COMFORT. Our common future ocean in the Earth system -  quantifying coupled cycles of carbon, oxygen, and nutrients for determining and achieving safe operating spaces with respect to tipping points

COMFORT will identify tipping point in future marine ecosystems induced by climate change and the associated multiple stressors. The impact of these tipping points on ecosystems will then be assessed and the safe operating space to avoid them identified.

Human-induced forcing has instigated an unprecedentedly rapid and pervasive change of the Earth system and climate. Particularly dangerous are changes that, once a critical threshold or tipping point is reached, accelerate strongly and occur much faster than the rate of forcing. COMFORT zooms in on ocean-related tipping points and provides the framework for taking optimal action to limit damage.

Ocean physical and biogeochemical climate is changing due to the uptake of heat and carbon dioxide caused by human activity. Consequences for the ocean are warming, enhanced stratification, changes in circulation, acidification, and loss of oxygen with the potential spreading of dead zones. Ocean extreme events associated with warming, deoxygenation and acidification are expected to become more frequent and intense. The Fifth Assessment Report of the Intergovernmental Panel on Climate Change specifically highlighted expected negative impacts of climate change on marine organisms and ecosystem services (including marine food production) due to warming, deoxygenation, and ocean acidification. The overall challenge is therefore to quantify and project the likelihood of physical, chemical and biological tipping points in ocean and their interactions and to accurately assess the implications of climate-induced marine tipping points for the Earth system as a whole. This challenge includes achieving refined quantification of mitigation targets, safe operating spaces, and feasible pathways for transformation towards sustainability.

The overall objective of COMFORT is to close knowledge gaps for key ocean tipping elements within the Earth system under anthropogenic physical and chemical climate forcing through a coherent interdisciplinary research approach, and to 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. It focuses on the triple threat of warming, deoxygenation, and ocean acidification, and how to optimally deal with this threat.