High-latitude ionospheric irregularities during the 25–26 August 2018 geomagnetic storm as seen by ground-based and space-borne instruments

In this work, we analyze the occurrence of ionospheric irregularities during the 25–26 August 2018 geomagnetic storm. With the minimum SYM-H excursion of −206 nT, this storm is the third largest in the solar cycle 24. It produced strong effects in the ionosphere, especially in the American and Pacific longitudinal sectors. Here we use a combination of ground-based (GNSS) and spaceborne (Swarm and CSES) instruments in order to detect the occurrence of intensive ionospheric irregularities. We show that the most significant impact was done at high-latitudes. In the North American region, the area with irregularities descended to 42-45N. The location of the observed irregularities corresponded, most likely, to the auroral oval region. The use of satellite measurements added more information on the spatial distribution of the irregularities, which is especially important in areas with limited coverage by ground-based GNSS stations.