The main mission of PIRATA is to measure surface fluxes of momentum and heat, together with corresponding changes in the upper-ocean thermal structure, through continuous and freely accessible observations of atmospheric and ocean variables to support real-time monitoring and forecasting. Consequently, fixed observational networks using tropical moorings were deployed, with architectures specifically adapted to the Atlantic. Today, 17 meteo-oceanographic buoys are deployed across the tropical Atlantic with two main objectives:

• Operational support: Provide meteorological and oceanographic measurements transmitted daily via satellite to data centers for use in operational oceanographic, weather, and climate forecasts, helping to correct biases in numerical model predictions.
• Scientific research: Support process studies aimed at understanding and improving oceanic and atmospheric numerical models, for example through better numerical parameterizations.

In situ observations thus remain a critical source of information for enhancing the quality of model and satellite products, particularly for identifying spurious trends.