Behind the Scenes at SB62: Inside the 2025 Bonn Climate Change Conference
30 June 2025
Slow Progress is No Progress: Methane Matters in Accelerating Climate Action
10 July 2025
By Femke Bosch
Our earth’s atmosphere is like a bathtub at risk of overflowing. In this analogy, the water in the bathtub represents a continuous influx of greenhouse gas emissions that cannot be adequately drained. The latest IPCC AR6 concludes that addressing this imbalance and limiting global warming to the 1.5°C benchmark requires reaching Net Zero around 2050 (IPCC, 2022). The ‘net’ component indicates that we must not only turn off the faucet – i.e., reduce CO2 emissions – but also expand the size of the drain. Currently, natural processes sequester carbon at an insufficient rate to ‘unclog’ this drain. However, there is hope that innovative methods and techniques can increase the number of Net Removals in the future.
In this context, the IPCC presents Carbon Dioxide Removal (CDR)[i] as the unavoidable tool in attaining Net Zero (IPCC, 2022). The exact scale of required CDR deployment varies and depends on the occurrence of an early phase-out of emissions. Current 1.5°C-compatible scenarios with no or limited overshoot require a significant average removal of 670 GtCO2 over this century (IPCC, 2018a). This amount is equivalent to over sixteen years of cumulative CO2 emissions (Grant et al., 2021). Despite this substantial requirement, there is still a long way to go. Modeling scenarios that limit warming to acceptable levels require doubling conventional CDR on land[ii] by 2050. The numbers are significantly higher for novel CDR techniques[iii], where deployment must increase by a factor of 1,300 by 2050 (Smith, et al., 2023).
In the face of such required scale-up rates, policymakers should read the recent IPCC scenarios as a wake-up call. First and foremost, it is crucial to ensure deep emission cuts and follow pathways that limit the role of CDR to feasible levels to prevent amplifying the magnitude of the gap (Grant, et al., 2021). For example, targeting demand-side mitigation is an important strategy to address the root of the problem and reduce reliance on scaling technologies. Second, well-designed policy instruments and effective governance are needed to ensure genuine progress in CDR efforts (Bright & Lockwood, 2022). Mapping the realities of scaling CDR requires accelerating research and development, developing tools for risk assessment, and establishing measurement, reporting, and verification frameworks.
As an institution that monitors the state-of-the-art of climate change knowledge, the IPCC also has its role to play in alerting the scientific community to the necessity for further studies on CDR. Current CDR research is dominated by natural and physical sciences[iv], is centered on a limited set of methods[v], and lacks a regional focus[vi]. Effective policy action should be facilitated by comprehensive research that accounts for the social realities around CDR. While curtailing emissions and closing the tap remains paramount, it is also crucial to deepen our understanding of the realities around expanding the capacity of the drain.
[i] Defined by the IPCC as “Anthropogenic activities removing CO2 from the atmosphere and durably storing it in geological, terrestrial, or ocean reservoirs, or in products.” (IPCC, 2018b).
[ii] Conventional CDR refers to CDR methods on land, covering reforestation, afforestation, and forest management (Smith, et al., 2023).
[iii] Novel CDR refers to techniques that are generally less mature, covering amongst others bioenergy with carbon capture and storage (BECCS), direct air carbon capture and storage (DACCS), and enhanced rock weathering (Smith, et al., 2023).
[iv] Research on CDR constitutes only 4% of English-language climate change related academic literature. Only 3% of these scientific studies are issued in social science journals (Smith, et al., 2023).
[v] BECCS and DACCS are significantly understudied, whereas methods such as biochar, soil carbon sequestration and forestation make up 80% of the literature (Smith, et al., 2023).
[vi] Only 1/3 of the scientific CDR literature identifies a geographical focus (Smith, et al., 2023).
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