TOPEX/Poseidon was the first space mission that allowed scientists to map ocean topography with sufficient accuracy to study the large-scale current systems of the world's ocean. Although this image was constructed from only 10 days of TOPEX/Poseidon data (October 3 to October 12, 1992), it reveals most of the current systems that have been identified by shipboard observations collected over the last 100 years.
Ocean surface topography or sea surface topography, also called ocean dynamic topography, are highs and lows on the ocean surface, similar to the hills and valleys of Earth's land surface depicted on a topographic map.
These variations are expressed in terms of average sea surface height (SSH) relative to Earth's geoid.[1] The main purpose of measuring ocean surface topography is to understand the large-scale ocean circulation.
^[In most absolute form, it may be expressed in terms of a geocentric radius.]