Earth’s Lower Ionosphere impacted by High Class X-Ray Solar Flare Events

AbstractSolar activity, especially with its energetic events like solar flares and coronal mass ejections of high intensity, triggers abrupt and strong disturbances within near Earth surroundings, posing the potential hazard to numerous sophisticated technological systems both space-borne and ground-based on one hand, and putting at risk all living life on our planet on the other. Direct influences of events like geomagnetic storms and solar flares on human health were reported in literature. In this paper effects of high class X-ray solar flares form descending branch of 24th solar cycle were analyzed in terms of associated mid-latitudinal lower ionospheric disturbances over European sector, based on simultaneously monitored Very Low Frequency signals’ perturbations as recorded by ground-based receiving system located in Belgrade, Serbia. Conducted numerical simulations revealed electron density increases of several orders of magnitude during maximal impact of analyzed solar flare events. - FULL TEXT available in PDF.