Geospatial Coordinate Reference System International Geomagnetic Reference Field Alken, P., Thébault, E., Beggan, C.D. et al. International Geomagnetic Reference Field: the thirteenth generation. Earth Planets Space 73, 49 (2021). https://doi.org/10.1186/s40623-020-01288-x , https://www.iaga-aiga.org/ This global main field model provides magnetic field values for any location on Earth, e.g. for navigational purposes (declination) or as a standard for core field subtraction for aeromagnetic surveys. An updated version is adopted by International Association of Geomagnetism and Aeronomy (IAGA) every 5 years).