Multi-scale Modeling and Nested Simulations of Three-dimensional Ionospheric Dynamics: Predicting Ionospheric Variability at Fine Scales

Multi-scale modeling and high resolution three-dimensional simulations of non-equilibrium ionospheric dynamics are major frontiers in the field of space sciences. The latest developments in fast computational algorithms and novel numerical methods have advanced reliable forecasting of ionospheric environments at fine scales. These new capabilities include improved physics-based predictive modeling, nesting and implicit relaxation techniques that are designed to integrate models of disparate scales. A range of scales, from mesoscale to ionospheric micro-scale, are included in a 3D modeling framework. Analyses and simulations of primary and secondary Rayleigh–Taylor instabilities in the equatorial spread F (ESF), the response of the plasma density to the neutral turbulent dynamics, and wave breaking in the lower region of the ionosphere and non-equilibrium layer dynamics at fine scales are presented for coupled systems (ions, electrons and neutral winds), thus enabling studies of mesoscale/micro-scale dynamics for a range of altitudes that encompass the ionospheric E and F layers. We examine the organizing mixing patterns for plasma flows, which occur due to polarized gravity wave excitations in the neutral field, using Lagrangian coherent structures (LCS). LCS objectively depict the flow topology and the extracted scintillation-producing irregularities that indicate a generation of ionospheric density gradients, due to the accumulation of plasma.

A. Mahalov, Multi-Scale Modeling and Nested Simulations of Three-Dimensional Ionospheric Plasmas: Rayleigh-Taylor Turbulence and Non-Equilibrium Layer Dynamics at Fine Scales, Phys. Scr. 89 (2014) 098001 (22pp).