Equatorial spread F (ESF) is a low-latitude ionospheric phenomenon that leads to the development of large scale electron density depletions that adversely affect communications and navigation systems. The development of models to understand and predict the onset and evolution of ESF is therefore critically important to a number of space-based systems. To this end, a new two-dimensional simulation code NRLESF2 to model equatorial spread F has been developed at the Naval Research Laboratory. The code uses an 8th order spatial interpolation scheme and the partial donor cell method as a flux limiter which allow simulation studies with very low numerical diffusion. We present new results of the dynamics of equatorial spread F that exhibit multiple bifurcations, secondary structure development, and high speed flows within low density channels. We compare these results to all-sky images and radar data.

Research supported by the Office of Naval Research.