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Determination of ocean tides from the first year of TOPEX/POSEIDON altimeter measurementsAn improved geocentric global ocean tide model has been determined using 1 year of TOPEX/POSEIDON altimeter measurements to provide corrections to the Cartwright and Ray (1991) model (CR91). The corrections were determined on a 3 deg x 3 deg grid using both the harmonic analysis method and the response method. The two approaches produce similar solutions. The effect on the tide solution of simultaneously adjusting radial orbit correction parameters using altimeter measurements was examined. Four semidiurnal (N(sub 2), M(sub 2), S(sub 2) and K(sub 2)), four diurnal (Q(sdub 1), O(sub 1), P(sub 1), and K(sub 1)), and three long-period (S(sub sa), M(sub m), and M(sub f)) constituents, along with the variations at the annual frequency, were included in the harmomnic analysis solution. The observed annual variations represents the first global measurement describing accurate seasonal changes of the ocean during an El Nino year. The corrections to the M(sub 2) constituent have an root mean square (RMS) of 3.6 cm and display a clear banding pattern with regional highs and lows reaching 8 cm. The improved tide model reduces the weighted altimeter crossover residual from 9.8 cm RMS, when the CR91 tide model is used, to 8.2 cm on RMS. Comparison of the improved model to pelagic tidal constants determined from 80 tide gauges gives RMS differences of 2.7 cm for M(sub 2) and 1.7 cm for K(sub 1). Comparable values when the CR91 model is used are 3.9 cm and 2.0 cm, respectively. Examination of TOPEX/POSEIDON sea level anomaly variations using the new tide model further confirms that the tide model has been improved.
Document ID
19950049124
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Ma, X. C. (Univ. of Texas, Austin, TX United States)
Shum, C. K. (Univ. of Texas, Austin, TX United States)
Eanes, R. J. (Univ. of Texas, Austin, TX United States)
Tapley, B. D. (Univ. of Texas, Austin, TX United States)
Date Acquired
August 16, 2013
Publication Date
December 15, 1994
Publication Information
Publication: Journal of Geophysical Research
Volume: 99
Issue: C12
ISSN: 0148-0227
Subject Category
OCEANOGRAPHY
Funding Number(s)
CONTRACT_GRANT: JPL-958122
Distribution Limits
Public
Copyright
Other