Discounting emissions from temporarily stored carbon creates false claims on contribution to cumulative emissions and temperature alignment

Realising the social value of impermanent carbon credits

“…The next stage of the PACT framework links this additionality-based understanding of when impermanence arises with an assessment of the value of impermanent reductions in atmospheric greenhouse gases. One view is that if the policy goal is to achieve a time-bound target for limiting temperature increases, any drawdowns of carbon which reverse completely before that target date will not affect temperature at that point and so have limited value (except perhaps in helping the development of more permanent storage technologies) 21 . We take a different position 22 .…”

“…If successful, these actions would enhance project additionality, reduce risks of leakage of forgone production and hence emissions elsewhere, and improve local livelihoods. Continued monitoring would also enable separate, ongoing accounting of the physical climate impacts of projects (essential for tracking progress towards temperature-based goals 21 ). Crucially, this monitoringif linked, as we propose, with ex post repayment for lower-than-anticipated releases -incentivises project stakeholders to continue to safeguard already-credited carbon into the future.…”

Carbon accounting without life cycle analysis

“…For example, the value of temporary sequestration is still debated. [37][38][39] The shorter the time preference, the higher the value of temporary sequestration. 40 For example, in their LCA of building materials, Mequignon et al had to settle on a time preference to calculate the carbon footprint of building materials and how they are affected by the lifespan of the building.…”

Realising the social value of impermanent carbon credits

“…The next stage of the PACT framework links this additionality-based understanding of when impermanence arises with an assessment of the value of impermanent reductions in atmospheric greenhouse gases. One view is that if the policy goal is to achieve a time-bound target for limiting temperature increases, any drawdowns of carbon which reverse completely before that target date will not affect temperature at that point and so have limited value (except perhaps in helping the development of more permanent storage technologies) 21 . We take a different position, and consider temporary drawdowns as valuable 22 .…”

“…Moreover, by being explicitly geared towards frequent low-cost analysis of remotely derived data, the PACT framework offers the twin prospects of greater accountability for offset buyers and reduced transaction costs of project proponents, as well as aligning directly with calls for digital Monitoring, Reporting and Verification in carbon markets 30 . Continued monitoring would also enable separate, ongoing accounting of the physical climate impacts of projects (essential for tracking progress towards temperaturebased goals 21 ). Crucially, such monitoring -if linked, as we propose, with ex post repayment for lower-than-anticipated releases -incentivises project stakeholders to continue to safeguard already-credited carbon into the future.…”