There is an increasing concern about global change and its regional impact. For example, sea level is rising at an accelerating rate of 3 mm/year, Artic sea ice cover is shrinking and high latitude areas are warming rapidly. These effects are caused by a mix of long-term climate change and natural variability. Lack of sustained observations of the atmosphere, oceans and land has hindered the development and validation of climate models. For example, a recent analysis concluded that the currents transporting heat northwards in the Atlantic and influencing western European climate had weakened by 30% in the past decade. This result had to be based on just five research measurement campaigns spread over 40 years. Was this change part of a trend that might lead to a major change in the Atlantic circulation, or due to natural variability that will reverse in the future, or is it an artefact of the limited observations?


Concerns about the lack of observations of key factors that influence earth’s climate led governments to form the Global Earth Observation System of Systems (GEOSS) in 2003. In Europe there is an initiative on Global Monitoring for Environment and Security (GMES). GEOSS and GMES aim to provide the measurements needed to make predictions of how global change will influence weather, climate, energy, water, health and disasters. The climate and ocean components of GEOSS are delivered by the Global Climate Observing System (GCOS) and the Global Ocean Observing System (GOOS).


The international ARGO program (for more details, see was initiated in 1999 as a pilot project endorsed by the Climate Research Programme of the World Meteorological Organisation, GOOS, and the Intergovernmental Oceanographic Commission. The Argo network is a global array of autonomous instruments, deployed over the world ocean, reporting subsurface ocean properties to a wide range of users via satellite transmission links to data centres.For more informations on floats, go to the page Activities/Floats.

In 2007, Argo reached its initial target of 3000 profiling floats.


Argo is the first-ever global, in-situ ocean observing network in the history of oceanography, providing an essential complement to satellite systems. It is now the major, and only systematic, source of information and data over the ocean’s interior. It is an indispensable component of the Global Ocean Observing System required to understand and monitor the role of the ocean in the Earth’s climate system.

That's why maintaining the array's size and global coverage in the coming decades is the next challenge for Argo, and Euro-Argo will contribute for the European component to this global network.