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Analysis of Long Time Series of Polar Motion

Published online by Cambridge University Press:  12 April 2016

H. Schuh ,
B. Richter  and
S. Nagel
H. Schuh
Affiliation:
Deutsches Geodätisches Forschungsinstitut (DGFI)Marstallplatz 8, 80539 München, Germanye-mail:[email protected]
B. Richter
Affiliation:
Deutsches Geodätisches Forschungsinstitut (DGFI)Marstallplatz 8, 80539 München, Germanye-mail:[email protected]
S. Nagel
Affiliation:
Deutsches Geodätisches Forschungsinstitut (DGFI)Marstallplatz 8, 80539 München, Germanye-mail:[email protected]

Abstract

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Two long time series of polar motion were analysed with respect to a linear drift, decadal variations, Chandler wobble and annual wobble: the C01 series published by the International Earth Rotation Service (IERS) and the pole series which J. Vondrák, obtained by re-analysis of the classical astronomical observations using the HIPPARCOS reference frame (1899.7–1992.0). By a least-squares fit the linear drift of the pole, usually called ‘secular polar motion,’ was determined to 3.31 milliarcseconds/year (mas/yr) toward 76.1° West longitude. For this fit the a priori correlations within each pair of pole coordinates were taken into account, and the weighting function was calculated by estimation of empirical variance components. The decadal variations of the pole path were determined by Fourier analysis. Using a sliding window analysis, the variability of the periods, the amplitudes and the phases of the Chandler wobble and annual wobble was investigated. The variances of the results and the number of iterations needed to get a convergence in the nonlinear approach show that the new time series by Vondrák is more homogeneous and consistent than the IERS C01 series.

Type
Part 3. Observational Techniques for Polar Motion
Information
International Astronomical Union Colloquium , Volume 178: Polar Motion: Historical and Scientific Problems , 2000 , pp. 321 - 332
Copyright
Copyright © Astronomical Society of the Pacific 2000

References

Chandler, S.C., 1891, On the variation of latitude, Astron. J., 248, 59–61.Google Scholar
Eubanks, T.M., 1993, Variation in the orientation of the Earth, Contributions of Space Geodesy to Geodynamics: Earth Dynamics, ed. by Smith, D.E. and Turcotte, D.L., AGU Geodynamics Series, 24, 1–54.Google Scholar
Greiner-Mai, H., 1993, Decade Variations of the Earth’s Rotation and Geomagnetic Core-Mantle Coupling, J. Geomag. Geoelectr., 45, 1333–1345.CrossRefGoogle Scholar
Greiner-Mai, H., Jochmann, H., and Barthelmes, F., 1999, Influence of possible inner-core motions on the polar motion and the gravity field, Phys. Earth Planet. Inter., 117, 81–93.CrossRefGoogle Scholar
Gross, R.S. and Vondrák, J., 1999, Astrometrie and space-geodetic observations of polar wander, Geophys. Res. Lett. 26, 2085–2088.Google Scholar
Jochmann, H., 1993, Earth Rotation and Global Change, Adv. Space Res., 13, 271–280.Google Scholar
Hide, R., 1995, The topographique torque on a bounding surface of a rotating gravitating fluid and the excitation by core motions of decadal fluctuations in the Earth’s rotation, Geophys. Research Letters, 22, 961–964.CrossRefGoogle Scholar
Korsun, A.A. and Yatskiv, Ya.S., 1999, Comments on slow latitude variations and secular motion of the Earth’s pole, Journées 1998, Syst. de Réf. Spatio-Temporels, Paris, ed. by Capitaine, N., Obs. de Paris, UMR 8630/CNRS, 223–227.Google Scholar
Küstner, F., 1888, Neue Methode zur Bestimmung der Aberrations-Constante nebst Untersuchungen über die Veränderlichkeit der Polhöhe, Beobachtungs-Ergebnisse der Königlichen Sternwarte zu Berlin, 3, 1–59.Google Scholar
McCarthy, D.D., and Luzum, B.J., 1996, Path of the mean rotational pole from 1899 to 1994, Geophys. J. Int., 125, 623–629.Google Scholar
Vicente, R.O., and Wilson, C.R., 1997, On the variability of the Chandler frequency, Journ. Geophys. Res., 102, 20439–20445.CrossRefGoogle Scholar
Vondrák, J., 1999, Earth rotation parameters 1899.7-1992.0 after reanalysis within the HIPPARCOS frame, Surveys in Geophysics, 20, 169–195.Google Scholar
Vondrák, J., 2000, Survey of Observational Techniques and HIPPARCOS Re-analysis, this issue.CrossRefGoogle Scholar