Fluctuations in the Earth's rotation and the topography of the core-mantle interface

@article{Hide1989FluctuationsIT,
  title={Fluctuations in the Earth's rotation and the topography of the core-mantle interface},
  author={Raymond Hide},
  journal={Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences},
  year={1989},
  volume={328},
  pages={351 - 363}
}
  • R. Hide
  • Published 4 July 1989
  • Physics
  • Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
As arguments in favour of the notion that very slow convection in the highly viscous mantle is confined to the upper 700 km gradually weakened over the past 20 years, so geophysicists have increased their willingness to entertain the idea that significant horizontal variations in temperature and other structural parameters occur at all levels in the lower mantle. Concomitant density variations, including those caused by distortions in the shape of the core-mantle interface, would contribute… 
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References

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  • Physics
    Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
  • 1982
Evidence for the presence of undulations or temperature variations, or both, at the core-mantle boundary comes from the remarkably high correlation between the pattern of long-wavelength
Westward drift, core motions and exchanges of angular momentum between core and mantle
The westward drift is one of the most well known features of the geomagnetic field. In this paper we come back to the apparent drift of the main field as seen at the Earth's surface, and show that
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HORIZONTAL stresses at the interface where the liquid core of the Earth meets the surrounding solid mantle prevent these two major regions of the Earth from moving independently of one another.
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Summary. Previous studies, both geomagnetic and seismic, have been unable to show conclusively whether or not there is fluid upwelling at the core-mantle boundary. Here a new method is developed, in
On the excitation of short-term variations in the length of the day and polar motion
Variations in the distribution of mass within the atmosphere, and changes in the pattern of winds produce fluctuations in all three components of the angular momentum of the atmosphere on time-scales
On the effects of a bumpy core-mantle interface
Abstract Motivated by the high degree of correlation between the variable parts of the magnetic and gravitational potentials of the Earth discovered by Hide and Malin (using a harmonic analysis
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The westward drift of the non-dipole part of the earth’s magnetic field and of its secular variation is investigated for the period 1907-45 and the uncertainty of the results discussed. It is found
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Maps of the magnetic field at the core–mantle boundary for 1715–1980 reveal static features in the field and an absence of westward drift from much of the core–mantle boundary. The static features
Time Variations of the Earth's Magnetic Field: From Daily to Secular
Variations in time of the Earth's natural magnetic field have a frightfully wide spectrum, ranging over more than 20 orders of magnitude: They extend from well over 103 Hz, where they merge into the
Electromagnetic Core-Mantle Coupling
The time-scale of the variation in the length of the day is comparable to, or shorter than, the electromagnetic decay time, τη, of the mantle. This suggests that an electromagnetic theory for the
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