NOAA Magazine NOAA Home Page

SMALL FLOATS TAKE OCEAN'S TEMPERATURE

March 22, 2002 — The global ocean will eventually have 3,000 fussy nurses taking its temperature every 10 days. Part of the alarm system to warn of an impending El Niño, the Argo fleet of five-foot-tall yellow cylinders ride the waves of the world's oceans, monitoring temperature and salinity during their journey.

"These floats are the weather balloons of the ocean," said Stan Wilson, NOAA Director of International Programs, during a three-day international science meeting, which took place last week in Hobart, Tasmania. "Just like weather balloons travel through the atmosphere gathering data, so do the Argo floats, but they take measurements through the water column."

As the floats drift with the ocean currents, they spend about six hours at the surface before sinking down to 2000 meters (or about 6,000 feet) where they drift for about 10 days. After 10 days, they begin to rise to the surface, recording temperature and salinity data. Once they reach the surface, the floats beam back the data to a satellite that relays it to a ground station.

"Argo has changed the way oceanography is being done," Wilson said. "Before, data were collected and not shared until publication, which could take a great deal of time. Argo data are fully and openly available with no periods of exclusive use by anyone."

The data are often available within hours of being collected.

"The benefit is that the data can be used for operational forecasts as well as by the scientific community thus contributing to our understanding of the role of oceans in climate," Wilson added.

Wilson explained the Argo project to President George W. Bush when he visited NOAA in Silver Spring in February.

There are about 340 Argo floats in the waters today. Plans call for a total of 3,000 by 2006.

Data collected by the floats are used to:

• Develop predictions for the onset of El Niño and thus for major changes in rainfall and other climatic conditions;
• Monitor and understand climate change and measure sea level rise;
• Provide better and more timely information for marine safety and rescue
  Fisheries; and
• Environmental management and protection.

The international Argo effort—which now includes more than a dozen countries—began in 1999. The Argo array is part of the Global Climate Observing System/Global Ocean Observing System (GCOS/GOOS) and contributes to both the Climate Variability and Predicability Experiment (CLIVAR) and the Global Ocean Data Assimilation Experiment (GODAE).

Relevant Web Sites
The Contribution of NOAA Buoys to a Global Ocean Observing System: Benefits to Climate Prediction and Research

Building a Sustained Ocean Observing System for Climate

Office of Global Programs—Climate Observation

Argo

U.S. ARGO Data Center

Argo B-Roll of Deployment from a Ship (video)

Animation with a Narration of the Argo Deployment (video)

Tropical Atmosphere Ocean project

Operational El Niño / Southern Oscillation (ENSO) Observing System

NOAA's CURRENT SEA SURFACE TEMPERATURE MAPS

Media Contact:
Jana Goldman, NOAA Research, (301) 713-2483

 

-end-