This investigation describes preliminary results of the SEASAT radar altimeter significant wave height measurements. A comparison of the results obtained by the SEASAT on-board algorithms with results obtained by a full wave-form analysis of the SEASAT data using the Fedor method, indicates that for wave heights up to 4 meters the "on-board" algorithm over estimates the

by a value of 10 cm with a standard deviation of 50 cm. These altimeter measured results are compared with results obtained from the FNWC charts, several surface buoys and one GEOS-3 crossing. The comparison indicates that the satellite

measurements agree with the surface truth measurements to within

cm for a range of wave-heights up to 4 meters.