How We Observe the Ocean
Argo Profiling Floats
Argo is a global array of 3,000 free-drifting, profiling floats that measure the temperature and salinity of the upper 2000 m of the ocean. The array provides continuous monitoring of the temperature, salinity, and velocity of the upper ocean. Over twenty countries and the European Union contribute to the international Argo program. The U.S. component is implemented by NOAA.
- Argo Array
- Argo Links
Deployment of the Argo array began in 2000, and reached 100% of its initial design goal in 2007. Because the typical lifetime of an Argo float is 4-5 years, maintaining the array at a level of 3,000 floats requires replacement of about 800 floats per year. It is now recognized, however, that additional floats are needed, because high latitude areas of the ocean require a higher density of floats to adequately characterize the state of the ocean.
The array of 3000 floats provides 100,000 temperature/ salinity (T/S) profiles and velocity measurements per year distributed over the global oceans at an average 3-degree spacing. Floats cycle to 2000m depth devery 10 days. The measurements from the Argo array have demonstrated the need for climate observations below 2000 meters in depth in order to measure the total global heat storage in the ocean; designing and building deep diving floats is a critical technology challenge, as is expanding measurements to better sample the marginal seas and rapidly flowing boundary currents.
Argo data are publically available in near real-time via the Global Data Assembly Centers (GDACs) in Brest, France and Monterey, California after an automated quality control (QC), and in scientifically quality controlled form, delayed mode data, via the GDACs within six months of collection.
Argo Home Page
Argo Global Data Assembly Centers