Fig. 2

Time variation of a the F10.7 index used as the simulation input and b obtained TEC variation averaged over 35–39° latitude and 125–147° longitude (red line: under the WJRA setting and orange line: under the WOJRA setting) as functions of UT. c TEC map at UT 0:00 on January 8, 2020, d reference TEC map, i.e., median of TEC at the same UT over the previous 27 days, and e their difference. All from the GAIA simulation carried out on January 6, 2020. The dashed line in a with F10.7 values within brackets indicates the unknown information at the simulation time. Grey hatches in b indicate the significance level of the TEC deviation from the 27-day median values (black line) measured on the I-scale (see details in the text and Appendix), as shown in the color bar on the right-hand side, and pink vertical bands show the start and end times of significant TEC variations. The white boxes in c–e show the region of our interest for ionospheric storm forecasting. The colors of the contour maps for c, d are common