The COSYNA observatory measures key physical, sedimentary, geochemical and biological parameters at high temporal resolution in the water column and at the sediment and atmospheric boundaries. COSYNA delivers spatial representation through a set of fixed and moving platforms, like tidal flats poles, FerryBoxes, gliders, ship surveys, towed devices, remote sensing, etc.. New technologies like underwater nodes, benthic landers and automated sensors for water biogeochemical parameters are further developed and tested. A great variety of parameters is measured and processed, stored, analyzed, assimilated into models and visualized.