Modeling ionospheric disturbance features in quasi‐vertically incident ionograms using 3‐D magnetoionic ray tracing and atmospheric gravity waves

Abstract

[1] The Defence Science and Technology Organisation (DSTO) has initiated an experimental program, Spatial Ionospheric Correlation Experiment, utilizing state-of-the-art DSTO-designed high frequency digital receivers. This program seeks to understand ionospheric disturbances at scales < 150 km and temporal resolutions under 1 min through the simultaneous observation and recording of multiple quasi-vertical ionograms (QVI) with closely spaced ionospheric control points. A detailed description of and results from the first campaign conducted in February 2008 were presented by Harris et al. (2012). In this paper we employ a 3-D magnetoionic Hamiltonian ray tracing engine, developed by DSTO, to (1) model the various disturbance features observed on both the O and X polarization modes in our QVI data and (2) understand how they are produced. The ionospheric disturbances which produce the observed features were modeled by perturbing the ionosphere with atmospheric gravity waves.Citation: Cervera, M. A., and T. J. Harris (2014), Modeling ionospheric disturbance features in quasi-vertically incident ionograms using 3-D magnetoionic ray tracing and atmospheric gravity waves,

Semiempirical Model for Ionospheric Absorption based on the NRLMSISE‐00 atmospheric model

“…The small difference is due to the downrange variation of the ionosphere. Figure 7 shows a fan of rays with a frequency 15 MHz, at a range of elevation angles, as calculated using the PHaRLAP raytracing software [Cervera and Harris, 2014]. Figure 8 shows the absorption calculated for these rays, as well as similar calculations for other frequencies from 5 to 30 MHz, with SiMIAN results compared with absorption calculated using the Bradley/George model.…”

“…Note that here, the symbol refers to the imaginary component of the refractive index (as used by Davies [1990]) and not the solar zenith angle which it commonly represents. The raypath must first be calculated via raytracing; SiMIAN has been designed to work with the PHaRLAP [Cervera and Harris, 2014] raytracing toolbox. Provision of High-frequency Raytracing LAboratory for Propagation studies includes 2-D and 3-D numerical raytracing engines.…”

“…Figure 13 shows the virtual height data from one ionogram, along with the ionospheric profile calculated by POLAN for this ionogram and virtual height data obtained by simulating an ionogram through this ionospheric profile. The process we used to simulate the ionogram involves raytracing with PHaRLAP's 3-D numerical raytracing engine and is described in detail by Cervera and Harris [2014].…”

Modeling of high frequency radio wave absorption on oblique soundings during a solar X-ray flare

“…Generally, the simulation is focused only on these parameters of the ionogram, which does not require calculation of the signal intensity (Andreev et al, 2003;Tsai et al, 2010;Cervera and Harris, 2014;Krasheninnikov et al, 1996). In order to assess the absorption effects in the ionogram structure, it is necessary to take into account the energy characteristics of the propagation modes.…”

Using IRI and GSM TIP model results as environment for HF radio wave propagation model during the geomagnetic storm occurred on September 26–29, 2011

“…Different methods are widely used to determine ionospheric parameters: simplified analytical representation, observational data, tomography, models, etc. (Huang and Reinisch, 2006;Tsai et al, 2010;Zhbankov et al, 2010;Coleman, 2011;Kryukovsky and Kiryanova, 2011;Pezzopane et al, 2011;Azzarone et al, 2012;Karpachev et al, 2012;Warrington et al, 2012;Settimi et al, 2013;Cervera and Harris, 2014). Many published articles analyze RWP modeling in the middle (Borisova et al, 2009;Lockwood, 1981;Houpis and Nickisch, 1991;Settimi et al, 2013), high (Mingalev et al, 1988;Hunsucker and Hargreaves, 2003;Zaalov et al, 2003;Blagoveshchensky et al, 2010;Warrington et al, 2012;de Larquier et al, 2013) and low latitude ionosphere (Tsai et al, 2010;Zhbankov et al, 2010;Karpachev et al, 2012).…”