Ocean react roughly as a huge inverted barometer, coming up when atmospheric pressure is low (air weighting less over the surface), and down when pressure rise. To take these effects into account (they can reach 20 cm over the ocean level), the ocean response has to be modelized.

On October 14, 2005, the first Mercator global 1/4° ocean forecasting bulletin was published

Cryosat will be launch on October 8, 2005 to measure sea ice topography

Sea surface salinity measurements are not yet done by satellite, and thus not global. Using models assimilating altimetry is a way to circumvent this.

The Kon Tiki crossed the Pacific in 1974 from South America to Polynesia. Its path is now seen under the light of altimetry-derived currents.

Forecast quality, in resolution as well as in accuracy, is improved by assimilating data from several altimetry satellites at the same time.

Ocean altimeters are designed for sea surface height measurements. However the possibilities arise of looking at other things; for example, atmospheric liquid water content

eddies tend to go toward the equator when they are anticyclonics (warm eddies), and toward the pole when they are cyclonic (cold eddies)

Sea state forecast are using altimetry. During hurricanes, they are a test for the models -- and an important information for seafarers.

Argo floats provide high quality data complementary to satellite altimetric height. Comparisons are then possible.

The region of Confluence of the Brazil and Malvinas Currents is a very energetic complex region. Satellites provide valuable information in this area which has few in situ time series observations.

Much of the heat transported poleward by the oceans is carried in the "western boundary currents". Year-to-year variations are observed in their extend, that can be correlated with changes in upper ocean heat content.