Ocean surface measurement using elevations from GEOS-3 altimeter

Remote sensing of the ocean surface topography from the GEOS-3 satellite has confirmed that the altimeter can detect the topographic changes relative to an equipotential surface and due to the dynamic processes, thus providing a direct measurement of the geostrophic component of the ocean surface current. Maps of the ocean surface topography calculated over a one-month period, with a 20-cm contour interval, are prepared for the last half of 1975. The Gulf Stream is observed by the rapid slope change shown by the crowding of contours. Cold eddies associated with the current are seen as roughly circular isolated depressions in the open ocean areas.