Three-dimensional nonlinear evolution of equatorial ionospheric bubbles with gravity wave seeding and tidal wind effects

Abstract

The three-dimensional nonlinear evolution of equatorial ionospheric bubbles, using a realistic lower atmospheric gravity wave source, has been computed. It is found that three-dimensional finite parallel conductivity effects are important and lead to reduced gravity waveinduced electric fields, less depleted bubbles, and longer time scale bubble evolution compared to the two-dimensional case. It is concluded that nearly zonal propagating gravity waves are needed to excite equatorial ionospheric bubbles in the presence of zonal tidal winds. The simulated ionospheric bubble structures are consistent with recent observations in the SpreadFEx campaign. Citation: Keskinen, M. J., and S. L. Vadas (2009), Three-dimensional nonlinear evolution of equatorial ionospheric bubbles with gravity wave seeding and tidal wind effects, Geophys. Copyright 2009 by the American Geophysical Union.