Journal of Geodesy

, Volume 85, Issue 12, pp 909–920 | Cite as

The international reference ionosphere today and in the future

  • Dieter BilitzaEmail author
  • Lee-Anne McKinnell
  • Bodo Reinisch
  • Tim Fuller-Rowell


The international reference ionosphere (IRI) is the internationally recognized and recommended standard for the specification of plasma parameters in Earth’s ionosphere. It describes monthly averages of electron density, electron temperature, ion temperature, ion composition, and several additional parameters in the altitude range from 60 to 1,500 km. A joint working group of the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI) is in charge of developing and improving the IRI model. As requested by COSPAR and URSI, IRI is an empirical model being based on most of the available and reliable data sources for the ionospheric plasma. The paper describes the latest version of the model and reviews efforts towards future improvements, including the development of new global models for the F2 peak density and height, and a new approach to describe the electron density in the topside and plasmasphere. Our emphasis will be on the electron density because it is the IRI parameter most relevant to geodetic techniques and studies. Annual IRI meetings are the main venue for the discussion of IRI activities, future improvements, and additions to the model. A new special IRI task force activity is focusing on the development of a real-time IRI (RT-IRI) by combining data assimilation techniques with the IRI model. A first RT-IRI task force meeting was held in 2009 in Colorado Springs. We will review the outcome of this meeting and the plans for the future. The IRI homepage is at


Ionosphere IRI Empirical model F2 peak models Topside 


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Dieter Bilitza
    • 1
    • 2
    Email author
  • Lee-Anne McKinnell
    • 3
  • Bodo Reinisch
    • 4
  • Tim Fuller-Rowell
    • 5
  1. 1.Space Weather LaboratoryGeorge Mason UniversityFairfaxUSA
  2. 2.Heliospheric LaboratoryNASA Goddard Space Flight CenterGreenbeltUSA
  3. 3.Hermanus Magnetic ObservatoryHermanusSouth Africa
  4. 4.Center for Atmospheric ResearchUniversity of Massachusetts LowellLowellUSA
  5. 5.CIRES University of Colorado and NOAA Space Weather Prediction CenterBoulderUSA

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