A new assimilative model for intermediate scale ionospheric structure

An assimilative model for ionospheric particle density structure must include deterministic and stochastic components: N(r,t) = N̅(r,t) (1+δN(r,t)/N0) The component N̅(r,t) can be generated or assimilated with a physics based model. For radio diagnostics this is the TEC component. The spatial large-scale range is hundreds of kilometers to many kilometers with long lifetimes. The stochastic component δN(r,t)/N0 is a fractional modulation that cannot be predicted in detail. The intermediate scale range from tens of kilometers to hundreds of meters is persistent to the extent that it can be considered frozen over typical measurement intervals. Small-scale structure below a few hundred meters is associated with enhanced plasma-waves that require more detailed characterization. In this paper only intermediate scale structure will be considered.