In a crucial advancement for climate policy and carbon markets, new research elucidates the importance of temporary carbon dioxide (CO₂) removals as strategic offsets for methane (CH₄) emissions. The study, published in Nature Climate Change, emphasizes the necessity of nuanced carbon accounting schemes that differentiate between permanent and temporary carbon storage, a gap that has long hindered effective implementation of nature-based solutions (NBS) and carbon offset initiatives. This pivot in understanding offers fresh perspectives for accelerating global emissions reduction efforts while addressing the unique atmospheric lifetimes and warming potentials of different greenhouse gases.
Carbon accounting, pivotal to informed climate action, has traditionally struggled with the challenge of quantifying the permanence of stored carbon. This problem is particularly acute for terrestrial biosphere projects, which dominate current CO₂ removal activities globally. These projects often involve forests or soil carbon pools that exhibit variability and potential reversibility over decades. The transient nature of such carbon storage is commonly referred to as carbon non-permanence and has historically impeded the integration of these solutions into carbon markets, due to concerns over credit validity and long-term climate benefits.
Efforts to mitigate non-permanence risks have led to innovatively designed buffer and risk-pool mechanisms, such as the Reversal Risk Buffer Pool Account under the Paris Agreement’s Crediting Mechanism. While these mechanisms safeguard permanent carbon credits, the new study advocates a shift in how temporary carbon removals are perceived. Instead of solely emphasizing permanence, the researchers argue that temporary carbon storage possesses intrinsic value for countering short-lived climate pollutants, especially methane, which has a far shorter atmospheric lifespan but significantly higher immediate warming impact.
Methane, with its roughly 12-year atmospheric half-life and a global warming potential about 28-36 times that of CO₂ over a 100-year period, poses unique challenges that permanent CO₂ removals cannot address as effectively on short timescales. The paper suggests that matching CH₄ emissions with temporary CO₂ removal projects—characterized by carbon pools that last several decades—can produce more accurate climate impact neutralizations. This temporal alignment reduces intergenerational burden disparities and alleviates contentious issues surrounding discount rates applied to future damages, which typically diminish the perceived urgency of reducing long-term emissions.
A significant revelation from the research is the baseline welfare equivalence between temporary and permanent CO₂ removals relative to methane emissions. Quantitatively, offsetting the warming effects of one ton of methane requires the removal of 87 tons of CO₂ stored temporarily over 30 years, as opposed to only 17 tons if removals are permanent. While this increases the volume of required temporary removals by a factor of five, it underscores the feasibility and economic attractiveness of leveraging short-term NBS projects, which often come with significantly lower costs, sometimes under $20 per ton of CO₂ and occasionally even offering negative net costs when co-benefits such as biodiversity and ecosystem services are factored.
However, the current carbon markets have struggled to fully capitalize on these low-cost nature-based removals due to uncertainties in long-term monitoring and verification, as well as fears of carbon release from forest fires, pests, or land use changes. These concerns have restricted growth in natural carbon offset markets despite rising buyer willingness to pay premiums for robustly validated removals. The proposed reframing of temporary removals as targeted solutions for methane emissions could enhance market credibility and attractiveness by aligning project valuation with actual climate impacts, facilitating a more nuanced and credible carbon trading framework.
An operational innovation suggested by the study involves adopting consistent monitoring periods of 30 years for temporary removal projects. This duration aligns with existing financial instruments such as government bonds and mortgages, making it a practical governance standard that balances the need for thorough verification with feasibility. Additionally, projects demonstrating continued carbon storage beyond 30 years could be recertified sequentially for subsequent intervals, enabling repeated compensation of methane emissions over time, thereby extending the utility and market eligibility of temporary removal projects.
Such dynamic contractual and monitoring arrangements would not only improve confidence among market participants but also reduce insurance costs, addressing key economic barriers to scaling temporary carbon removal initiatives. This approach is particularly relevant given that residual methane emissions, especially from sectors like agriculture, will likely persist well beyond 2100 and require effective offset solutions throughout the long-term transition to a net-zero economy.
Compelling economic arguments further strengthen the case for temporary removals. With recent estimates suggesting the social cost of methane exceeds $7,000 per ton, the deployment of temporary CO₂ removals to offset methane emissions becomes financially viable, even at scale and with conservative equivalence ratios. This contrasts sharply with the comparatively modest costs of many nature-based removal strategies, highlighting a substantial untapped opportunity to intensify climate mitigation efforts through efficient allocation of offset resources.
It is crucial to acknowledge, however, that temporary removals are complementary rather than substitutes for permanent carbon sequestration solutions. Permanent removals—such as geological storage, enhanced mineral weathering, or long-lived bioenergy carbon capture and storage—remain indispensable for fully neutralizing long-lived CO₂ emissions, which accumulate persistently in the atmosphere. The researchers advocate for the development of distinct and parallel carbon permit markets that recognize the divergent roles of temporary and permanent removals, enabling each to be deployed where most effective and economically rational.
This differentiated market structure could significantly enhance policy clarity by explicitly connecting the lifespan of carbon storage to the atmospheric challenge posed by specific greenhouse gases. Such alignment between environmental dynamics and economic instruments marks an important step toward the design of more transparent, effective, and equitable emissions trading systems.
Adoption of these insights at international climate negotiations, notably within frameworks like Article 6 of the Paris Agreement, which governs carbon markets and offsets, could accelerate harmonized accounting practices. This would facilitate linking of temporary removal credits to methane mitigation commitments, improving global emissions inventories, and encouraging investment in a broader portfolio of natural climate solutions.
In sum, the study reframes how the climate community considers temporal dimensions of carbon storage, emphasizing precision in matching mitigation strategies to the chemical and physical characteristics of greenhouse gases. By doing so, it unlocks substantial potentials within nature-based CO₂ removals, aligns economic incentives with climate realities, and furthers the effectiveness of net-zero pathways.
Such advancements offer promising avenues for policymakers and market actors to capitalize on the inherent strengths of temporary carbon removals, transforming a longstanding challenge into an opportunity for more targeted, credible, and scalable climate action.
This shift also calls for increased interdisciplinary collaboration among ecologists, economists, climate scientists, and legal experts to refine monitoring technologies, verification protocols, and contractual frameworks supporting these temporary schemes. Together, these efforts will be central to realizing the full potential of nature-based solutions within the evolving carbon market landscape.
Ultimately, embracing the temporal nuance of carbon storage and atmospheric lifetimes of greenhouse gases enriches our toolkit to confront climate change pragmatically and justly, paving the way for innovative policy mechanisms that can keep pace with the urgency and complexity of the climate crisis.
Subject of Research: Carbon accounting and mitigation strategies focusing on the temporal dynamics of CO₂ removals and methane emissions.
Article Title: Temporary carbon dioxide removals to offset methane emissions.
Article References:
Venmans, F., Rickels, W. & Groom, B. Temporary carbon dioxide removals to offset methane emissions. Nat. Clim. Chang. (2025). https://doi.org/10.1038/s41558-025-02487-8
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