Figure 3From: Impacts of solar activity on performance of the IRI-2012 model predictions from low to mid latitudes The diurnal variations of GPS-TEC and different IRI models at NTUS. Comparison of hourly mean IRI 2012 model TEC for three topside Ne, IRI-NeQ, IRI01-corrand IRI-2001 with ground-based GPS-TEC during 2009 to 2013 at Singapore (NTUS) for (a) summer, (b) winter, (c) and equinox.Back to article page