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10th Generation International Geomagnetic Reference Field [PDF]

Eos, Transactions American Geophysical Union, 2005
The International Association of Geomagnetism and Aeronomy (IAGA) released the 10th Generation International Geomagnetic Reference Field (IGRF) on 12 December 2004. This is the latest version of a standard mathematical description of the Earth's main magnetic field, and is used widely in studies of the Earth's deep interior, crust, ionosphere, and ...
Stefan Maus, Susan MacMillan
openaire   +1 more source

Bidirectional Energy Transfer via Simultaneous Wave‐Particle Resonances in Inhomogeneous Space Plasmas

AGU Advances, Volume 7, Issue 4, August 2026.
Abstract Wave‐particle resonance is a key mechanism for energy transfer in collisionless plasmas with important implications for wave excitation and particle acceleration. Cyclotron resonance occurs when a particle's gyromotion synchronizes with the wave fields, with their interactions usually describable by quasilinear diffusion or nonlinear trapping.
Jing‐Huan Li, Xu‐Zhi Zhou, Shan Wang, Zhi‐Yang Liu, Yuri V. Khotyaintsev, Daniel B. Graham, Qiu‐Gang Zong, Chao Yue, Anton V. Artemyev, Yoshiharu Omura, Si Liu, Li Li, Jie Ren, Zi‐Kang Xie, Yun Yan   +14 more
wiley   +1 more source

Evaluation of candidate models for the 14th generation International Geomagnetic Reference Field

Earth, Planets and Space
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).
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   +30 more
doaj   +1 more source

Kamafugite Magma Pathways and Lava‐Flow Paleotopography From Three‐Dimensional Audiomagnetotelluric Imaging Constrained by Borehole Data

Earth and Space Science, Volume 13, Issue 8, August 2026.
Abstract An audiomagnetotelluric (AMT) survey was conducted within the Alto Paranaíba Igneous Province, southeastern Brazil, to delineate shallow occurrences of kamafugite, a rare ultrapotassic volcanic rock worldwide. A dense grid of AMT stations was deployed, allowing the construction of a high‐resolution 3D electrical resistivity model ...
Lucca M. Franco, Emanuele F. La Terra, Liliane P. Panetto, Adevilson O. Alves, Miguel A. Tupinambá, Sergio L. Fontes, Emin U. Ulugergerli   +6 more
wiley   +1 more source

A Contrasting TEC Behavior Over the Low‐Latitude Post‐Midnight Sector During Recovery Phases of May and October 2024 Storms: Possible Role of PPEF, DDEF, and O/N2

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract The present study reports on the variability of the post‐midnight ionosphere over the low‐latitude sector during the recovery phases of the May and October 2024 storms. Multi‐instrument observations, comprising global navigation satellite system total electron content (TEC), F‐layer peak height, electron density profiles, and column O/N2 ...
Rahul Rathi, Akash Kumar, Alok Kumar Ranjan, Dipjyoti Patgiri, Satarupa Chakrabarti, Lot Ram   +5 more
wiley   +1 more source

Candidate geomagnetic field models for IGRF-14 and secular acceleration since 2020

Earth, Planets and Space
IGRF-14 is the fourteenth generation of the International Geomagnetic Reference Field (IGRF), a spherical harmonic model of Earth’s main magnetic field and its secular variation, developed through international collaboration under the auspices of the ...
Arnaud Chulliat, Manoj Nair, Sam Califf
doaj   +1 more source

Longitudinal Variation of Ionospheric Irregularities and Response of the Ionosphere During 10–13 May and 10–13 October 2024 Geomagnetic Storms

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract We examine the response of the ionosphere to the 10–13 May 2024 and 10–13 October 2024 geomagnetic storms, the two recent great geomagnetic storms of solar cycle 25. We identified the occurrence of ionospheric irregularities during the two geomagnetic storms.
Valence Habyarimana, Mark B. Moldwin, John Bosco Habarulema, Sharon Aol, Jean Claude Uwamahoro, Teshome Dugassa, Daniel Okoh, Solomon Otoo Lomotey   +7 more
wiley   +1 more source

Peculiar Magnetosphere‐Atmosphere Coupling and Its Impacts Over the South American Magnetic Anomaly Region

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract The auroral‐like sporadic E‐layer is typically observed at altitudes between 100 and 150 km within the South American Magnetic Anomaly region. However, the occurrence of an unusual layer event detected above this altitude range on 18 July 2017 has raised intriguing questions regarding the physical processes responsible for the substantial ...
Lígia A. Da Silva, Hui Li, Laysa C. A. Resende, Vânia F. Andrioli, Angela M. Santos, Juliano Moro, Paulo R. Jauer, Luis Eduardo Vieira, Lívia R. Alves, José Paulo Marchezi, Jiankui Shi, Jiyao Xu, Paulo P. Batista, Jose V. Bageston, Yajun Zhu, Clezio M. Denardini, Chi Wang, Ezequiel Echer, Guotao Yang, Alexandre A. Pimenta, Joaquim R. Costa, Zhengkuan Liu   +21 more
wiley   +1 more source

Assessing GNSS Reflectometry for High‐Latitude 3D Ionospheric Imaging

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract This study investigates whether Global Navigation Satellite System Reflectometry (GNSS‐R) measurements from low‐Earth‐orbit (LEO) satellites can improve three‐dimensional (3D) ionospheric electron density imaging, with a focus on high‐latitude regions. Conventional ionospheric tomography is limited by sparse ground‐based receiver coverage over
Brenna Royersmith, Brian Breitsch, Jade Y. Morton   +2 more
wiley   +1 more source

International Geomagnetic Reference Field: The Sixth Generation.

Journal of geomagnetism and geoelectricity, 1992
In August 1991 the International Association of Geomagnetism and Aeronomy revised the International Geomagnetic Reference Field (IGRF) for the fifth time. This Sixth Generation IGRF now consists of 10 spherical harmonic models of the main geomagnetic field at five year intervals from 1945 through 1990 and a secular variation model extending the main ...
openaire   +3 more sources