Figure 4From: Patterns of GPS-TEC variation over low-latitude regions (African sector) during the deep solar minimum (2008 to 2009) and solar maximum (2012 to 2013) phases A graph to depict diurnal hourly VTEC variation during the solar minimum phase (2009). The figure shows the VTEC variation over Nazret (station number 4) in the sampled days with their corresponding Ap index.Back to article page