EarthRef.org Reference Database (ERR)
Development and Maintenance by the EarthRef.org Database Team

Detailed Reference Information
Chao et al. 1996
Chao, B.F., Ray, R.D., Gipson, J.M., Egbert, G.D. and Ma, C. (1996). Diurnal/semidiurnal polar motion excited by oceanic tidal angular momentum. Journal of Geophysical Research 101: doi: 10.1029/96JB01649. issn: 0148-0227.

The axial component of the oceanic tidal angular momentum (OTAM) has been demonstrated to be responsible for most of the diurnal and semidiurnal variations in Earth's rotational rate. In this paper we study the equatorial components of OTAM and their corresponding effects on the orientation of Earth's rotational axis, or polar motion. Three ocean tide models derived from TOPEX/Poseidon satellite altimetry are employed to predict the polar motion excited by eight major diurnal/semidiurnal tides (Q1,O1,P1,K1,N2,M2,S2,K2). The predictions are compared with geodetic measurements of polar motion from both long-term observations and during the intensive campaign Cont94. The prograde diurnal and prograde and retrograde semidiurnal periods are treated, whereas the retrograde diurnal polar motion is not treated (because it cannot be observed directly and uniquely.) The comparison shows generally good agreement, with discrepancies typically within 10--30 micro-arc-seconds for the largest tides. The eight tides collectively explain nearly 60% of the total variance in subdaily polar motion during Cont94. This establishes the dominant role of OTAM in exciting the diurnal/semidiurnal polar motion and paves the way for detailed studies of short-period nontidal polar motion. The present accuracy, however, is inadequate to shed light on the prograde diurnal polar libration. ¿ American Geophysical Union 1996

BACKGROUND DATA FILES

Abstract

Keywords
Geodesy and Gravity, Rotational variations, Geodesy and Gravity, Tides—Earth, Oceanography, Physical, Surface waves and tides
Journal
Journal of Geophysical Research
http://www.agu.org/journals/jb/
Publisher
American Geophysical Union
2000 Florida Avenue N.W.
Washington, D.C. 20009-1277
USA
1-202-462-6900
1-202-328-0566
service@agu.org
Click to clear formClick to return to previous pageClick to submit