Argo Deployments

Oceanographic Operations (Candice Hall & Liz Zele)


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.  It uses a fleet of robotic floats that spend most of their life at depth and that surface regularly to make temperature and salinity profile measurements. This will allow, for the first time, continuous monitoring of the temperature, salinity, and velocity of the upper ocean, with all data being relayed and made publicly available within hours of collection. 

The ARGO floats are self-contained units that control their own buoyancy. After deployment, they sink to a depth of 1000m. There they remain for the next 10 days, before dropping down to 2000m. Upon reaching that depth they return to the surface, taking measurements along the way.  These data are then transmitted via satellite to their home base before the ARGO buoy submerges, to start the process again. Most incredible is their battery and operational life of over six years!

As over 90% of the observed increase in heat content of the air/land/sea climate system over the past 50 years occurred in the ocean [Levitus et al., 2001], Argo will effectively monitor the pulse of the global heat balance. It will improve our understanding of the ocean's role in climate, as well as spawning an enormous range of valuable ocean applications. Argo is a major contributor to the WCRP's Climate Variability and Predictability Experiment (CLIVAR) project and to the Global Ocean Data Assimilation Experiment (GODAE).  The Argo array is part of the Global Climate Observing System/Global Ocean Observing System (GCOS/ GOOS).’ (ARGO, 2005)

The floats are contributed by many countries but all data are freely available via the ARGO website or through participating institutes. Deployments began in 2000 and by January 2005, the tally of floats deployed worldwide was 1584, as shown in figure 1 below (ARGO, 2005) During August 2005, the target of 2000 float deployments had been reached.


Figure 1:  Argo Deployments as of January 2005


Thank you to all of those who helped with the launches and to all those spectators who provided moral support!

Those interested in following the progress of our floats should log on to the PMEL website (it’s easier than the ARGO website) Clicking through to "data" gives you a map of the Pacific showing where all the PMEL floats last reported.

"Present Status" will then give a list of all the floats; each float number is a link to its data (and you can choose profile, section, trajectory, or engineering). The floats have about 6 different numbers that can identify them depending who's asking. Alternate numbering schemes are still a bit of a problem even on the PMEL web site: the float has a controller that has a different serial number than the one printed on the hull; it reports the controller number, so you'll need to know the translation to look up floats deployed by NOAA Ship David Starr Jordan.

 Hull number 2326 has board number 2570

 Hull number 2327 has board number 2571

 Hull number 2328 has board number 2572

 Hull number 2329 has board number 2573

The chart to the right indicates where the ARGO floats were deployed.





 ARGO. ARGO Home Page. The previous link is a link to Non-Federal government web site. Click to review NOAA Fisheries disclaimer . January 2005.

Levitus, S., J. I. Antonov, J. Wang, T. L. Delworth, K. W. Dixon, and A. J. Broccoli. 2001. Anthropogenic warming of Earth's climate system. Science 292(5515): 267-270.


Last modified: 12/24/2014