Fig. 8From: Analysis of temporal–longitudinal–latitudinal characteristics in the global ionosphere based on tensor rank-1 decompositionLarge-scale longitudinal variations in the ionosphere for the 12 UTs during the geomagnetic quiet time. The red dotted line indicates the longitude position of the maximum \(U^{(2)}\). The black dotted line indicates the longitude position of the maximum solar irradiation. The x-axis is the geographic longitude ranging from \(-\,180^{\circ }\) to \(180^{\circ }\)Back to article page