TIME3D-IGGCAS: A new three-dimension mid- and low-latitude theoretical ionospheric model in realistic geomagnetic fields

► TIME3D-IGGCAS is a three‐dimension mid‐ and low‐latitude theoretical ionospheric model. ► It bases on magnetic APEX coordinates, and achieves the ionospheric simulation in realistic geomagnetic fields. ► TIME3D-IGGCAS can well reproduce the main ionospheric features. ► The differences between simulated NmF2 in realistic geomagnetic fields and that in tilted dipole fields can be larger than 40%.