“…Furthermore, many authors (Kavanagh et al, 2004;Ondraskova, 2005;Ohya et al, 2006;Pirog et al, 2006;Tsurutani et al, 2006, for instance) agree that extreme solar flares can lead to extreme ionospheric effects. Enhancements in ionospheric total electron content of $ 30% nominal values were observed in association to the Bastille Day, 2000 flare.…”