbard provides, combined with optical observations of daytime auroras, a unique opportunity for detailed studies of plasma processes in the polar cap and the active cusp region. A new azimuth scan mode at the EISCAT Svalbard Radar resulted in high resolution data with good spatial and temporal resolution which proved to be ideal for the study of mesoscale flow channels in the polar cusp ionosphere. The motivation of this thesis was to gain a more thorough understanding of such channels. The emphasis is on two categories of flow channels: Direct reconnection flow channels and the so-called Reversed flow events, opposing the IMF BY associated magnetic tension force. Common for both classes of flow channels is their linkage to magnetic reconnection at the dayside magnetopause. The thesis is organized as follows: First a brief background on magnetic reconnection and ionospheric flow signatures in the ionosphere is given. Then a summary of the four papers in this thesis is presented, followed by a few words about future prospects for this research activity and a list of references.