International Reference Ionosphere Model
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Model Developer(s)
D. Bilitza, NASA/GSFC
URSI/COSPAR Working Group on IRI
Model Description
The International Reference Ionosphere (IRI) is an international project sponsored by the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI). These organizations formed a Working Group in the late sixties to produce an empirical standard model of the ionosphere, based on all available data sources charter. Several steadily improved editions of the model have been released. For given location, time and date, IRI describes the electron density, electron temperature, ion temperature, and ion composition in the altitude range from about 50 km to about 2000 km; and also the electron content. It provides monthly averages in the non-auroral ionosphere for magnetically quiet conditions. The major data sources are the worldwide network of ionosondes, the powerful incoherent scatter radars (Jicamarca, Arecibo, Millstone Hill, Malvern, St. Santin), the ISIS and Alouette topside sounders, and in situ instruments on several satellites and rockets. IRI is updated yearly during special IRI Workshop, e.g., during COSPAR general assembly). More information can be found in the workshop reports. Several extensions are planned, including models for the ion drift, description of the auroral and polar ionosphere, and consideration of magnetic storm effects.
An IRI Newsletter is published quarterly. Please contact the Newsletter editor K. Oyama if you would like to be included on the distribution list. There is also an electronic mailer with uptodate IRI-relevant information.
The IRI master copy is held at the National Space Science Data Center (NSSDC) and updated according to the decisions of the Working Group. The software package distributed by NSSDC includes the FORTRAN subroutines, model coefficients (CCIR and URSI), and documentation files. The IRI build-up and formulas described in detail in a 158-page NSSDC report (Bilitza, 1990).
Model Output
Electron density, electron temperature, ion temperature, ion composition (O+, H+, He+, NO+, O+2), ion drift, TEC
References and relevant publications
K. Rawer, D. Bilitza, and S. Ramakrishnan, Goals and Status of the
International Reference Ionosphere, Rev. Geophys., 16, 177-181, 1978.
K. Rawer, S. Ramakrishnan, and D. Bilitza, International Reference Ionosphere
1978, International Union of Radio Science, URSI Special Report, 75 pp.,
Bruxelles, Belgium, 1978.
K. Rawer, J. V. Lincoln, and R. O. Conkright, International Reference
Ionosphere-IRI 79, World Data Center A for Solar-Terrestrial Physics, Report
UAG-82, 245 pp., Boulder, Colorado, 1981.
K. Rawer and C. M. Minnis, Experience with and Proposed Improvements of the
International Reference Ionosphere (IRI), World Data Center A for
Solar-Terrestrial Physics, Report UAG-90, 235 pp., Boulder, Colorado, 1984.
D. Bilitza (ed.), International Reference Ionosphere 1990, NSSDC 90-22,
Greenbelt, Maryland, 1990.
D. Bilitza, K. Rawer, L. Bossy, and T. Gulyaeva, International
Reference Ionosphere - Past, Present, Future, Adv. Space Res. 13, #3,
3-23, 1993.
D. Bilitza, International Reference Ionosphere - Status 1995/96,
Adv. Space Res. 20, #9, 1751-1754, 1997.
D. Bilitza, International Reference Ionosphere 2000,
Radio Science 36, #2, 261-275, 2001.
D. Bilitza, International Reference Ionosphere 2000: Examples of improvements and new features, Adv. Space Res. 31, #3, 757-767, 2003.
B. Reinisch and D. Bilitza, Karl Rawer's life and the history of IRI, Adv. Space Res. 34, #9, 1845-1950, doi:10.1016/j.asr.204.09.002, 2004.
D. Bilitza and Reinisch, B., International Reference Ionosphere 2007: Improvements and new parameters, J. Adv. Space Res., doi:10.1016/j.asr.2007.07.048, 2008
Relevant links
PC Windows version from University of Mass. Lowell site
Source Code Available on FTP:
ftp://hanna.ccmc.gsfc.nasa.gov/pub/modelweb/ionospheric/iri
CCMC Contact(s)
301-286-9571
Developer Contact(s)
301-286-0190







