Geomagnetism is the branch of geophysics that deals with the study of the Earth's magnetic field and its mathematical models. It is known that most of the earth's magnetic field is generated in the Earth's fluid outer core, with a small contribution from the magnetized earth's crust and with an even smaller but not negligible contribution from the electromagnetic phenomena that take place in the circumterrestrial space, in the ionosphere and in the magnetosphere. A consequence of the multiplicity of sources of this field is that its evolution in time and space takes place on scales ranging from a few seconds to tens of millions of years and from a few kilometers to thousands of kilometres.
In addition to moving the magnetic needle of a compass to indicate the direction of north, the magnetic field plays a very important role in shielding the planet from the continuous flow of radiation and charged particles emitted by the Sun, the so-called solar wind, and from its impact negative about the delicate balance of life on Earth.
The group of researchers and technicians related to geomagnetism at INGV deals with the study of variations (in time and space) of the Earth's magnetic field both of internal origin (nuclear and crustal) and external to the Earth (ionospheric and magnetospheric ), contributing to a better knowledge of complex phenomena that have scientific implications and repercussions on technological systems and which present aspects that are still unclear or unexplored.
An essential tool for geomagnetism studies is represented by the data collected at the geomagnetic observatories on the ground, both those managed by INGV in Italy and in Antarctica, and those distributed on a global scale, through world databases and consortia such as Intermagnet, which our country also contributes, and from the analysis of data from satellite missions (for example the European constellation Swarm).
Particular attention is paid to the analysis of magnetic variations of external origin and to the characterization of magnetospheric dynamics in response to solar activity, to the study of ionospheric turbulence through the analysis of satellite measurements of the geomagnetic field and some ionospheric parameters, to improve knowledge of some processes responsible for the disturbing effects on technological systems, on the ground (GIC currents) and in space, during periods of intense magnetic activity (Space Weather). The observations from the measurement stations of geomagnetic and ionospheric parameters are made available inside the monitoring and surveillance rooms in order to guarantee the national service for the Space Weather, oriented towards the prediction of phenomena that take place in the circumterrestrial environment, above all in order to mitigate their effect on technological systems. In fact, INGV is a member of the European consortium PECASUS, selected by ICAO (International Civil Aviation Organization) as one of the three world centers for the supply of a global Space Weather service for civil aviation safety.