Results 21 to 30 of about 657 (236)
A Model of the Geomagnetic Field at Epoch 1975 [PDF]
Geophysical Journal International, 1975 Summary The main magnetic field at epoch 1975 is defined by 168 spherical harmonic coefficients (those representing the internal part to degree and order 12). A further 80 coefficients (degree and order 8) define the secular variation and, in addition, 26 secular acceleration coefficients (those most significantly determined) are included.
D. R. Barraclough +3 more
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Data Science Journal, 2011 There is a need to develop secular variation (SV) models using satellite data as the use of ground data is not always possible. Ground data has many limitations including limited data points and lack of data over ocean areas that are not easily ...
E Nahayo, P B Kotzé, M J Alport
doaj +1 more source
Tectonic process monitoring by variations of the geomagnetic field absolute intensity
Annals of Geophysics, 1997 We propose a novel technique for tectonic process monitoring. The technique includes: measurements of absolute intensity variations, at network sites, synchronously with measurements of horizontal geomagnetic field variations at a reference site ...
O. V. Pankratov +2 more
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Measuring Information Coupling between the Solar Wind and the Magnetosphere–Ionosphere System
Entropy, 2020 The interaction between the solar wind and the Earth’s magnetosphere−ionosphere system is very complex, being essentially the result of the interplay between an external driver, the solar wind, and internal processes to the magnetosphere ...
Mirko Stumpo +3 more
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Nowcasting geoelectric fields in Ireland using magnetotelluric transfer functions
Journal of Space Weather and Space Climate, 2023 Geomagnetically induced currents (GIC) driven by geoelectric fields pose a hazard to ground-based infrastructure, such as power grids and pipelines. Here, a new method is presented for modelling geoelectric fields in near real time, to provide valuable ...
Malone-Leigh John +5 more
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Applying inversion techniques to derive source currents and geoelectric fields for geomagnetically induced current calculations [PDF]
Annales Geophysicae, 2014 This research focuses on the inversion of geomagnetic variation field measurement to obtain source currents in the ionosphere. During a geomagnetic disturbance, the ionospheric currents create magnetic field variations that induce geoelectric fields ...
J. S. de Villiers, P. J. Cilliers
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Regional geomagnetic field modelling: the contribution of the Istituto Nazionale di Geofisica
Annals of Geophysics, 1997 Models of the geomagnetic field are mathematical expressions able to represent the Earth's magnetic field space and time variations. Time variations on the long term basis are represented by the so-called secular variation.
A. Meloni +3 more
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Sequential modelling of the Earth’s core magnetic field
Earth, Planets and Space, 2020 We describe a new, original approach to the modelling of the Earth’s magnetic field. The overall objective of this study is to reliably render fast variations of the core field and its secular variation.
Guillaume Ropp +3 more
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Physics-based secular variation candidate models for the IGRF
Earth, Planets and Space, 2021 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 field ...
Alexandre Fournier +3 more
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Modelling geomagnetically induced currents in midlatitude Central Europe using a thin-sheet approach [PDF]
Annales Geophysicae, 2017 Geomagnetically induced currents (GICs) in power systems, which can lead to transformer damage over the short and the long term, are a result of space weather events and geomagnetic variations.
R. L. Bailey +8 more
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