Long-term electromagnetic core–mantle coupling and the Earth’s rotation acceleration in the Mesozoic Era

Occultations of stars by the Moon, and solar and lunar eclipses are analysed for variations in the Earth’s rotation over the past 2700 years. Although tidal braking provides the dominant, long-term torque, it is found that the rate of rotation does not decrease uniformly as would be expected if tidal friction were the only mechanism affecting the Earth’s rotation. There are also non-tidal changes present that vary on timescales ranging from decades to millennia. The magnitudinal and temporal behaviour of these non-tidal variations are evaluated in this paper.

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On the Reduction in Tidal Dissipation Produced by Increases in the Earth’s Rotation Rate and Its Effect on the Long-Term History of the Moon’s Orbit

Tidal Friction and the Earth’s Rotation II ◽

10.1007/978-3-642-68836-2_14 ◽

1982 ◽

pp. 210-221 ◽

Cited By ~ 5

Author(s):

D. J. Webb

Keyword(s):

Rotation Rate ◽

Earth’S Rotation ◽

Earth's Rotation ◽

Tidal Dissipation ◽

History Of

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Long-term fluctuations in the Earth’s rotation: 700 BC to AD 1990

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1995.0028 ◽

1995 ◽

Vol 351 (1695) ◽

pp. 165-202 ◽

Cited By ~ 117

Keyword(s):

High Precision ◽

Arab World ◽

Earth’S Rotation ◽

Precision Data ◽

Earth's Rotation ◽

High Precision Data ◽

Answering Questions

Records of solar and lunar eclipses in the period 700 BC to AD 1600, originating from the ancient and medieval civilizations of Babylon, China, Europe and the Arab world, are amassed and critically appraised for their usefulness in answering questions about the long-term variability of the Earth’s rate of rotation. Results from previous analyses of lunar occupations in the period AD 1600-1955.5, and from high-precision data in AD 1955.5-1990, are included in the dataset considered in this paper.

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Comparisons of ET(solar), ET(lunar), UT, and TDT

Symposium - International Astronomical Union ◽

10.1017/s0074180900119825 ◽

1988 ◽

Vol 128 ◽

pp. 413-418

Author(s):

Wm. Markowitz

Keyword(s):

Earth’S Rotation ◽

Meridian Circle ◽

Earth's Rotation ◽

Term Fluctuation

SummaryA fundamental dynamical scale, ET(solar), was formed from absolute, meridian circle observations, from 1835 to 1982. At 1967.0 the ET(solar) and SI seconds were equal to 1 part in 109 and, from Morrison's (1979 a) ET(lunar) scale, the ET(ILE) and SI seconds were equal to 1 part in 1010. The long term fluctuation in the Earth's rotation has been parabolic, instead of sinusoidal, for at least 350 y.

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Long-term variations in the angular velocity of Earth’s rotation

Doklady Physics ◽

10.1134/1.1881720 ◽

2005 ◽

Vol 50 (2) ◽

pp. 95-99

Author(s):

G. G. Denisov ◽

V. V. Novikov ◽

A. E. Fedorov

Keyword(s):

Angular Velocity ◽

Earth’S Rotation ◽

Earth's Rotation ◽

Long Term Variations

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Zonal and tesseral harmonic perturbations of an artificial satellite

Symposium - International Astronomical Union ◽

10.1017/s0074180900105625 ◽

1966 ◽

Vol 25 ◽

pp. 323-325 ◽

Cited By ~ 1

Author(s):

B. Garfinkel

Keyword(s):

Angular Velocity ◽

Spherical Harmonics ◽

Artificial Satellite ◽

Compact Form ◽

Earth’S Rotation ◽

Earth's Rotation ◽

Secular Variations ◽

Tesseral Harmonics

The paper extends the known solution of the Main Problem to include the effects of the higher spherical harmonics of the geopotential. The von Zeipel method is used to calculate the secular variations of orderJmand the long-periodic variations of ordersJm/J2andnJm,λ/ω. HereJmandJm,λare the coefficients of the zonal and the tesseral harmonics respectively, withJm,0=Jm, andωis the angular velocity of the Earth's rotation. With the aid of the theory of spherical harmonics the results are expressed in a most compact form.

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