C4.1 Improved Representation of the Ionosphere in Real-Time and Retrospective Mode

COSPAR General Assembly, Moscow, Russia, August 5-6

Report, D. Bilitza

Session C4.1 was organized by the COSPAR/URSI Working Group on the International Reference Ionosphere (IRI) and was convened by D. Bilitza and T. Gulyaeva. The main focus was on the development of the Real-Time IRI , however, other IRI-related topics were discussed as well. The session was well attended with about 45 particpants and with at times standing room only. 37 oral and 17 poster presentation were scheduled over a 2-day period.  9 oral papers and 7 posters were withdrawn and two additional oral presentation were included in the program. The session was divided into 6 sections: (1) Real-time IRI, (2) Topside and TEC , (3) F-region mapping, (4) Comparisons with IRI, (5) New inputs for IRI, (6) Posters.


A number of groups are engaged in activities towards the development of a Real-Time IRI using different techniques and data sources towards this goal. The University of Massachusetts Lowell (UML) team has presented one of the most advanced and mature system with their IRI Real Time Assimilative Mapping (IRTAM) technique that updates the CCIR coefficients for the F-peak density and height with the help of digisonde data from the Global Ionosphere Radio Observatory (GIRO) network. Latest results and validation efforts were reported by I. Galkin and A. Vesnin. At auroral latiudes Y. Zhang (APL, USA) has succeeded in using TIMED/GUVI and DMSP/SSUSI data to bring auroral boundary and E-region densities in IRI to real-time conditions. In the European sector local and regional assimilative methods are being succesfully applied to IRI using single or regional ionosonde inputs (M. Pezzopane, Italy; H. Haralambous, Cyprus). S. Jun Oh (Korea) reported on a regional HF frequency prediction service based on assimilating data from a local ionosonde into IRI. GPS data are an important data source for real-time monitoring and modeling of the ionosphere (M. Hernandez, Spain; M. Alizadeh, Germany), however they require tomographic or radio occultation techniques if information about the altitudinal structure of the ionosphere is required.


Presentations during the IRI session utilized numerous data sources including measurements by ionosondes/digisondes, incoherent scatter radars, SuperDARN HF radars (Oinats, Russia), SAURA Doppler radar (Singer & Strelnikova, Germany), TIMED, DMSP, COSMIC, GPS, ISIS, Alouette, ROCSAT-1, Hinotori, Topex, and Jason satellites, and Rockets (J. Shi, China).  A comprehensive study of EISCAT incoherent scatter data with IRI by L Bjoland (Norway) covering more than two solar cycles will be an important starting point for improvements of IRI parameters at high latitudes. Comparisons of digisonde data from Multan, Pakistan again showed the need for improvements of IRI during the extremly low  solar cycle minimum in 2008/2009 (M. Ameen, Pakistan). New models were presented for the upper ion transition height based on Alouette and ISIS topside sounder data and COSMIC radio occultation data (V. Truhlik, Czech Republic) and for the ion density around 600 km based on ROCSAT-1 data (L. Liu, China).


During the IRI business meeting the working group decided on two important  improvements for the next version of the IRI model: (1) as separate options for hmF2 the model by Altadill et al. (Spain) based on digisonde data and the model by Karpachev et al. (Russia) based on COSMIC radio occultation data; (2) Auroral NmE and hmE based on Zhang’s (APL, USA) work with TIMED/GUVI and DMSP/SSUSI data. High priority was given to the inclusion of a plasmaspheric extension into IRI starting possibly with the IRI-Plas option developed by Gulyaeva (Russia). One problem, however, are the still existing uncertainties of the topside profile shape especially during very low solar activity (Bilitza, USA).  The IRI Real-Time effort will continue with developing a scheme for assimilating GIRO digisonde data for the bottomside parameters B0, B1, and D1 into IRI (Galkin, USA),


Advances in Space Research has agreed to the publication of a special issue on the IRI in Real-Time and Retrospective Mode. Oral and poster presenters from session C4.1 are invited to submit their contributions to the special issue. The issue will be open to other IRI-related contributions as well; presentation at the meeting is not a prerequiste for publication in the special issue.


The 2015 IRI Workshop will be held in Bangkok, Thailand as a COSPAR Capacity Building Workshop. Prasert Kenpankho from the King Mongkut's Institue of Technology Ladkrabang (KMITL) in Bangkok gave a presentation describing the workshop plans and location. The first week will be lectures and seminars for students, and the second week will have the usual IRI Workshop format with science talks including also presentations by the students about their respective project results from the first week. More information will be soon available on the IRI homepage at http://irimodel.org .


During its business meeting the IRI Working Group elected its new leadership team for the next four years. David Altadill (Ebro Observatory, Spain) was elected as new IRI Chair and Shigeto Watanabe (Hokkaido University, Japan) and Vladimir Truhik (IAP, Czech Republic) were re-elected as Vice-Chairs for COSPAR and URSI, respectively. Feza Arikan (Hacettepe University, Turkey) was elected as a new member to the IRI Working Group. The IRI steering committee also includes the former Chairs L.-A. McKinnell (SANSA, South Africa), B. Reinisch (LDI, USA) and D. Bilitza (GMU, USA).