International Reference Ionosphere (IRI) is a common permanent scientific project of the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI) started 1968/69. It is the international standard empirical model for the terrestrial ionosphere since 1999. For a specified geographic location, time, and date, IRI provides average monthly values for electron density, electron temperature and ion temperature, and the molecular composition of the ions in the range of altitudes from 50 km to 2000 km.[1] The latest standard is IRI-2012.[1][2] A new version, IRI-2016, has since been released.[3] The IRI has been extended to plasmasphere in the IRI-Plas model.[4]