Day-by-day modelling of the ionospheric F2-layer for year 2002

The thermosphere–ionosphere–mesosphere-electrodynamics general circulation model (TIME-GCM) has been run for the year 2002. Its version 1.2 features include day-by-day input of solar irradiance, geomagnetic energy input parameterized by the 3-h Kp index, and global lower boundary conditions from the National Centres for Environmental Prediction (NCEP) data. In addition, it includes tidal forcing from the global-scale wave model (GSWM) and parameterized gravity waves from below. The computed day-by-day values of noon peak electron density NmF2 agree well with ionosonde data for five northern sites and two southern mid-latitude sites, and closely follow the day-by-day modelled concentration ratio of atomic oxygen to molecular nitrogen. Seasonal and hemispheric patterns appear in the model with some, though not full, success. The model's day-to-day patterns show an impressive degree of variability, with simulations of total variability both above and below those observed.