Applying Equity Principles Leads to Higher Carbon Removal Obligations in Canada
This week, we deep dive into a paper recently published in Communications Earth & Environment. The study was led by Kasra Motlaghzadeh, from the Department of System Design Engineering of the University of Waterloo, and the Climate Intervention Strategies Lab in Waterloo (Canada).
This paper explores how integrating equity frameworks into climate burden-sharing models changes Canada’s obligations for carbon dioxide removal (CDR) at both national and global scales. More specifically, the authors investigate how different equity-based approaches (like per-capita fairness, historical responsibility, or capacity to act) would alter Canada’s implied CDR commitments relying on an integrated assessment model approach.
Relying on a customized version of GCAM (Global Change Analysis Model), the authors apply multiple burden-sharing principles, comparing the traditional “net-zero” pathways versus equity-informed alternatives, and examine Canada’s remaining carbon budgets and subsequent CDR needs through to the year 2100.
The paper evaluates three equity-based burden-sharing scenarios, each grounded in a distinct principle of climate justice. Under the “Capability” (CAP) scenario carbon removal responsibilities are based on countries’ financial and technological capacity, e.g. richer nations like Canada are expected to do more; under the “Equal Per Capita” (EPC) scenario every person globally has the same emissions entitlement, leading to higher obligations for countries with high per-capita emissions; finally, under the “Historical Responsibility” (CPC) responsibility is based on cumulative past emissions, requiring countries with a legacy of high emissions—like Canada—to offset a larger share. These equity scenarios are compared against a Net-Zero (NZ) baseline, where Canada only offsets its own remaining emissions.
Results show that under equity frameworks, there is substantially higher CDR demand, specifically nearly three times more (up to ~20.3 GtCO₂ vs. ~7.5 GtCO₂ under equity-based and traditional net-zero scenarios, respectively). In addition, findings highlight that Canada’s CDR portfolio—comprising bioenergy with carbon capture and storage (BECCS), direct air capture (DAC), and enhanced weathering—could reach a peak annual removal capacity of around 500 MtCO₂/year by 2100. In terms of feasibility, predicted yearly growth rates (2.8–16% per year) align with historical Canadian ramp-ups in sectors such as ammonia synthesis and biomass usage, suggesting that rapid CDR scale-up is possible, if supported by policy and infrastructure. Several socioeconomic and technological sensitivity tests—covering costs, uptake speed, and tech availability—consistently reinforced the conclusion: regardless of variables, CDR remains essential for Canada to discharge its carbon debt when equity is considered.
Here is a list of the main takeaways of this paper:
- Equity-based climate approaches, encompassing fairness principles like historical responsibility, triple Canada’s CDR burden up to 20 GtCO₂ by 2100.
- Achieving equity-aligned goals requires the aggressive deployment of CDR technologies at unprecedented scales, scaling up to gigaton levels.
- Annual CDR rates may need to exceed 500 MtCO₂ by 2100 to meet long-term obligations, which implies consistent, high growth rates sustained over decades.
- A rapid scale-up is technically feasible, based on past Canadian trends for similar industrial transformations in sectors such as ammonia and bioenergy.
- Policy frameworks must evolve to meet equity-driven targets: a coordinated action across governance, finance, and innovation is essential.
Read the full paper here: Applying Equity Principles Leads to Higher Carbon Removal Obligations in Canada