Observations of high-velocity SAPS-like flows with the King Salmon SuperDARN radar
In this study, a focused investigation of the potential for the King Salmon (KS) SuperDARN HF radar to monitor high-velocity flows near the equatorial edge of the auroral oval is undertaken. Events are presented with line-of-sight velocities as high as 2km/s, observed roughly along the L-shell....
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2006-07-01
|
| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/24/1591/2006/angeo-24-1591-2006.pdf |
| Summary: | In this study, a focused investigation of the potential for the King Salmon
(KS) SuperDARN HF radar to monitor high-velocity flows near the equatorial
edge of the auroral oval is undertaken. Events are presented with
line-of-sight velocities as high as 2km/s, observed roughly along the
L-shell. Statistically, the enhanced flows are shown to be typical for the
dusk sector (16:00–23:00 MLT), and the average velocity in this sector is
larger (smaller) for winter (summer) conditions. It is also demonstrated
that the high-velocity flows can be very dynamical with more localized
enhancements existing for just several minutes. These short-lived
enhancements occur when the luminosity at the equatorial edge of the auroral
oval suddenly decreases during the substorm recovery phase. The short-lived velocity enhancements can be
established because of proton and ion injections into the inner
magnetosphere and low conductance of the ionosphere and not because of
enhanced tail reconnection. This implies that some KS velocity enhancements
have the same origin as subauroral polarization streams (SAPS). |
|---|---|
| ISSN: | 0992-7689 1432-0576 |