Zobrazeno 1 - 10
of 174
pro vyhledávání: '"FINLAY, CHRISTOPHER C."'
Tidal flow of seawater across the Earth's magnetic field induces electric currents and magnetic fields within the ocean and solid Earth. The amplitude and phase of the induced fields depends on electrical properties of both the seawater and the solid
Externí odkaz:
http://arxiv.org/abs/2404.03504
Publikováno v:
Geophysical Journal International, Volume 236, Issue 3, March 2024, Pages 1646-1667
Satellite observations of the geomagnetic field contain signals generated in Earth's interior by electrical currents in the core and by magnetized rocks in the lithosphere. At short wavelengths the lithospheric signal dominates, obscuring the signal
Externí odkaz:
http://arxiv.org/abs/2402.02270
Autor:
Barrois, Olivier, Hammer, Magnus D., Finlay, Christopher C., Martin, Yannick, Gillet, Nicolas
Publikováno v:
GJI, 2018, 215, 695-712
We jointly invert for magnetic and velocity fields at the core surface over the period 1997-2017, directly using ground-based observatory time series and measurements from the CHAMP and Swarm satellites. Satellite data are reduced to the form of virt
Externí odkaz:
http://arxiv.org/abs/2312.09878
Publikováno v:
GJI, 2022, 231, 129-158
We present investigations of rapidly-rotating convection in a thick spherical shell geometry relevant to planetary cores, comparing results from Quasi-Geostrophic, 3D and hybrid QG-3D models. The 170 reported calculations span Ekman numbers, $Ek$, be
Externí odkaz:
http://arxiv.org/abs/2312.09826
We present dynamos computed using a hybrid QG-3D numerical scheme in a thick spherical shell geometry. Our model is based on a quasi-geostrophic convection code extended with a 3D treatment of heat transport and magnetic induction. We find a collecti
Externí odkaz:
http://arxiv.org/abs/2312.09946
Publikováno v:
Geophysical Journal International, Volume 235, Issue 2, November 2023, Pages 1736-1760
Estimating high resolution models of the Earth's core magnetic field and its time variation in the polar regions requires that one can adequately account for magnetic signals produced by polar ionospheric currents, which vary on a wide range of time
Externí odkaz:
http://arxiv.org/abs/2309.04286
We present a method for obtaining efficient probabilistic solutions to geostatistical and linear inverse problems in spherical geometry. Our Spherical Direct Sequential Simulation (SDSSIM) framework combines information from possibly noisy observatio
Externí odkaz:
http://arxiv.org/abs/2204.03404
Publikováno v:
Geophys. J. Int. (2022) 229, 2096-2114
We present local time-series of the magnetic field gradient tensor elements at satellite altitude derived using a Geomagnetic Virtual Observatory (GVO) approach. Gradient element timeseries are computed in 4-monthly bins on an approximately equal-are
Externí odkaz:
http://arxiv.org/abs/2204.00258
Publikováno v:
Planets and Space (2021) 73:73
We use 20 years of magnetic field measurements from the Oersted, CHAMP and Swarm satellite missions, supplemented by calibrated platform magnetometer data from the CryoSat2 satellite, to study time variations of the Earth's core field at satellite al
Externí odkaz:
http://arxiv.org/abs/2111.14538
Publikováno v:
Earth, Planets and Space volume 73, Article number: 23 (2021)
Models of the geomagnetic field rely on magnetic data of high spatial and temporal resolution. The magnetic data from low-Earth orbit satellites of dedicated magnetic survey missions such as CHAMP and Swarm play a key role in the construction of such
Externí odkaz:
http://arxiv.org/abs/2103.09078