Service International des Indices Géomagnétiques
International Service of Geomagnetic Indices

Reference service

ISGI is a service of the International Association of Geomagnetism and Aeronomy (IAGA) which recognised "the unique role of the International Service of Geomagnetic Indices (ISGI) in the derivation, publication, and dissemination of these indices" (IAGA, Resolution No. 9 (1989): Appreciation of ISGI activities).

ISGI is in charge of the diffusion of all the IAGA Bulletins relating to geomagnetic indices.

ISGI, through the ISGI Collaborating Institutes, has the responsibility of IAGA geomagnetic indices derivation and dissemination, and to ensure the homogeneity of the data series.

ISGI is the Reference Service for validation, dissemination and stewardship of geomagnetic indices through its official Web portal.


ISGI is an official French National Service of CNRS-INSU which is getting a double label, both in "Solid Earth" TS‑ANO4 (National Observation in Magnetism) and in "Astronomy-Astrophysics" AA‑ANO6 (Surveillance of the Sun and the Earth's Space Environment).