Modelling the effects of ionospheric disturbances on quasi-vertically incident ionograms using 3D magneto-ionic raytracing

Ionospheric disturbances are manifest over a large range of spatial and temporal scales. Currently DSTO has a good understanding of these disturbances at the largest scales (>; 1000 km and >; 15 min) through its network of vertical incident (VI) sounders. However, we are interested in investigating these disturbances at much smaller scale sizes. To this end DSTO has initiated an experimental programme, SpICE (Spatial Ionospheric Correlation Experiment), utilising state-of-the-art DSTO designed high frequency (HF) digital receivers. This programme seeks to understand ionospheric disturbances at scales <; 150 km and temporal resolutions under 1 minute through the simultaneous observation and recording of quasi-vertical ionograms (QVI) with closely spaced ionospheric control points. The rst experimental campaign was conducted in February 2008. A detailed description of and early results from this campaign were presented by [1] and [2]. Since then there have been a further 2 campaigns which are described by [3]. In this paper we show how 3D magneto-ionic Hamiltonian raytracing techniques can be used to model and understand the various ionospheric disturbances seen in the data.