E-AIMS: Euro-Argo Improvements for the GMES Marine Service
The overall objective of the project was to improve the European contribution to the international Argo observing system and to prepare the next scientific and operational challenges for in-situ monitoring of the world ocean. The main objective was to prepare the evolutions of Argo floats for the next decade: improved reliability and life time, telecommunication capabilities, biogeochemical observations, deeper measurements, under ice operations in the polar seas, sampling of marginal seas. All these evolutions are essential to improve our knowledge on the role of ocean on climate and for operational oceanography.
The Copernicus Marine Environment Monitoring Service (CMEMS)
Impacts and Benefits
The science of climate dynamics and climate change is one of the most pressing issues of our century. Understanding and predicting changes in both the atmosphere and the ocean are needed to guide international actions and to optimize governments' policies. In-situ observations are indispensable to implement a comprehensive Global Observing system by combining space-based systems measuring surface properties with float technology giving access to property changes of the ocean interior. In-situ and satellite data are now routinely assimilated in ocean models to elaborate ocean products. At European level, GMES Marine Service (MyOcean and MyOcean2) provides in real time or in delayed mode (re-analyses) integrated description and short-term forecast of the ocean state to serve a wide range of applications:
- marine environment monitoring
- weather forecasting
- maritime safety and pollution forecasting
- national security
- the oil & gas industry
- fisheries management and coastal and shelf-sea forecasting
- ocean, climate, and ecosystem research
Argo is now the single most important in-situ observing system for operational oceanography and the Copernicus Marine Environment Monitoring Service (CMEMS). The implementation of Argo results from an outstanding international cooperation, with more than 30 countries involved in the development and maintenance of the array. To strengthen, consolidate and integrate their efforts and contributions to the Argo programme, several European countries are collaborating and have agreed to join in the establishment of a new European legal entity: the Euro-Argo ERIC (European Research Infrastructure Consortium). The main challenges for Argo and Euro-Argo are:
- to maintain the global array and ensure its long term sustainability
- to prepare the next phase of Argo with an extension towards biogeochemistry, the polar oceans, the marginal seas and the deep ocean.
Meeting such challenges is essential for the long term sustainability and evolution of the CMEMS. It requires major improvements in Argo float technology, which will be soon available from float manufacturers. They require, however, extensive testing at sea before they can be used for operational monitoring. The Euro-Argo data centers need also to be upgraded so that they can handle these new floats. E-AIMS organised an end-to-end evaluation of new Argo float technology (from float design down to their use). Observing System Evaluations and Sensitivity Experiments have also been conducted to provide robust recommendations for the next phase of Argo that take into account Copernicus Marine Environment Monitoring Service, seasonal/decadal climate forecasting and satellite validation requirements. E-AIMS thus demonstrated the capability of the Euro-Argo infrastructure to conduct R&D driven by CMEMS needs and demonstrated that procurement, deployment and processing of floats for CMEMS can be organised at European level.
Several lines of technological R&D was proposed, involving the sensors and the observed variables, the operating environment, and the data transmission. Those activities conducted in the laboratory and in close interaction with European float manufacturers. Floats were acquired and field tested at sea. The complete data system was improved and evaluated as part of a real-time assessment. The following activities have been done:
- To conduct biogeochemical Argo experiments in the Atlantic and in the Nordic Sea and Black Sea to address climate relevant issues in marine biogeochemistry and the coupling between physics and biology. Additional parameters of high priority include chlorophyll-a (a proxy for phytoplankton biomass), dissolved oxygen (a key parameter to characterize the health of the ocean), nitrate (the primary source of new nitrogen) and particle carbon (relates to the quantity of living and dead matter).
- Evaluate and further improve new float technology for observations deeper (3500-4000 meter) than the nominal 2000 meter presently reached. Deeper measurements are needed to constrain the deep ocean property fields for climate monitoring and long term prediction. Deeper measurements will also improve our ability to assess global sea level changes and climate related signals.
- Develop specifications and algorithms (sea ice detection and positioning) and testing of floats to extent the array into the seasonal ice zones and marginal seas of European interest (Nordic, Mediterranean and Black seas).
- Improve performance of Argo floats while maintaining low communication and hardware costs and perform field tests (Mediterranean and Atlantic Ocean). Performance improvements include new telecommunication systems (Argos-3 and Iridium) and increase bandwidth, addition of new sensors, improved surface layer sampling, enhanced vertical resolution, migrate the grounding problem in marginal seas.
- Conduct R&D on the next generation of Argo profiling floats and demonstrate several major innovations on Argo float technology in a complete real time assessment, from in-situ observations to the availability of the data for operational centers, after reception, processing and validation by the Euro-Argo data centers.
- The Calibration/Validation activities address the evolving requirements brought about by new satellite missions, and the necessity to elaborate high level products which take full account of, and merge, the accuracy and sampling characteristics of the different observing systems. They will also contribute to the definition of the future extended Argo missions.
The work plan was structured along 6 work-packages (WP) and 25 tasks:
- WP1 concerned the management of the project.
- WP2 covered float technology R&D activities and organised the in depth evaluation of new generation Argo floats.
- WP3 and WP4 provided a summary of initial and future requirements for Argo for the Copernicus Marine Environment Monitoring Service, seasonal/decadal climate forecasting (WP3) and satellite Cal/Val activities (WP4). Impact and design studies were then carried out to propose robust and quantitative recommendations for the evolution of Argo.
- WP5 concerned the evolution of Euro-Argo data centres so that they can handle the new Argo floats. WP5 developed and tested delayed mode QC methodologies for oxygen and biogeochemical floats that were used in WP2.
- WP6 covered float data processing in real time and delivered/used by MyOcean (CMEMS) and satellite Cal/Val teams. WP6 also included the synthesis of results (long term roadmap of Euro-Argo to better serve CMEMS).
- WP7 was the scientific and technical project coordination.
- WP8 included communication and dissemination activities of the project.