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The conductivity is an important ionospheric parameter since it define the current systems in the high atmosphere and the magnetosphere. As direct estimation of conductivity in real time is not possible, it is estimated using plasma theory and atmospheric ground measurement or modeling instead. One of the most widely used models to estimate the ionospheric parameters is the International Reference Ionosphere (IRI). IRI is constantly improved thanks to the efforts of a great worldwide community, making it a very reliable model of the ionosphere. Any new model included to IRI change the way to calculate some parameters, and consequently modify the output of the code. In this work we analyze how much IRI F-layer model options can affect the estimation of ionospheric Hall and Pedersen conductivity and conductance for the day and at night. The models analyzed are estimators of height and frequency of the F2 peak, hmF2 and foF2, and, the shape and thickness of this layer, called B0 and B1. Models of foF2 slightly affect the conductance calculation, negligible in Hall case and <10% in Pedersen case, reaching 15% in particular zones at noon, but at night can be reached 150% of difference. B0–B1 models modify the conductance calculation mainly over northern region of magnetic equator during the day, but at night, variations of up to 90% are observed in the case of Pedersen. The hmF2 models obtain the maximum rate of change, being up to 60% in some areas at noon, while at night, it can reach 210% difference for Pedersen. • Ionospheric conductance varies according to different IRI setting options. • The choice of hmF2 and foF2 models widely affects ionospheric conductance. • Pedersen conductance is more affected by IRI models. [ABSTRACT FROM AUTHOR]

High frequency (HF) electromagnetic wave propagation is commonly used in long-distance communication and detection. The ionosphere is a highly variable medium affecting this propagation. However, mean climatological conditions are useful in order to determine a "base level" for the design and operation of systems using HF waves that propagate in the ionosphere. Important variables that determine these conditions are the ionosphere peak height, hmF2, and F2 critical frequency, foF2. In the present work the effect of different hmF2 and foF2 model options in IRI-2016 and its spatial variability are analyzed through the analysis of the ground range and reflection height of HF ray paths using a numerical ray tracing method. The model options are M(3000)F2, AMTB and SDMF2 for hmF2, and URSI and CCIR for foF2. We perform this study for a quiet day, April 26 at 12 LT, and solar activity maximum conditions. Ground range and reflection height variation between values obtained with the different model options are on average not greater than ~40%, but can be higher for a Pedersen ray case. These variations are in general much stronger than those obtained when Earth's magnetic field is neglected in ray path assessments. However, while the magnetic field effect is of "physical" origin that has always the same sign, the effect of changing a model used for certain parameter's estimation depends on the model performance which may vary with location and time. • Ray tracing is used to study HF wave propagation for different IRI setting options. • Ground range values vary appreciably with the choice of hmF2 and foF2 models. • The effect of neglecting the Earth's magnetic field is in general smaller. [ABSTRACT FROM AUTHOR]