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Ocean topography/currents

Ocean surface topography data contain information that has significant practical applications in such fields as the study of worldwide weather and climate patterns, the monitoring of shoreline evolution and the protection of ocean fisheries. Ocean circulation is of critical importance to the Earth’s climate system. Ocean currents transport a significant amount of energy from the tropics towards the poles, leading to a moderation of the climate at high latitudes. Circulation can be deduced from ocean surface topography, which may be readily measured using satellite altimetry.
Detailed MeasurementDescription*InstrumentsTimeline
BathymetryThe measurement of water depth. [Unit of measurement - m]7 instruments
Coastal sea level (tide)
Deviation of sea level from local references in coastal zones, caused by local currents and tides (astronomical and wind-induced) - Measuring units cm, Uncertainty units cm0 instruments
Ocean dynamic topography
Deviation of sea level from the geoid caused by ocean currents (that is after corrections for tides and atmospheric pressure effects) - Physical unit: [ cm ] - Accuracy unit: [ cm ].12 instruments
Ocean surface currents (vector)
Water flow on ocean surface - Physical unit: [ cm/s ] - Accuracy unit: [ cm/s ] intended as vector error, i.e. the module of the vector difference between the observed vector and the true vector - Measuring Units cm/s, Uncertainty Units cm/s6 instruments
Ocean velocity
Ocean motion measured at various depth levels - Measuring and Uncertainty Units cm/s1 instrument
Sea level
Actual, local sea level inclusive of mean sea level and perturbations (tides, etc.) [Unit of measurement - cm]15 instruments
* Description adapted from WMO.