Modeling the Ionosphere with SAMI3 (Invited Tutorial)

SAMI3 (Sami3 is Also a Model of the Ionosphere) is a global, comprehensive model of the ionosphere/plasmasphere system. It is based on the SAMI2 model developed at the Naval Research Laboratory (Huba et al., 2000). SAMI3 models the plasma and chemical evolution of seven ion species (H, He, N, O, N, NO and O). The ion temperature equation is solved for three ion species (H, He and O) as well as the electron temperature equation. Ion inertia is included in the ion momentum equation for motion along the geomagnetic field. The neutral composition and temperature can be specified by empirical models (e.g, NRLMSISE00, HWM14) or by first-principle atmosphere models (e.g., TIEGCM, WACCM-X, HIAMCM). SAMI3 uses a nonorthogonal, nonuniform, fixed grid. The grid is designed to optimize the numerical mesh so that the spatial resolution decreases with increasing altitude. SAMI3 can use an untilted or tilted dipole model of earth’s magnetic field, or an IGRF field model based on the Richmond apex model. A general overview of ionospheric physics and the SAMI3 model will be presented, as well as several applications of the code.