Evaluation of candidate models for the 14th generation International Geomagnetic Reference Field
Year: 2026
Type: article
Abstract: In November 2024, the 14th revision of the International Geomagnetic Reference Field (IGRF) was issued by the International Association of Geomagnetism and Aeronomy (IAGA) Division V Working Group (V-MOD). This revision comprises two new spherical harmonic main field models for epochs 2020.0 (DGRF-2020) and 2025.0 (IGRF-2025) and a model of the predicted secular variation for the interval 2025.0 $$-$$ 2030.0 (SV-2025–2030), all provided as internal Gauss coefficients to degree and order 13 for DGRF-2020 and IGRF-2025, and degree and order 8 for SV-2025–2030. The models were produced from candidates submitted by nineteen international teams. The candidate models were evaluated by an expert international volunteer Taskforce. Comparisons between all candidates as well as to mean, median and Huber-weighted averages of all candidates were made using well-established statistical criteria. These analyses were used to identify, for example, the variation between Gauss coefficients or geographical regions, where the candidate models strongly differed. The majority of candidates were sufficiently close that the differences can be explained primarily by individual modelling methodologies and data selection strategies. None of the candidates were sufficiently different to warrant their exclusion. The IAGA V-MOD Taskforce thus voted for two approaches: the median of the Gauss coefficients of the candidates for the DGRF-2020 and the computed Huber mean in space for the IGRF-2025 and SV-2025–2030 models. In this paper, we document the evaluation of the candidate models and provide details of the approach used to derive the final IGRF-14 products.
Source: Earth Planets and Space
Authors: C. D. Beggan, C. Kloss, A. Grayver, P. Alken, G. Balasis, W. Brown, S. Califf, L. Chauvet, A. Chulliat, M. Fillion, L. Gailler, G. Hulot, M. Korte, V. Lesur, Y. Lin, M. Matsushima, H. McCreadie, T. Minami, M. Nair, S. Nakano, F. J. Pavón-Carrasco, M. Rother, S. Sato, M. Serrano, M. V. da Silva, A. Smith, F. Terra-Nova, E. Thebault, H. Toh, I. Wardinski, C. Xiong
Institutions: British Geological Survey, DTU Space, Technical University of Denmark, University of Cologne, Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, NOAA National Centers for Environmental Information, National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, Centre National de la Recherche Scientifique, Institut de physique du globe de Paris, Université Paris Cité, Université Clermont Auvergne, Observatoire de Physique du Globe de Clermont-Ferrand, Laboratoire Magmas et Volcans, Institut de Recherche pour le Développement, GFZ Helmholtz Centre for Geosciences, Southern University of Science and Technology, Institute of Science Tokyo, Kobe University, The Institute of Statistical Mathematics, Instituto de Geociencias, Kyoto University, University of Edinburgh, Université Nantes Angers Le Mans, Le Mans Université, Laboratoire de Planétologie et Géosciences, Nantes Université, Institut Terre & Environnement de Strasbourg, École & Observatoire des Sciences de la Terre, Université de Strasbourg, Wuhan University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $1,640
OpenAlex ID: W7166592970