Integrierter Bewertungsrahmen

Aim of the CDRterra assessment framework

The CDRterra integrated assessment framework aims to structure and enhance transparency in the evaluation of Carbon Dioxide Removal (CDR) methods in Germany., Its key aim is to aiding in societal debates and policy decisions regarding funding and regulation. It supports the integrative evaluation of land- and ocean-based CDR methods, for the future years 2030, 2045, 2050, and 2060. The framework examines numerous indicators in six descriptive dimensions and evaluates them according to certain criteria. It also explores potential synergies and trade-offs among dimensions and other CDR methods. This comprehensive approach aims to provide a consistent basis for evaluating CDR strategies over time. Close collaboration with CDRmare exists to assess both terrestrial and marine CDR options.

Assessment matrix
Scheme about the descriptive information that is used within the CDRterra assessment framework separated into interdisciplinary broad topics (Dimensions) with no or the least overlap possible. A Dimension consists of several criteria forming thematic units within the broad topics of the dimensions

Development of the CDRterra assessment framework

The CDRterra integrated assessment framework builds on the state-of-the art developments of assessments frameworks of climate mitigation options, such as the structuring scheme deployed in the IPCC Special and Assessment Reports (see e.g., AR6-WG3 Ch. 12; AR6-WG3 Annex III Table 8), which have subsequently been adapted specifically to CDR methods (e.g. Förster et al., 2022, Borchers et al., 2024). CDRterra builds on this previous work and expands it in particular in view of:

  • Adjusting and expanding the descriptive information through the expertise across the disciplines represented in CDRterra and through dialogue with various stakeholders groups.
  • More narrowly focussed evaluation of the feasibility of CDR methods (e.g., about constraints and enablers) while others more explicitly with regard to societal values and broader political goals (as expressed, e.g., in the Sustainable Development Goals, human rights or notions of efficiency and risk);
  • Taking future spatio-temporal context with given future climate conditions into account (by conducting assessments situated in 2030, 2045, 2050, 2060, … with future information coming from novel future narratives and different modeling approaches);
  • Assessing CDR portfolio(s) and specific volumes of carbon removal amounts for each CDR method;
  • Addressing potential indirect environmental impacts across regional and global scales in particular when upscaling measures (esp. large-scale biogeophysical effects that alter the mitigation effect by CO2 removal (e.g., changes in ocean heat uptake and land surface properties such as albedo, leaf area and roughness) and biogeochemical feedbacks (ocean carbon uptake and net land carbon flux) that alter the mitigation effectiveness).

Structure of the CDRterra assessment framework

The descriptive scheme provides the basic information that is needed for an integrated assessment of CDR methods. It is sorted along six dimensions: environmental effects, technological readiness, economic efficiency, mitigation effectiveness, political feasibility, and societal implications, particularly public perception (see Figure 1). Further, we defined 70 indicators which provide information by describing certain states or characteristics and are situated on a lower aggregation level than a criterion. In addition, an indicator is separated into one or more variables (not shown).

The evaluative scheme uses the descriptive information to transparently assess the feasibility as well as overarching societal values and broader political goals. The latter are rather normative properties and are called desirability in recently submitted scientific papers by colleagues from the CDRterra and CDRmare community. The assessment of feasibility and desirability, though interrelated, should be distinguished from one another also in order to prevent intransparency and miscommunication in how the research community contributes to wider societal debates; by informing societal and political decisions, rather than attempting to claim normative authority.

The evaluative scheme separates between two main areas of assessment:
(1) the process of the implementation of a CDR method (e.g., constraints and enablers for technological feasibility, political feasibility, and resource availability, as well as procedural fairness),
(2) the impacts of the implementation of a CDR method (e.g., climate effectiveness, cost effectiveness, impacts on individuals and society, impacts on non-human environment).

Similar to the descriptive scheme, also Tthe evaluative scheme is also hierarchically structured into evaluative dimensions and evaluative criteria. Evaluative criteria are used for the assessment by aggregating the information given by its indicator(s) and telling whether this is good or bad in certain regards, e.g. that state x is unfair according to standard y, or that it is effective in reaching goal y, or that y will not be (politically) feasible. A specific scheme is currently work in progress.