The Bureau Central de Magnétisme Terrestre (BCMT) is a French organization founded in 1921 and attached to the Institut de Physique du Globe de Paris (IPGP). Two French institutions are involved in BCMT operations: IPGP and École et Observatoire des Sciences de la Terre de Strasbourg (EOST). The primary mission of the BCMT is to provide ground geomagnetic observations of the highest quality to the scientific community, in France and abroad. To achieve its mission,...