The GFZ IGRF candidate models and an assessment of secular variation predictions

The GFZ IGRF candidate models and an assessment of secular variation predictions | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The GFZ IGRF candidate models and an assessment of secular variation predictions Martin Rother, Maximilian Schanner, Monika Korte, Ingo Michaelis, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7299497/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 22 Apr, 2026 Read the published version in Earth, Planets and Space → Version 1 posted 5 You are reading this latest preprint version Abstract We outline the creation of the GFZ candidate models for the most recent International Geomagnetic Reference Field (IGRF-14), which is the result of an initiative by a working group of the International Association of Geomagnetism and Aeronomy (IAGA) and is based on candidate models from multiple groups worldwide. For IGRF-14, we largely maintained our Mag.num modelling procedure from the previous IGRF-13, but used a selection of models from an ensemble comprised of three variants: a first model covering a longer period (2000-2024) with data from the CHAMP and Swarm satellites and other sources, a second model variant covering only the Swarm era (2014-2024) using Swarm and observatory data, and a third variant using only in-line and cross-track differences from Swarm data. While changes to data selection and the modelling algorithm are minor compared to our previous IGRF generation candidates, we focus here on describing how our final candidates were derived from this set of parent models. In the second part of this article we look back onto candidates for the last IGRF-13 and their secular variation predictions. In light of the data that has become available over time we use current continuous models and the recent, official IGRF-14 as the ground truth to assess the performance of the different secular variation prediction methods. IGRF magnetic field modelling geomagnetism Full Text Cite Share Download PDF Status: Published Journal Publication published 22 Apr, 2026 Read the published version in Earth, Planets and Space → Version 1 posted Reviewers agreed at journal 08 Dec, 2025 Reviewers invited by journal 03 Dec, 2025 Editor assigned by journal 25 Nov, 2025 First submitted to journal 24 Nov, 2025 Editorial decision: Minor Revision 25 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7299497","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":554785156,"identity":"d27f64d6-7d76-4d5d-b0d3-31fe947a9beb","order_by":0,"name":"Martin 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