Fig. 9From: Ionospheric irregularity behavior during the September 6–10, 2017 magnetic storm over Brazilian equatorial–low latitudesS4 parameters from LISN GPS receivers from day 07 (12 UT) up to day 09 (12:00 UT). The green line is the noise threshold, i.e., we consider ionospheric scintillation when S4 > 0.15. The vertical dashed red line represents the SSC at 23:00 UT on day 07Back to article page