Back in 2001, we first reported on the Argo project and its plan to deploy a network of 3,000 robots throughout the oceans of the world to capture precise measurements of temperature (+/- 0.005° C) and salinity. The number of deployed robot floats reached 3,000 in 2007. The robots continuously take measurements as they move from the surface to a depth of 2000 meters and back. They've been returning 100,000 measurements per year and, according to a recent news release, in January they passed the 1,000,000 measurement milestone. From the website:
Over 100 research papers per year are now being published using Argo data covering a broad range of topics including water mass properties and formation, air-sea interaction, ocean circulation, mesoscale eddies, ocean dynamics, seasonal-to-decadal variability, and global change analysis. A key objective of Argo is to observe ocean signals related to climate change. This includes regional and global changes in ocean temperature and heat content, salinity and freshwater content, the steric height of the sea surface in relation to total sea level and large-scale ocean circulation.
When the project started over a decade ago there was still widespread uncertainty over the rate and nature of climate change. Today, thanks in part to the precise data returned by these robots, researchers are able to build and test much more accurate models of climate change and carbon sequestration. As rising ocean temperatures cause more and more dramatic weather events, data from the Argo robots will be increasingly important to researchers as they try to accurately model and predict the coming changes. The Argo network data itself is available if you'd like to download it or get it on CD. Argo data is also available through standard climate research databases like the KNMI Climate Explorer and is now the primary source of data used for the NOAA Global Ocean Heat and Salt Content graphs. For more see the special Argo Brochure (PDF format) released for the one millionth measurement profile. Read on to see some cool videos of the Argo bots in action.
CC BY-NC-ND Argo photo by flickr user fruchtzwerg's world