Fig. 4
From: Near-surface atmospheric electric field changes through magnetic clouds via coronal mass ejections
Changes in Ez measured at AZO and STU stations from September 8th–9th, 2017 (panels a and b show the measurement results for the AZO and STU stations, respectively, with a time resolution of 1 min, the vertical axis represents the atmospheric electric field divided by the mean atmospheric electric field, and the pink background lines represent the upper and lower quartiles (25%, 75%) of the atmospheric electric field during other clear sky periods in September. Then, values in the box at bottom right are variations of meteorological parameters, and the numbers in parentheses indicate average values)