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. 2, pp. 255-263

Comparison of critical frequency f0F2 obtained from ionosonde and CAO and IRI models over the Russian Federation

A.A. Titov1 , D.V. Solomentsev1 , V.U. Khattatov1 , B.V. Khattatov2 , V.I. Denysova3 
1 Central Aerological Observatory, Dolgoprudny, Russia
2 Fusion Numerics LLC, Boulder, CO, USA
3 E. K. Fedorov Institute of Applied Geophysics, Moscow, Russia
Accuracy of the assimilative model developed by Central Aerological Observatory (CAO) was estimated by comparisons with ionosonde measurements of the F2 layer critical frequency. The results demonstrate great coherence in the f0F2 diurnal variation. It is shown how often the comparison methods can be applied. The main obstacles are noticed. It is shown, that ionosonde measurements and assimilation modeling results coherence is higher for sounding stations located near regions with high level of GNSS ground stations coverage (the European part of Russia). A comparison of the critical frequency f0F2 data series of international reference ionosphere model IRI and the CAO three-dimensional assimilative ionosphere model is made. These series were collected over a two year and a half period from 1 May 2011 to 1 November 2013. Data regression analysis was made. That allows considering the modeling results dependence on the predictor (ionosonde measurements). IRI critical frequencies overestimation was confirmed by the regression analysis.
Keywords: critical frequency, f0F2 comparison, assimilative model, ionosonde, ionosphere
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