Gulf Stream dynamic topography measured from space



On March 9, 1989, the Navy-sponsored GEOSAT radar altimeter satellite completed 50 cycles over its 17-day exact repeat ground track. Results obtained from analyzing the mission data set were presented at the Eleventh GEOSAT Users Meeting held March 23 at the Johns Hopkins University Applied Physics Laboratory (APL). Publication of the results is planned for a special 1989 issue of the Journal of Geophysical Research, which will focus on GEOSAT.

Development of a synthetic geoid processing technique that allows the total dynamic topography of the Gulf Stream front and eddy system to be measured was reported by scientists from the Naval Ocean Research and Development Activity (NORDA), Woods Hole Oceanographic Institution (WHOI), Harvard University and APL. The “synthetic geoid” is realized by subtracting the climatology of the surface topography along a ground track (the mean circulation topography) from the mean of the altimeter data along the track. The technique dramatically increases the scientific value of radar altimeter data by removing the distortion and signal reduction caused by subtracting a mean sea surface that includes the mean circulation.