Hostname: page-component-77c89778f8-sh8wx Total loading time: 0 Render date: 2024-07-18T19:21:49.076Z Has data issue: false hasContentIssue false
  • English
  • Français

Atmospheric Effects on Earth Rotation and Polar Motion

Published online by Cambridge University Press:  03 August 2017

David A. Salstein
David A. Salstein*
Affiliation:
Atmospheric and Environmental Research, Inc., 840 Memorial Drive, Cambridge, MA 02139 USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The variability in the earth's rotation rate not due to known solid body tides is dominated on time scales of about four years and less by variations in global atmospheric angular momentum (M), as derived from the zonal wind distribution. Among features seen in the length of day (Δl.o.d.) record produced by atmospheric forcing are the strong seasonal cycle, quasi-periodic fluctuations around 40–50 days, and an interannual signal forced by a strong Pacific warming event, known as the El Niño. Momentum variations associated with these time scales arise in different latitudinal regions. Furthermore, winds in the stratosphere make a particularly important contribution to seasonal variability.

Other related topics discussed here are (i) comparisons of the M series from wind fields produced at different weather centers, (ii) the torques that dynamically link the atmosphere and earth, and (iii) longer-term non-atmospheric effects that can be seen upon removal of the atmospheric signal. An interesting application for climatological purposes is the use of historical earth rotation series as a proxy for atmospheric wind variability prior to the era of upper-air data. Lastly, results pertaining to the role of atmospheric pressure systems in exciting rapid polar motion are presented.

Type
Geophysics
Information
Symposium - International Astronomical Union , Volume 129: The Impact of VLBI on Astrophysics and Geophysics , 1988 , pp. 401 - 410
Copyright
Copyright © Reidel 1988 

References

Anderson, J.R. and Rosen, R.D., 1983: ‘The latitude-height structure of 40–50 day variations in atmospheric angular momentum.’ J. Atmos. Sci., 40, 1584–1591.2.0.CO;2>CrossRefGoogle Scholar
Barnes, R.T.H., Hide, R., White, A.A. and Wilson, C.A., 1983: ‘Atmospheric angular momentum fluctuations, length-of-day changes and polar motion.’ Proc. R. Soc. London. A387, 31–73.Google Scholar
Chao, B.F., 1984: ‘Interannual length-of-day variation with relation to the Southern Oscillation/El Niño.’ Geophys. Res. Lett., 11, 541–544 CrossRefGoogle Scholar
Dey, C.H. and Morone, L.L., 1985: ‘Evolution of the National Meteorological Center global data assimilation system: January 1982-December 1983.’ Mon. Wea. Rev., 113, 304–318.2.0.CO;2>CrossRefGoogle Scholar
Eubanks, T.M., Steppe, J.A., Dickey, J.O., Rosen, R.D. and Salstein, D.A., 1987: ‘Rapid polar motions associated with atmospheric pressure changes and oceanic response.’ Manuscript in preparation.Google Scholar
Hide, R., Birch, N.T., Morrison, L.V., Shea, D.J., and White, A.A., 1980: ‘Atmospheric angular momentum fluctuations and change in the length of the day.’ Nature, 286, 114–117.CrossRefGoogle Scholar
Hide, R., 1984: ‘Rotation of the atmospheres of the Earth and planets.’ Phil. Trans. R. Soc. Lond., A313, 107–121.Google Scholar
Lambeck, K., 1980: The Earth's Variable Rotation. Cambridge University Press, Cambridge, 449 pp.CrossRefGoogle Scholar
Langley, R.B., King, R.W., Shapiro, I.I., Rosen, R.D. and Salstein, D.A., 1981: ‘Atmospheric angular momentum and the length of day: a common fluctuation with a period near 50 days.’ Nature, 294, 730–732.CrossRefGoogle Scholar
Madden, R.A. and Julian, P.R., 1972: ‘Description of global-scale circulation cells in the tropics with a 40–50 day period.’ J. Atmos. Sci., 29, 1109–1123.2.0.CO;2>CrossRefGoogle Scholar
McCarthy, D.D. and Babcock, A.K., 1986: ‘The length of day since 1656.’ Phys. Earth and Planet. Inter., 44, 281–292.CrossRefGoogle Scholar
Morgan, P.J., King, R.W. and Shapiro, I.I., 1985: ‘Length of day and atmospheric angular momentum: a comparison for 1981–1983.’ J. Geophys. Res., 90, 12645–12652.CrossRefGoogle Scholar
Morrison, L.V., 1979: ‘Re-determination of the decade fluctuations in the rotation of the earth in the period 1861–1978.’ Geophys. J. R. astr. Soc., 58, 349–360.CrossRefGoogle Scholar
Munk, W.H. and Macdonald, G.J.F., 1960: The Rotation of the Earth. Cambridge University Press, Cambridge, 323 pp.Google Scholar
Robertson, D.S., Carter, W.E., Tapley, B.D., Schutz, B.E., Eanes, R.J., 1985: ‘Polar motion measurements: subdecimeter accuracy verified by intercomparison.’ Science. 229, 1259–1261.CrossRefGoogle ScholarPubMed
Rosen, R.D. and Salstein, D.A., 1983: ‘Variations in atmospheric angular momentum on global and regional scales and the length of day.’ J. Geophys. Res., 88, 5451–5470.CrossRefGoogle Scholar
Rosen, R.D. and Salstein, D.A., 1985: ‘Contribution of stratospheric winds to annual and semiannual fluctuations in atmospheric angular momentum and the length of day.’ J. Geophys. Res., 90, 8033–8041.CrossRefGoogle Scholar
Rosen, R.D., Salstein, D.A., Miller, A.J. and Arpe, K., 1987: ‘Accuracy of atmospheric angular momentum estimates from operational analyses.’ Mon. Wea. Rev., 115, in press.2.0.CO;2>CrossRefGoogle Scholar
Rosen, R.D., Salstein, D.A., Eubanks, T.M., Dickey, J.O. and Steppe, J.A., 1984: ‘An El Niño signal in atmospheric angular momentum and earth rotation.’ Science. 225, 411–414.CrossRefGoogle Scholar
Salstein, D.A. and Rosen, R.D., 1986: ‘Earth rotation as a proxy for interannual variability in atmospheric circulation, 1860-present.’ J. Climate Appl. Meteor., 25, 1870–1877.2.0.CO;2>CrossRefGoogle Scholar
Salstein, D.A. and Rosen, R.D., 1987: ‘Regional contributions to the atmospheric excitation of rapid polar motions,’ manuscript in preparation.Google Scholar
Swinbank, R., 1985: ‘The global atmospheric angular momentum balance inferred from analyses made during the FGGE.’ Quart. J. R. Met. Soc., 111, 977–992.CrossRefGoogle Scholar
van Loon, H. and Shea, D.J., 1985: ‘The Southern Oscillation. Part IV: The precursors south of 15°S to the extremes of the oscillation.’ Mon. Wea Rev., 113, 2063–2074.2.0.CO;2>CrossRefGoogle Scholar
Wahr, J.M. and Oort, A.H., 1984: ‘Friction- and mountain-torque estimates from global atmospheric data.’ J. Atmos. Sci., 41, 190–204.2.0.CO;2>CrossRefGoogle Scholar
Wolf, W.L. and Smith, R.B., 1987: ‘Length of day changes and mountain torque during El Niño.’ J. Atmos. Sci., in press.2.0.CO;2>CrossRefGoogle Scholar