COMFORT will close knowledge gaps for key ocean tipping elements under anthropogenic physical and chemical climate forcing through an interdisciplinary research approach. It will provide added value to decision and policy makers in terms of science based safe marine operating spaces, refined climate mitigation targets, and feasible long-term mitigation pathways. We will determine the consequences of passing tipping points in physical tipping elements for the marine carbon, oxygen, and nutrient cycles, as well as tipping points in biogeochemical tipping elements. The respective impact on marine ecosystems will be determined. Projections of the Earth system and impact studies have so far been carried out sequentially in a chain from scenarios to projections to off-line impact studies. This sequential workflow has hampered a quick response of the impact community back to revised scenarios and projections for tackling climate mitigation. COMFORT breaks new ground by bringing together experts from Earth system science, oceanography, fisheries science and ecology in a single integrated project who will work in parallel with a consistent set of analysis tools, scenarios, and interoperable models. The strength of COMFORT lies in the system-focused interdisciplinary approach as opposed to existing studies at the level of individual subsystems. The approach will be pursued with a firm link to stakeholders. COMFORT results will contribute to all four expected impacts for this call.