Portal de Periódicos da CAPES

Verification of Geosat sea surface topography in the Gulf Stream extension with surface drifting buoys and hydrographic measurements

1990; American Geophysical Union; Volume: 95; Issue: C3 Linguagem: Inglês

10.1029/jc095ic03p03007

2156-2202

Jürgen Willebrand, Rolf H. Käse, Detlef Stammer, Hans‐Harald Hinrichsen, W. Krauss,

Marine and coastal ecosystems

Altimeter data from Geosat have been analyzed in the Gulf Stream extension area. Horizontal maps of the sea surface height anomaly relative to an annual mean for various 17‐day intervals were constructed using an objective mapping procedure. The mean sea level was approximated by the dynamic topography from climatological hydrographic data. Geostrophic surface velocities derived from the composite maps (mean plus anomaly) are significantly correlated with surface drifter velocities observed during an oceanographie experiment in the spring of 1987. The drifter velocities contain much energy on scales less than 100 km which are not resolved in the altimetric maps. It is shown that the composite sea surface height also agrees well with ground verification from hydrographic data along sections in a triangle between the Azores, Newfoundland, and Bermuda, except in regions of high mean gradients.