Fig. 4From: Monitoring the ionospheric total electron content variations over the Korean Peninsula using a GPS network during geomagnetic stormsThe diurnal vertical TEC variation at a specific point (37° N, 127°E) over South Korea on 3–5 November 2003 using KGN data. The blue line represents the vertical TECU obtained by the KASI regional ionosphere model. The red dotted line is the diurnal median TEC variation obtained for 10 quiet days (Kp < 4).Back to article page