International reference ionosphere 2000: Examples of improvements and new features Original Research Article

This paper describes the changes that were implemented in the new version of the COSPAR/URSI International Reference Ionosphere (IRI-2000). These changes are: (1) two new options for the electron density in the D-region, (2) a better functional description of the electron density in the E-F merging region, (3) inclusion of the F1 layer occurrence probability as a new parameter, (4) a new model for the bottomside parameters B0 and B1 that greatly improves the representation at low and equatorial latitudes during high solar activities, (5) inclusion of a model for foF2 storm-time updating, (6) a new option for the electron temperature in the topside ionosphere, and (7) inclusion of a model for the equatorial F region ion drift. The main purpose of this paper is to provide the IRI users with examples of the effects of these changes.