What are the different uses of Argo data?
Profiling float data have an enormous range of applications. Asthe float array grows and Argo data become more and more abundant there is an increasing body of scientific literaturebased wholly or partly on Argo. The project maintains a bibliography of peer- reviewed papersthat refer to profiling floats. Additionally, many new research papersare in preparation (papers in press) or about to be published. Early applications of Argo data were highlighted in Argo's First Science Workshop held in Tokyo in November 2003. More recent applictions of Argo data were presented at the Second Argo Science Workshop in Venice in March 2006. The Third Argo Science Workshop was held in Hangzhou, China in March 2009.
Argo data use falls into three main categories: educational uses, operational uses and research uses. Read the synopsis of each data type and follow the links to more detailed pages.
Argo data are easy to access and are truly global. Their relevance to climate issues suchas global warming that have great socio-economic relevance makes Argo an ideal vehicle through which to highlight the importance of the oceans to the general public andparticularly to schools. The Educational usepage highlights the three main focuses of Argo education and outreach: curriculum for classroom use, outreach workshops for scientists, and online tools for the general public.
Centers in Australia, France, Italy, Japan, Norway, the UK and the USA routinely produce global and regional analyses of subsurface properties using the Argo data stream. These are available on the world wide web (see the Use by Operational Centers page) and will give early warning of significant temperature and salinity anomalies and changes in ocean circulation.
In the Gulf of Alaska and around Japan, Argo data are being used to aid the monitoring of environmental conditions that affect fish stocks and biological productivity.
Each summer the UK Met Office issues a forecast of conditions for the following winter based on the subsurface temperatures in the Atlantic Ocean. Argo data now allow these forecasts to be made with greater confidence.
At short time scales, Argo data have been used tostudy the evolution of near-surface temperature and salinity beneathtropical cyclones. The data show clear temperature differences leftand right of the cyclone track, but produce conflicting patterns ofsalinity change. Monsoons and ENSO events dominate the low-latitudeseasonal/inter-annual ocean-atmosphere variability. Argo data, whencombined with TAO/Triton tropical buoy array data, extend the mappingof tropical Pacific Ocean structures, and are also used in ENSOforecast systems. Argo profiles have also revealed the Arabian Seaspace-time response during the summer monsoons of 2002 and 2003.
Many results focused on exploration of thecirculation and the definition of the properties and abundance ofwinter-formed mode waters in mid-latitude ocean basins. This couldeven be done in areas such as the Okhotsk Sea, where there isextensive ice cover in some years. Twelve operational analysis/forecast centers routinely use Argo data, and through GODAE,are routinely producing ocean state products. Improvements in oceanpredictions from assimilating Argo data were demonstrated at theworkshop. These give an exciting foretaste of the likely impact ofthe full Argo array when combined with remote sensing data.
With over 3200 floats reporting and more than 10,000 profiles per month being delivered from the Argo array, never before have oceanographers and climate scientists had such a comprehensive subsurface ocean data set. 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.
The global Argo dataset is not yet long enough to observe global change signals. Seasonal and interannual variability dominate the present 6-year globally-averaged time series. Sparse global sampling during 2004-2005 can lead to substantial differences in statistical analyses of ocean temperature and trend (or steric sea level and its trend, e.g. Leuliette and Miller, 2009). Analyses of decadal changes presently focus on comparison of Argo to sparse and sometimes inaccurate historical data. Argo's greatest contributions to observing the global oceans are still in the future, but its global span is clearly transforming the capability to observe climate-related changes.