Popis: |
We compute the deflections of the vertical line over sea from the altimeter data using simple difference, which reduces effectively the influence of the Dynamic Ocean Topography (DOT) and systematic residuals on the deflections of the vertical line. Then, we present a covariance function to approach precisely the marine geoid from the deflections of the vertical line in view of the homogeneity and isotropy of the covariance functions of the anomalous potenial elements. And the determination of the geoid makes it possible to separate precisely the DOT from the sea surface height (SSH). Finally, the global marine geoid and DOT are predicted from the Topex/Poseidon, ERS-1/2 and Geosat altimeter data, which prove that the above-mentioned methods are scientific and reasonable. |