IMPROVING OCEAN TIDE PREDICTIONS BY USING ADDITIONAL SEMIDIURNAL CONSTITUENTS FROM SPLINE INTERPOLATION IN THE FREQUENCY-DOMAIN

The improvement in accuracy that can be obtained by increasing the number of constituents in the model at present used for tidal height corrections in the GDRs of satellite altimetric measurements is analysed by referring to the performance of the Harmonic Method in predicting tides at a selected number of locations in the world where observations of sea level variations are available. Given the interest in such improvements, a way of extending the existing data set is proposed, without the need to run a new model of the world's oceans: the method relies on the concept of admittance. World's oceans maps are derived for five additional constituents, and the differences in predicted heights resulting from these improvements are evaluated.