F2 region maximum electron density height predictions for South American latitudes

Abstract

[1] Values of the F2 region maximum electron density height (hmF2) calculated using ground ionosonde data at South American latitudes are used to check the validity of the International Reference Ionosphere (IRI) to predict this variable. With this in mind we compare hmF2 predictions given by the model when measurements of critical frequency of F2 region and propagation parameter M(3000)F2 were used as input parameter in IRI (hmF2 IRI-Exp ), against those obtained using the standard International Radio Consultative Committee (CCIR) option (hmF2 IRI-CCIR ). In this paper we used hmF2 IRI-Exp values because hmF2 measurements were not available for the considered cases. Moreover, a comparison of the measured M(3000)F2 values with the CCIR predictions have been done. The results show that, in general, the standard predictions follow the diurnal tendency observed in the hmF2 IRI-Exp values. At low latitudes the hmF2 IRI-Exp values show oscillations not reproduced by the standard option. Cases with disagreements for 24 hours have been observed at high latitudes. Other cases with good agreement have been also obtained. The results suggest that, in general, the standard option of the model gives good hmF2 predictions at South American latitudes. Few cases showed deviation between 15 and 25%. As we expected, the obtained results suggest that the deviation between predicted and measured M(3000)F2 values is the main contribution for the deviation between hmF2 IRI-CCIR and hmF2 IRI-Exp . The comparison with the results obtained in previous work shows that the IRI performance in predicting M(3000)F2 and hmF2 is better than in predicting foF2.

Validation of Jason-1 Nadir Ionosphere TEC Using GEONET

“…IRI is a widely used standard for specification of ionospheric parameters, including electron density, TEC, ion densities, electron temperature, ion temperature and ion drift (Bilitza 2001). IRI has been steadily improved and updated by a joint working group of the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI) (e.g., Ezquer et al 2003). This model has been extensively used for ionospheric calibrations and predictions.…”

Peak characteristics of F2 region over Tucumán: Predictions and measurements

“…Values of the F2 region maximum electron density height (hmF2) obtained from ground ionosonde data at South American latitudes were used by Ezquer et al (2003) to check the validity of the IRI model to predict this variable. To this end they compared hmF2 predictions given by the model when ground ionosonde data were used as an input parameter in the model (hmF2 IRIÀExp ), against those obtained using the standard option (hmF2 IRIÀCCIR ).…”

Computer simulation of the sky wave propagation through the disturbed ionosphere

“…The simplest approach to describe the radio wave propagation through the ionosphere is to solve for the index of refraction. Thus, substituting the following equation The homogeneous ionized gas (ionosphere) behaves like an imperfectly conducting medium with conductivity i and dielectric constant i ' which are given by [10] as…”

“…Several physical, empirical, and semiempirical models [4][5][6][7][8] have been developed to predict ionospheric variables. Measurements of the critical frequencies of the ionospheric regions (f o E, f o F1, and f o F2) obtained at South America stations for different solar conditions and seasons were used in [9][10] to check the validity of the international reference ionosphere (IRI) model. Several computer programs have been developed for the analysis of ionospheric communication links such as ICEPAC [11], IONCAP [12], VOACAP [13], and their parent model, ITSA [14].…”