Skip to content

Asia-Pacific Network for Global Change Research

Asia-Pacific Network for Global Change Research

Read our Science Bulletin
Peer-reviewed publication

SEASAT and GEOSAT revisited: using sea level measurements to improve satellite altimeter orbits

Global maps of sea surface height can be reconstructed by fitting patterns of satellite altimeter-derived sea level variability to historical tide gauge measurements. The accuracy of these maps is uncertain because of the limited sampling available in the historical record. Reconstructed maps from August 9, 1978 and August 9, 1987 are composed with maps derived from 17-day repeat orbit sampling provided by Seasat and GEOSAT altimetry, respectively, to evaluate the fidelity of the sea level reconstructions. Given sufficiently accurate reconstructed time series, it is shown that it is possible to improve orbit error filtering procedures to better account for oceanographic signals. This could improve the accuracy of the Seasat and GEOSAT orbits and the utility of the altimeter measurements for ocean and ice studies relying on these unique historical altimetric records.