Fig. 11
From: PCA and vTEC climatology at midnight over mid-latitude regions
vTECIRI over the North American region: a amplitude of the temporal variation, a 1 (the y-axis has to be multiplied by a factor of 10−2), b eigenvector or spatial variation, e 1, c synthesized data for mode 1 (a 1·e T1 ) for red (east) and blue (west) rectangles, d difference between red and blue curves of Fig. 11c; e the amplitude of the temporal variation, a 2 (the y-axis has to be multiplied by a factor of 10−2), f eigenvector or spatial variation, e 2, g synthesized data for mode 2 (a 2·e T2 ) for red (east) and blue (west) rectangles, h difference between red and blue curves of Fig. 11g. Finally, the time-averaged \(\overline{\text{vTEC}}_{\text{IRI}} \left( x \right)\) (i), the synthesized data, j \(\overline{\text{vTEC}}^{*}_{\text{IRI}} \left( t \right)\), for red (east) and blue (west) rectangles, and the difference (\(\overline{\text{dvTEC}}_{{{\text{IRI}} }}^{*} \left( t \right)\)) between red and blue curves of Fig. 11j (k)