New B0 and B1 models for IRI Original Research Article

The electron density profile in the F region bottomside is described in the International Reference Ionosphere (IRI) by two parameters: a thickness parameter B0 and a shape parameter B1. The models used for B0 and B1 in IRI are based on ionosonde data from magnetic mid-latitude stations. Comparisons with ionosonde data from several stations close to the magnetic equator show large discrepancies between the model and the data. We propose new models for B0 and B1 based on data from several ionosondes including low and mid latitude stations. Close to the magnetic dip equator the new B0 model provides an improvement over the current IRI model by a factor of up to 1.5.