Mesoscale F region neutral winds associated with quasi-steady and transient nightside auroral forms

However, auroral forcing also occurs in various types of mesoscale forms (i.e., tens to hundreds of kilometers in space and a few to tens of minutes in time) and contains more energy input over mesoscale than large scale. A question arises as to whether and how winds respond to the mesoscale forcing.

We characterize F region winds associated with various types of auroral forms using scanning Doppler imagers, auroral imagers, and radars. The auroras examined include a quasi-steady east-west elongated arc, a quasi-steady Harang aurora, transient streamers, and a transient substorm westward traveling surge. We find that winds exhibit distinct spatial structures, appearing as channels, vortices, and reversals.