As an interactive and user driven initiative, OCEAN2 will establish and advance a European digital ocean framework on which all marine data, modelling and simulation along with HPC capacities, AI algorithms and specialized tools will form a new European shared capacity to access, manipulate, analyse and visualise marine information. It will enable users and partners to create ocean related development scenarios addressing issues such as green energy developments (renewable, non-renewable), mining impacts, fisheries and mariculture, marine protected area siteing, nature based solutions and ocean based tourism. Digital twin applications will allow to quantify benefits and environmental change and provide powerful visualizations based on data and model derived knowledge for experts, stakeholders as well as interested citizens. OCEAN2 will empower ocean professionals including scientific and expert users to create their own local or topical digital twin applications addressing ‘their ocean specific issue or challenge’ by using standard workflows, data and tools. These could generate new information or new models that could be reintegrated in the DTO digital framework to enrich the offer and increase its accuracy or completeness in a collaborative manner. Decision makers will gain a precise tool to take evidence-based decisions, and SMEs and Blue economy partners will gain a solution around which to build their services based on the DTO infrastructure. In a virtuous loop, ocean researchers, engineers and digital service providers will benefit from this platform to enrich the data lake and tools to further develop their investigation capacity, develop trans-disciplinary cooperation and bridge the gap between science and society.