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More on the alleged 1970 geomagnetic jerk
Physics of the Earth and Planetary Interiors, 1985Abstract 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
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Was the 1970 geomagnetic jerk of internal or external origin?
Nature, 1982Annual mean data from worldwide magnetic observatories show that there was a jerk1 (step-change in the second time derivative) in the geomagnetic field, which took place over an interval of
S. R. C. Malin, B. M. Hodder
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A geomagnetic jerk for the early 1990's
Earth and Planetary Science Letters, 1996Abstract Records from geomagnetic observatories in Europe are showing indications of another impulse in the third time derivative of the east component around 1991. These impulses, otherwise known as jerks, have occurred in the past at about 1925, 1969 and 1978 and possibly also 1900 and 1913.
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Geomagnetic field hemispheric asymmetry and archeomagnetic jerks
Earth and Planetary Science Letters, 2009Abstract 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 +3 more
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A discussion of impulses and jerks in the geomagnetic field
Journal of Geophysical Research: Solid Earth, 1984French and United Kingdom workers have published reports describing a sudden change in the secular acceleration, called an impulse or a jerk, which took place in 1969. They claim that this change took place in a period of a year or two and that the sources for the alleged jerk are internal.
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Geomagnetic jerk extraction based on the covariance matrix
Applied Geophysics, 2019We 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 +5 more
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Evidence for geomagnetic jerks from 1931 to 1971
Physics of the Earth and Planetary Interiors, 1985Abstract 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
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On external and internal parts of the geomagnetic jerk of 1970
Physics of the Earth and Planetary Interiors, 1985This paper is a short contribution to the debate on sources (external or internal) of the geomagnetic acceleration phenomenon (jerk) around 1970. Using annual means of very quiet days it is shown here that the external part in the jerk signal in Ydot in North Europe was rather small.
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Wavelet analysis of geomagnetic jerks
2014Geomagnetic jerks, or secular variation impulses, are abrupt changes in the slope of the first time derivative of the Earth's magnetic field. These changes occur on time scales of the order of a year. It has been demonstrated that the jerks might be more singular than previously supposed; their """"regularity"""" is closer to 1.5 than to 2.
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