Olaniyi et al
Greener Journal of Physical Sciences Vol. 3 (2), pp. 058-065, February 2013.
ISSN: 2276-7851 © 2011 Greener Journals
Manuscript Number: 011813394
Variability of hmF2 over San Vito: Comparison with International Reference Ionosphere (IRI) Model Predictions
Olaniyi G.A.*, Adewale A.O. and Oyeyemi E.O.
Physics Department, University of Lagos, Yaba, Nigeria.
*Corresponding Author’s Email: ganeey24 @ yahoo.com.
mid-latitude station was selected for this study to
investigate the variations in the diurnal and seasonal
median values of the height of the peak electron density of
the F2-layer of the ionospheric region. Namely, San Vito
(SAN)(40.60N,17.80E). Data were arranged into seasons as
follow: December Solstices (November, December and January),
March Equinox (February, March and April), June Solstices
(May, June and July) and September Equinox (August,
September and October). The diurnal and seasonal mean values
were calculated, recorded and used in the analysis and
comparison, this is the basis of this study. Two distinct
solar activity periods were considered: 2001-2002 and
2007-2008 which were high solar activity (HSA) and low solar
activity (LSA) periods respectively. Observed values were
analysed and compared with predicted values of the
International Reference Ionosphere (IRI-2007) model, using
the two options of CCIR and URSI. The diurnal and seasonal
patterns of the observed values are predicted fairly well by
the IRI-2007 model, though; there were overestimations and
underestimations at different times of the day for both
solar activity periods in all the seasons considered. The
CCIR option of the IRI-2007 model performed better in the
analysis of the predicted values, though, both the CCIR and
URSI gave hmF2 values closed to the observed ones for the
solar activity periods considered.
Keywords: IRI-2007 model, CCIR, URSI models