As we count down to the 4th International Conference on Carbon Dioxide Removal in Milano, we are hosting a series of discussions on the research that will be shaping our sessions this June! 
This research introduces a physically consistent accounting framework 
for temporary Carbon Dioxide Removal 
, arguing that temporary carbon storage 
should not be treated as equivalent to permanent removal for offsetting fossil CO₂ emissions 
. Instead, the authors demonstrate that temporary CDR can play a meaningful mitigation role 
by compensating for short-lived climate forcers such as methane 
, providing a more scientifically grounded approach 
to climate accounting and carbon crediting 
in hard-to-abate sectors like agriculture 
.
Read the full paper here: Link 
Are we overestimating the climate value of temporary carbon removal by comparing it to permanent storage? 
Full Abstract: Accounting for temporary carbon dioxide removal and its ability to offset short-lived climate forcers
Authors: ThomasGasser YueHe MathewsGidden ShilongPiao TaoWang KeywanRiahi
Temporary carbon dioxide removal (CDR) arguably dominates currently deployed CDR capacity, while permanent CDR options face persistent feasibility, scalability, and cost barriers. Greenhouse gas accounting frameworks have been suggested to integrate temporary CDR using equivalency assumptions that treat temporary and permanent storage as interchangeable. Such assumptions conflict with physical climate science because stored carbon is eventually re-released, and temporary CDR cannot fully compensate for fossil CO₂ emissions in the way permanent CDR can. Here, we propose an alternative and physically consistent accounting for temporary CDR – one that highlight a potential role for it in climate mitigation strategies. Rather than offsetting CO₂ emissions, temporary CDR can effectively compensate for non-CO₂ climate forcers, particularly short-lived species whose warming impacts are inherently transient. Using a impulse-response-based framework, we quantify compensation ratios linking temporary CO₂ storage durations to emissions of short-lived forcers. We find that these ratios are relatively insensitive to the choice of time horizon, enhancing their robustness for policy applications. For example, compensating the climate impact of 1 kg of CH₄ emissions requires approximately 498 kg of CO₂ stored for 20 years (e.g., in bioplastics) or 101 kg of CO₂ stored for 100 years (e.g., in durable wood products). We further identify a critical lifetime threshold that distinguishes short-lived from long-lived climate forcers with respect to the suitability of temporary CDR compensation. Applying this threshold enables clear differentiation between emissions that can be meaningfully compensated by temporary storage and those that require permanent mitigation measures. Policy implementation of this framework requires explicit, differentiated reporting of short-lived and long-lived emissions categories, along with transparent accounting of storage durations. This approach enables scientifically grounded crediting of temporary CDR, particularly in sectors such as agriculture where non-CO₂ emissions dominate and direct emission reductions remain extremely challenging. By aligning climate accounting with physical climate dynamics and UNFCCC accounting, this framework avoids false equivalence while unlocking a realistic and valuable mitigation role for temporary CDR.