Results 21 to 30 of about 323 (143)
On the characteristics of successive geomagnetic jerks [PDF]
Spherical harmonic models of the 1969, 1979 and 1992 geomagnetic jerks are computed using data from about 160 worldwide geomagnetic observatories. The dominance of the internal origin part with respect to the external one confirms again the internal origin of these events. A change of sign is observed between two successive jerks (1969–1979, 1979–1992).
Le Huy, Minh +3 more
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Evidence for geomagnetic jerks in comprehensive models [PDF]
Abstract The rate of secular variation occasionally undergoes a sudden, sharp change, called a geomagnetic jerk. Such jerks have been detected in geomagnetic time series, centered—over the last four decades—around 1971, 1980, 1991, and 1999; others have been inferred from historical records. The geomagnetic jerks represent a reorganization of
Chambodut, A., Mandea, M.
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IGRF-14 secular variation prediction from core surface flow acceleration [PDF]
The International Geomagnetic Reference Field (IGRF) has been regularly updated since its inception in 1965. Every recent iteration contains an estimate of the geomagnetic secular variation (SV), for the intermediate years between iterations. We submit a
Frederik Dahl Madsen +5 more
doaj +2 more sources
Strong earthquakes and geomagnetic jerks: a cause-effect relationship?
Secular variation of the geomagnetic field observed at the Earth's surface has been found to undergo impulsive accelerations Gerks) lasting less than a few years. In this paper the relations between jerks and the occurrence of strong earthquakes (Ms ?
L. Alfonsi, F. Florindo
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Worldwide wavelet analysis of geomagnetic jerks [PDF]
Following an earlier study which gives the principles of the method and an example of application to the eastern component of the magnetic field in the European region [Alexandrescu et al., 1995], detection and characterization of geomagnetic jerks using wavelet analysis is generalized to any horizontal component of the field and to a worldwide ...
Alexandrescu, Mioara +4 more
openaire +4 more sources
Detection of geomagnetic jerks using wavelet analysis [PDF]
Wavelet analysis is applied to detect and characterize singular events, or singularities, or jerks, in the time series made of the last century monthly mean values of the east component of the geomagnetic field from European observatories. After choosing a well‐adapted wavelet function, the analysis is first performed on synthetic series including an ...
Alexandrescu, Mioara +4 more
openaire +4 more sources
Earth orientation and its excitations by atmosphere, oceans, and geomagnetic jerks [PDF]
In addition to torques exerted by the Moon, Sun, and planets, changes of the Earth orientation parameters (EOP) are known to be caused also by excitations by the atmosphere and oceans.
Vondrák J., Ron C.
doaj +2 more sources
Geomagnetic jerks from the Earth’s surface to the top of the core [PDF]
Abstract Rapid changes in the magnetic field characterised by an abrupt change in the secular variation have been named “secular variation impulses” or “geomagnetic jerks”. Three of these events, around 1968, 1978 and 1990, occurred during the time-span covered by the comprehensive model CM4 (Sabaka et al., 2002, 2004).
Chambodut, Aude +2 more
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The period and quality factor of the Chandler wobble (CW) are useful for constraining the Earth's internal structure properties, such as the mantle elasticity.
Yachong An, Hao Ding
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Versus the theory of fully stochastically mechanism of geomagnetic jerks based on the buoyant force driven Quasi-Geostrophic (QG) dynamo, the torsional waves in realistic condition of the Earth's core evolve in the intradecadal time scales.
Mohsen LUTEPHY +2 more
doaj +1 more source

