Sun - Earth interaction
Sun’s activity, dynamics and variability have a great influence on the Earth system and on the circumterrestrial medium in terms of both climatic and geomagnetic variations. Particularly, Sun’s coronal activity, resulting from the solar magnetic field evolution and consisting of impulsive phenomena (e.g. flares, coronal mass ejection, etc.) during which matter (plasma) is ejected into the interplanetary space, has a strong impact on the geomagnetic field conditions and on the magnetosphere-ionosphere system. Phenomena originating from this interaction are mostly impulsive and are the so-called magnetic storms and sub-storms and produce alterations of the geomagnetic field that are visible trough shining phenomena such as auroras. The interest in understanding these phenomena has been more and more increasing for the last 30 years as a consequence of the great impact that the magnetic field alterations have on large scale on both communication systems and electrical networks on the Earth.
