The research unit „Chemical Oceanography“ of the research division „Marine Biogeochemistry“ at GEOMAR invites applications for a Ph.D. position on the development of a chemical sensor for the measurement of dissolved inorganic carbon (DIC) in seawater.The candidate will work in thelarge consortium ’AIMS3’that forms part of the German DAM (Deutsche Allianz Meeresforschung) Mission on ‘Marine CarbonSinksinDecarbonizationPathways’. The DAM Mission will explore ocean carbon sink options and develop environmental monitoring approaches as part of thedecarbonization strategy. AIMS3 will develop improved environmental monitoring technologies for off-shore carbon capture and storage(CCS)sites, and will explore the possibility of CO2storage in deep ocean basalts. The candidate willdesign, develop and demonstrate a DIC sensor for monitoring CCS sites for potential CO2leaks. The PhD project will be conducted in close collaboration with a local marine technology company.The project will involve optimisation of sensor chemistry and detection technology, sensor miniaturisation and integration into existing physical sensor systems produced by the company. Laboratory and field testing and demonstrations form part of the project. The candidate will work closely with Prof. Dr. Eric Achterbergand Dr Mario Esposito, the local company, and other partners in AIMS3. The candidate will become part of the German DAM Mission ‘Marine Carbon Sinks in Decarbonization Pathways’, and in particular in the AIMS3 project. Regular fieldwork opportunities, including research cruises, will form part of the PhD project for testing and demonstration purposes. We expect the candidate to enrol in the marine science post-graduate school in Kiel, ISOS.