An observation network was initiated in 2021 in the framework of the CocoriCO2 project to monitore carbonate parameters along the French coastal systems. Six sites were selected along the French Atlantic and Mediterranean coastlines based on their importance in terms of shellfish production and the presence of high- and low-frequency monitoring activities. At each site, autonomous pH sensors were deployed both inside and outside shellfish production areas, next to high-frequency CTD (conductivity-temperature-depth) probes operated through two operating monitoring networks (SNO COAST-HF and Ifremer ECOSCOPA). pH sensors were set to an acquisition rate of 15 min and discrete seawater samples were collected biweekly in order to control the quality of pH data (laboratory spectrophotometric measurements) as well as to measure total alkalinity and dissolved inorganic carbon concentrations for full characterization of the carbonate system. While this network has been up and running for more than two years, the acquired dataset has already revealed important differences in terms of pH variations between monitored sites related to the influence of diverse processes (freshwater inputs, tides, temperature, biological processes).    

The aim of this project is to implement a sampling network in order to study climate variability in ocean water around the Iberian peninsula and the Bay of Biscay, to determine the flows of heat, freshwater, nutrients and C02 in wastewater, and relationship with NAO. This contributed to international climate change programmes and to the beginning of systematic study of the region. Furthermore, it facilitates the use of a digital model in the region. The main aim of the VACLAN project is to improve observation capacity and the use of the new tools available used to characterize climate change: remote sensing for the study of surface waters, drifting buoys for upper and mid waters, and moored instruments and hydrographic stations for studying the water column. The use of these tools along with digital modelling will make it possible to characterize CO2 flow and the physio-chemical flow in such a large area, where the border current is the Atlantic. Furthermore, once checked and validated, the data in this system will be made available for academic scientific communities and included in digital forecasting models.