Fig. 17From: Double-thin-shell approach to deriving total electron content from GNSS signals and implications for ionospheric dynamics near the magnetic equatorTEC maps derived by single-shell model. a–c Vertical TEC for shell heights of 350, 450, and 550 km; and d–f difference between TEC in left panels and two-shell TEC in Fig. 15a with shell height combination of 300 and 600 kmBack to article page