ISSN 2070-7401 (Print), ISSN 2411-0280 (Online)
Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa


Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2014, Vol. 11, No. 1, pp. 75-84

Ionospheric parameters: FormoSat-3/COSMIC radio occultation data, ionosonde measurements, IRI and NeQuick model data

E.S. Andreeva1 , M.V. Lokotа1 
1 M.V. Lomonosov Moscow State University, Moscow, Russia
The results of comparisons of the IRI-2001, IRI-2007, NeQuick models with the radio occultation profiles for different geomagnetic conditions are reported. Our analysis showed that models NeQuick, IRI-2001, IRI-2007 rather well reproduce the maximum values of electron density and much worse electron density profiles. Values of VTEC, simulated by IRI and NeQuick models, in comparison with values calculated from radio occultation profiles are overestimated. The largest differences were detected in the region of the Equatorial anomaly. The best results were achieved in comparison with IRI-2007 model data.Verification results of FormoSat-3/COSMIC radio occultation data based on ionosonde measurements in different regions of the world during the period of 2006-2008 are presented. The discrepancy in the F2-layer critical frequencies from radio occultation profiles and ionosonde data increases with ionospheric storminess enhancement. Generally in comparison with radio occultation profiles ionosonds showed overestimated values. Large differences between the values of critical frequencies in Taiwan area both during disturbed and quiet geomagnetic conditions were observed.
Keywords: ionosphere, ionospheric models, radio occultation method, critical frequencies, electron density, totalelectron content
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