The ARGO floats

Balise ARGOArgo is an observation system for the Earth's oceans that provides real-time data for use in climate, weather, oceanographic and fisheries research. Argo consists of a large collection of small, free-drifting profiling floats deployed worldwide.

Map of the Argo float network - January 2010.

The Argo program was designed to operate on the same 10-day duty cycle to match the existing satellite measurements of the ocean's sea surface. With such measurements, information about temperature, mass redistribution, or surface currents can be inferred.

Sources : Argo Portal ( and Wikipedia.

Argo floats drift at a fixed pressure (usually around 1000 metres depth) for 10 days. After this period, within the relatively short time of around two hours, the floats move to a profiling pressure (usually 2000 metres deep) then rise, collecting instantaneous profiles of pressure, temperature, and salinity data on their way to the surface. Once at the surface, the floats remain there for under a day, transmitting the data collected via a satellite link back to a ground station and allowing the satellite to determine their surface drift. The floats then sink again and repeat their mission.
source :

The data are then transmitted to scientists on shore via satellite before the floats plunge to thousands meters of depth. The data collected are freely available to everyone, without restrictions. Argo deployments began in 2000 and by November 2007 and is now 100% completed.

Documents, brochures


Argo Portal
International Argo Information Centre