Fig. 6From: Double-thin-shell approach to deriving total electron content from GNSS signals and implications for ionospheric dynamics near the magnetic equatorEstimation errors of arc biases. a–c Single-shell model with shell heights of 350, 450, and 550 km. d–f Double-shell model with combinations of shell heights of 250/600, 300/600, and 300/700 km for lower/higher shellsBack to article page