Abstract In November 2024, the International Association of Geomagnetism and Aeronomy (IAGA) Division V Working Group (V-MOD) adopted the fourteenth generation of the International Geomagnetic Reference Field (IGRF). This IGRF updates the previous generation with a definitive main field model for epoch 2020.0, a main field model for epoch 2025.0, and a predictive linear secular variation for 2025.0 to 2030.0. We describe the equations defining the IGRF, the spherical harmonic coefficients for this fourteenth generation model, maps of magnetic declination, inclination, and total field intensity for the model at 2025.0 and maps of the predicted rate of change of the field for the 2025.0 to 2030.0 time period.
Beggan et al. (Mon,) studied this question.