Results 21 to 30 of about 143 (124)

Earth orientation and its excitations by atmosphere, oceans, and geomagnetic jerks [PDF]

Serbian Astronomical Journal, 2015
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.
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Worldwide wavelet analysis of geomagnetic jerks [PDF]

Journal of Geophysical Research: Solid Earth, 1996
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, Gibert, Dominique, Hulot, Gauthier, Le Mouël, Jean-Louis, Saracco, Ginette   +4 more
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Interplanetary external driven quasidynamo as the origin of geomagnetic jerks correlated with length of day and gravity anomaly

Contributions to Geophysics and Geodesy, 2018
We report phenomenological inevitable correlation between the Sun’s magnetic field oscillation through the Earth and the Jupiter, with sinusoidal geomagnetic jerks observed at the Earth, additionally aligned with the gravity and length of day sinusoidal ...
Mohsen LUTEPHY
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Semi‐decadal and decadal signals in atmospheric excitation of length‐of‐day

Earth and Space Science, 2020
At timescales shorter than about 2~yr, non‐tidal length‐of‐day (LOD) variations are mainly excited by angular momentum exchanges between the atmospheric, oceanic and continental hydrological fluid envelopes and the underlying solid Earth.
Nan Yu., Gang Chen, Jim Ray, Wei Chen, Nengfang Chao   +4 more
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A global analysis of the 1991 geomagnetic jerk [PDF]

Geophysical Journal International, 2000
Summary A recent examination of the geomagnetic annual mean values for the European magnetic observatories has shown the existence of a sudden change in the secular acceleration in about 1991 (Cafarella & Meloni 1995; Macmillan 1996). Using first differences of the Y (east geomagnetic field component) mean values from 74 observatories, the worldwide
De Michelis, P., Cafarella, L., Meloni, A.   +2 more
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Rescue, integration, and analytical application of historical data from eight pioneering geomagnetic observatories in China [PDF]

Earth System Science Data
Decades to centuries of continuous geomagnetic observation data have extensive scientific research and practical application value, especially in revealing the long-term variation of the geomagnetic field, which is irreplaceable. During the International
S. Zhang, C. Fu, J. Wang, C. Chen, G. Zhu, Q. Zhao, J. Chen, S. He, B. Wang, P. Guo, N. Deng, J. Lu, H. Yu   +12 more
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Strong earthquakes and geomagnetic jerks: a cause-effect relationship?

Annals of Geophysics, 1995
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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A regional geomagnetic field model over Southern Africa derived with harmonic splines from Swarm satellite and ground-based data recorded between 2014 and 2019

Earth, Planets and Space, 2022
A regional harmonic spline geomagnetic main field model, Southern Africa Core Field Model (SACFM-3), is derived from Swarm satellite and ground-based data for the southern African region, in the eastern part of the South Atlantic Anomaly (SAA) where the ...
Emmanuel Nahayo, Monika Korte
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Worldwide character of the 1991 geomagnetic jerk [PDF]

Geophysical Research Letters, 1998
A recent examination of the geomagnetic element annual mean values for the European magnetic observatories, has shown the existence of a sudden change in the secular acceleration at about 1991. In this work the space time character of the 1991 impulse is investigated and its worldwide character is evidenced; an evaluation of the amplitude spatial ...
De Michelis, P., Cafarella, L., Meloni, A.   +2 more
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Local time features of geomagnetic jerks [PDF]

Earth, Planets and Space, 2014
The geomagnetic jerk amplitudes, which are defined as abruptness of changes in the trends of geomagnetic time series, are investigated with geomagnetic monthly means computed from hourly mean values at each local time. A statistical time series model in which the trend component is expressed by a second order spline function with variable knots is ...
Nagao, Hiromichi, Iyemori, Toshihiko, Higuchi, Tomoyuki, Nakano, Shin’ya, Araki, Tohru   +4 more
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