Globally as well as in Germany, type and scale of CDR are a key consideration in developing pathways to greenhouse gas neutrality. CDR measures include terrestrial, geological, material-based and marine approaches. The state of knowledge varies widely across methods. Not only technical limits to CO₂ uptake need to be explored, but realistic potentials need to be estimated that avoid conflicts over resources such as water or land, take societal processes into account, are ecologically sustainable, and are economically and politically feasible. It is essential to understand how the different CDR measures are to be evaluated across all these dimensions and compare against each other and also interact with each other in order to define their role in climate change mitigation pathways. But so far, no common framework exists to compare CDR measures and additionally evaluate trade-offs of CDR with other sustainability goals.
The synthesis project, CDRSynTra, that accompanies the CDR program unites the research results of the projects. Its overarching goal is to evaluate the potentials and impacts of the various methods in a comprehensive, common assessment framework. This will lay the scientific foundations on which a socially acceptable and ecologically and economically sensible mix of CDR methods can be developed. To this end, CDRSynTra works in three research pillars on Earth system analysis, emission reduction and CO₂ removal pathways, and governance and policy design. A comprehensive screening of the international CDR research landscape optimizes the research impact.
To ensure that proposed emission reduction and CO₂ removal pathways are feasible, an intensive dialogue with stakeholders is maintained throughout the program. Even the selection of relevant criteria for an assessment framework can only be made in close exchange with the public, industry and politics. Transparent communication of the research results to the public is also a major concern of the project and is implemented, for example, through museum exhibitions and a school program. Wherever possible, not only linear formats of science communication, but participatory and dialogue-oriented approaches are pursued.
CDRSynTra also acts as the interface to the research mission “Marine carbon sinks in decarbonisation pathways” of the German Marine Research Alliance and will be responsible for the overall scientific synthesis on land-based and marine CDR methods, which can thus be considered in comparison to each other and in combination.