TEMPORAL VARIABILITY OF GLOBAL TOPEX POSEIDON ALTIMETRY - TIDE AND ANNUAL SIGNALS/

The global power of the differences of altimetric sea heights at collo cated points in the first 44 cycles of the Topex/Poseidon (T/P) missio n, apparently shows the influence of errors in the major tides and lon g period ocean signals. Results show the principal semidiurnal tides ( M2/S2 lumped together) in the Cartwright and Ray (1991) model are prob ably in error globally by 3-4 cm (rms). The dominant fluctuation in th e differences over the 44 cycles (14 months total) arises from an annu al signal of 4-6 cm (rms), significantly greater than long term climat e data suggests (but with considerable uncertainty due to unresolved s emiannual effects).