On the origin of mesoscale TIDs at midlatitudes

摘要: Abstract. A recent breakthrough experiment by Ogawa et al. (2009) showed that Mesoscale Traveling Ionospheric Disturbances (MSTIDs), a common phenomenon at midlatitudes, originate in the auroral zone as gravity waves. Curiously, however, latter do not seem to be related magnetic activity. These atmospheric waves are high latitudes (Bristow and Greenwald, 1996; Bristow al., 1996), we argue here that, they propagate lower latitudes, Joule damping reduces wave spectrum suffering weakest damping. The direction of corresponds predicted Perkins instability (Perkins, 1973) for nighttime MSTIDs. daytime features reported very likely due classical interaction with F-region ionosphere.