“…They mainly focus on two folds, that is, the ionospheric response and its effects on GNSS positioning service. They characterized the ionospheric irregularities of different regions, such as China (Ning & Tang, 2018; Sun et al, 2017), Norway (Jacobsen & Andalsvik, 2016), India (Yadav et al, 2016), high‐latitude region (Cherniak et al, 2015), low‐latitude region (Maurya et al, 2018), South America (Barbosa et al, 2018), African equatorial/low‐latitude region (Amaechi et al, 2018), European‐African region (Borries et al, 2016), and the global scale. At the same time, they also used different instruments or data, including ground‐based GNSS data, ionosondes data, TSX data, GRACE data, Swarm data, GUVI, Jason‐2, and GPS data on Jason‐2 for understanding the geomagnetic storm (Astafyeva et al, 2015; Chen et al, 2016; Jin et al, 2017; Kuai et al, 2016; Nava et al, 2016; Prikryl et al, 2016).…”