• The Task Group was established to develop and improve a standard model of the ionospheric plasma parameters. The model should be primarily based on experimental evidence using all available ground and space data sources; theoretical considerations can be helpful in bridging data gaps and for internal consistency checks.

• Where discrepancies exist between different data sources the IRI team should promote critical discussion to establish the reliability of the different data bases.

• IRI should be updated as new data become available and as old data bases are fully evaluated and exploited.

• IRI is a joint working group of COSPAR and URSI . COSPAR’s prime interest is in a general description of the ionosphere as part of the terrestrial environment for the evaluation of environmental effects on spacecraft and experiments in space. URSI’s prime interest is in the electron density part of IRI for defining the background ionosphere for radiowave propagation studies and applications.