Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1777474 | Journal of Atmospheric and Solar-Terrestrial Physics | 2010 | 5 Pages |
Abstract
Auroral arcs can develop small-scale distortions known as vortex streets or curls. Other common and somewhat larger spatially periodic distortions are auroral folds. In this event study we present simultaneous wide and narrow field imager observations of a third kind of structuring, on even smaller spatial scales. Boundary undulations, or “ruffs”, have been observed to form on the edge of an auroral arc and they occur superimposed on curls, folds or at times of auroral shear. The undulations typically have wavelengths of less than 3Â km and amplitudes of less than 800Â m. They are observed to move on the edge of the arc, with velocities of about 11Â km/s. These observations, with multi-scale deformations, reveal a much more intricate structuring of auroral arcs than previously found.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geophysics
Authors
H. Dahlgren, A. Aikio, K. Kaila, N. Ivchenko, B.S. Lanchester, D.K. Whiter, G.T. Marklund,