Physics-based secular variation candidate models for the IGRF

Autor: Alexandre Fournier, Julien Aubert, Vincent Lesur, Erwan Thébault

Publikováno v: Earth, Planets and Space, Vol 73, Iss 1, Pp 1-18 (2021)

Abstract Each International Geomagnetic Reference Field (IGRF) model released under the auspices of the International Association of Geomagnetism and Aeronomy comprises a secular variation component that describes the evolution of the main magnetic f

Externí odkaz: https://doaj.org/article/db7bc9965c95461db3f3929c4722bb54

Gyre-driven decay of the Earth’s magnetic dipole

Autor: Christopher C. Finlay, Julien Aubert, Nicolas Gillet

Publikováno v: Nature Communications, Vol 7, Iss 1, Pp 1-8 (2016)

The magnitude of the Earth’s magnetic dipole has decreased by 9% over the past 175 years. Here, the authors suggest that the rate of dipole decay is controlled by a huge gyre in the liquid metal outer core acting on a field asymmetry, and that deca

Externí odkaz: https://doaj.org/article/c3bf34e965a44e48bd7595263a381a20

An ensemble Kalman filter for the time‐dependent analysis of the geomagnetic field

Autor: Alexandre Fournier, Lars Nerger, Julien Aubert

Publikováno v: Geochemistry, Geophysics, Geosystems, Vol 14, Iss 10, Pp 4035-4043 (2013)

We present the application of the ensemble Kalman filter to a three‐dimensional, convection‐driven model of the geodynamo. Our implementation rests on a suitably modified version of the parallel data assimilation framework of Nerger and Hiller (2

Externí odkaz: https://doaj.org/article/535f7451fc6f49288141af48d8298930

A taxonomy of simulated geomagnetic jerks

Autor: Julien Aubert, Philip W Livermore, Christopher C Finlay, Alexandre Fournier, Nicolas Gillet

Publikováno v: Geophysical Journal International
Geophysical Journal International, 2022, 231 (1), pp.650-672. ⟨10.1093/gji/ggac212⟩
Aubert, J, Livermore, P W, Finlay, C C, Fournier, A & Gillet, N 2022, ' A taxonomy of simulated geomagnetic jerks ', Geophysical Journal International, vol. 231, no. 1, pp. 650-672 . https://doi.org/10.1093/gji/ggac212
XXVIII General Assembly of the International Union of Geodesy and Geophysics (IUGG)

Geomagnetic jerks - abrupt changes in the acceleration of Earth's magnetic field that punctuate geomagnetic records - have been richly documented over the past decades by taking advantage of the complementary strengths of ground observatory and satel

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::830c38f23704d239fcb825cb56245776
https://cnrs.hal.science/hal-03719369/document

A reduced stochastic model of core surface dynamics based on geodynamo simulations

Autor: Loïc Huder, Nicolas Gillet, Julien Aubert

Publikováno v: Geophysical Journal International
Geophysical Journal International, Oxford University Press (OUP), In press, ⟨10.1093/gji/ggz313⟩
Geophysical Journal International, In press, ⟨10.1093/gji/ggz313⟩

SUMMARYWe make use of recent geodynamo simulations to propose a reduced stochastic model of the dynamics at the surface of Earth’s core. On decadal and longer periods, this model replicates the most energetic eigen directions of the geodynamo compu

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::31f41cad1d12afb05cc1a478ce3b2b73
https://doi.org/10.1093/gji/ggz313