Webb Research Corporation APEX profilers play a major role in the Argo program, the largest oceanographic experiment ever undertaken. A collaboration between 50 research and operational agencies from 26 countries, Argo comprises a global array of 3,000 free-drifting profiling floats. It provides, for the first time, continuous monitoring of the temperature, salinity, and velocity of the upper 2000 m of the world ocean, with all data relayed and made publicly available within hours after collection.

Over 2000 APEX floats have been delivered for Argo deployment since the program began in 2000. WRC engineers have worked closely with scientists and program managers in the United States, Canada, and many other nationsto insure the success of the Argo program and of individual floats.

The Argo program was designed to operate on the same 10-day cycle as the Topex/Poseidon and Jason-1 satellites, which measure changes in the surface topography of the ocean. Information about temperature, mass redistribution, or surface currents can be inferred from these satellite measurements. The complimentary nature of the two programs inspired the Argo program’s name: Argo was the mythical Greek ship used by Jason and the Argonauts on their quest for the Golden Fleece.

Argo floats drift at a fixed pressure (usually around 1000 meters depth) for 10 days. Then, within the relatively short time of around six hours, the floats move to a profiling pressure (usually 2000 meters deep) before rising and collecting profiles of pressure, temperature, and salinity on their way to the surface, where they transmit the data collected via a satellite link back to a ground station. The floats then sink again and repeat their missions. Argo float lifetime is about four years.

Argo is unique among research programs in freely offering real-time data to anyone, with no constraint on use, via the World Wide Web from two global data servers located in the USA and France.