In an article recently published at Climate Policy, ‘Legal Guardrails on States’ Dependence on Carbon Dioxide Removal to Meet Climate Targets’, a group of authors led by Lavanya Rajamani have studied states’ utilization of CDR measures in their climate objectives and set out safeguards against their inadequate use.
Key takeaways:
- Use of CDR presents flexibility advantages. First, it can decrease the global temperature to a certain level following a temporary overshoot. Second, it can maintain temperature increase at a given degree while permitting the release of more GHGs. While all emission reduction pathways make use of these flexibilities, the degree of use is significantly divergent across pathways. Increased use of the flexibility options renders overshooting the temperature goal of 1.5 ° C more likely.
- Temperature overshoot, in turn, increases the possibility of occurrence of highly severe events whose effects are not fully reversible. These impacts include deaths, economic damages and impairment of ecosystems.
- Some CDR activities may not be realized due to technological barriers or release of sequestered carbon. Pathways with more ambitious emission reduction plans mitigate CDR-related risks.
- Notwithstanding the significance of adopting a stringent approach when using CDR, most climate targets adopted by states excessively utilize CDR and do not fully reveal the degree of utilization and how CDR activities will be realized.
- States have a due diligence duty to guarantee that activities within their territories or control do not inflict harm upon the environment of other states or areas not under the control of states. The obligations flowing from this duty are setting-dependent. When applied within the context of the duty to counter climate change, the due diligence duty imposes strict requirements in view of the scientific findings revealing irreversible climate damage in cases where global temperature increase exceeds 1.5 ° C, a scenario that will likely unfold in the near future. Developed states have more stringent obligations compared to non-developed states due to possessing greater capabilities.
- States should be fully transparent in relation to the CDR measures they plan to take and engage in consultations with other states prior to including them in their targets.
- States should decrease the impacts and duration of an eventual temperature overshoot to the extent possible and take steps towards returning to 1.5°C.
- Given that there are ambiguities in relation to the potential of engineered and natural CDR methods, states should not use CDR as a replacement for emission reductions. In view of the difficulties in achieving emission reductions in some sectors such as livestock farming and aviation, steps should be taken to reduce demand.
- States should only make use of engineered CDR methods such as bioenergy with carbon capture and storage (‘BECCS’) and direct air carbon capture and storage (‘DACCS’) in their climate targets if they take steps towards ensuring their realization such as technology development, establishment of physical infrastructure for the transfer of CO2 and determination of adequate storage facilities. In addition, states should not make irrational estimations regarding the potential of natural CDR methods given land constraints.
- States should account for the measures they need to take to tackle the adverse impacts of CDR methods in their climate targets. For instance, DACCS may reduce the energy available for emission reductions and biomass used for BECCS can affect land carbon sinks.
- States should not excessively rely on CDR methods that lack permanence to make up for current GHG emissions that remain in the atmosphere for long periods.
- National measures geared towards countering climate change should be prioritized over financing emission reductions and removals abroad as the latter course of action can pose risks in cases where carbon markets are not adequately governed.
- States should clearly distinguish between the contribution of emission reductions and removals to their climate targets.
- States should divide the GHGs for which they provide estimations by sector and gas type to contribute to the realization of their CDR goals.
- States should specify the different CDR methods they aim to implement given the different challenges they pose as well as their divergent permanence.
- States should specify the methods and assumptions utilized for quantifying GHG emissions and removals.
- States should set out whether or not they rely on emission reductions and removals realized abroad.
Read the full paper here: https://www.tandfonline.com/doi/full/10.1080/14693062.2025.2599861