The ocean is a major component of the global carbon cycle absorbing about a quarter of anthropogenic CO2 emissions every year, modulating the rate of accumulation of carbon in the atmosphere and hence global warming. Increased levels of CO2 in the ocean cause a decline in seawater pH, also known as ocean acidification, with now well-known potential ecological consequences. Sustained, long-term in situ observations are, therefore, crucial to better understand and predict the impact of climate change on ocean ecosystems, increase resilience and develop sound mitigation and adaptation strategies. Furthermore, long-term sustained in situ ocean observations are required to support environmental and climate policies, such as the European Green Deal, and related policies aiming to reach net zero carbon and achieve a sustainable blue economy. To meet this challenge, GEORGE will advance the global technological competitiveness of European ocean observing research infrastructures (EMSO, ICOS, Euro-Argo) through the development and demonstration of a state-of-the-art biogeochemical, multi-platform observing system for characterisation of the ocean carbon system. GEORGE will advance the technology readiness level of novel sensors enabling for the first time systematic autonomous, in situ seawater CO2 system characterisation, and CO2 fluxes on moving and fixed platforms. These sensors will be integrated on state-of-the-art platforms augmented with the latest in autonomous technology enabling new observing capability. Technologies, methods and SOPs for carbon observing will be harmonised across a framework for multi-platform, cross-ERIC ocean observing, from sensor to data repositories. GEORGE will build capacity in ERICs through the provision of training in the use of new technologies and SOPs on data handling and reporting to staff and member organisations. Technology will be co-developed between industry and ERICs ensuring direct route to market and potential for scalability.