Results 131 to 140 of about 733 (165)

Chandler wobble and geomagnetic jerks

Physics of the Earth and Planetary Interiors, 2001
Abstract Some features of the polar motion may be due to core–mantle coupling, but no convincing quantitative mechanism has yet been proposed. Considering phase jumps in the Chandler wobble and noticing their correlation with geomagnetic jerks [J. Geophys. Res.
E. Bellanger, J.-L. Le Mouël, M. Mandea, S. Labrosse   +3 more
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Localized analysis of polar geomagnetic jerks

Tectonophysics, 2013
Abstract A new method is introduced to find the relatively sudden temporal changes or jerks of the geomagnetic field over the polar regions. Geomagnetic jerk events during the 20th century have mostly been identified from direct measurements at mid-latitude geomagnetic observatories.
Hyung Rae Kim, Ralph R.B. von Frese
openaire   +1 more source

Relationship between free core nutation and geomagnetic jerks

Journal of Geodesy, 2020
Recent studies have indicated a correlation between Earth’s free core nutation (FCN) and geomagnetic jerks (GMJs). However, some uncertainties still need to be resolved before their relationship can be confirmed. The variations in the amplitude and phase of the FCN result from the comprehensive influence of the surface fluid layer and core–mantle ...
Xiaoming Cui, Heping Sun, Jianqiao Xu, Jiangcun Zhou, Xiaodong Chen   +4 more
openaire   +1 more source

Geomagnetic field hemispheric asymmetry and archeomagnetic jerks

Earth and Planetary Science Letters, 2009
Abstract We investigate the origin of the so-called archeomagnetic jerks detected in the French archeomagnetic record over the past three millennia. Although only very large-scale global archeomagnetic field models are currently available, we show that the occurrence of archeomagnetic jerks is intimately linked to what we define as “most eccentric ...
Yves Gallet, Gauthier Hulot, Arnaud Chulliat, Agnès Genevey   +3 more
openaire   +1 more source

Free core nutation and geomagnetic jerks

Journal of Geodynamics, 2013
Abstract Variations in free core nutation (FCN) are associated with different processes in the Earth's fluid core and core–mantle coupling. The same processes are generally caused the variations in the geomagnetic field (GMF) particularly the geomagnetic jerks (GMJs), which are rapid changes in GMF secular variations.
openaire   +1 more source

On the geomagnetic jerk of 1969

Journal of Geophysical Research: Solid Earth, 1985
French and British scientists have published reports describing a sudden change in the geomagnetic secular acceleration which took place around 1969. They claimed that this change, called an impulse or jerk, took place in a period of a year or two and that the sources for the jerk were internal.
openaire   +1 more source

The geomagnetic jerk of 1969 and the DGRFs

Physics of the Earth and Planetary Interiors, 1987
Abstract Cubic spline fits to the DGRF/IGRF series indicate agreement with other analyses showing the 1969–1970 magnetic jerk in the h 1 2 and g 0 2 secular change coefficients, and agreement that the h 1 1 term showed no sharp change.
Delaine Thompson, Joseph C. Cain
openaire   +1 more source

More on the alleged 1970 geomagnetic jerk

Physics of the Earth and Planetary Interiors, 1985
Abstract French and United Kingdom workers have published reports describing a sudden change in the secular acceleration, called an impulse or a jerk, which took place around 1970. They claim that this change took place in a period of a year or two and that the sources of the alleged jerk are internal. An earlier paper by this author questioned their
openaire   +1 more source

Evidence for geomagnetic jerks from 1931 to 1971

Physics of the Earth and Planetary Interiors, 1985
Abstract Examination of annual mean values of the geomagnetic elements from magnetic observatories worldwide has shown that a sudden change in secular acceleration, which has been termed a jerk, took place at about 1970. Malin et al. used the set of secular variation models compiled by Hodder to provide a global description of the jerk, and attempted
D.J. Kerridge, D.R. Barraclough
openaire   +1 more source

Geomagnetic jerk extraction based on the covariance matrix

Applied Geophysics, 2019
We normalize data from 43 Chinese observatories and select data from ten Chinese observatories with most continuous records to assess the secular variations (SVs) and geomagnetic jerks by calculating the deviations between annual observed and CHAOS-6 model monthly means.
Yan Feng, Yun-Shan Jiang, Jia-Lin Gu, Fan Xu, Yi Jiang, Shuang Liu   +5 more
openaire   +1 more source