We have uploaded a preprint of our 4C paper on valuing impermanent carbon credits, by using the Social Cost of Carbon as a basis for a discount function into the future. Comments and feedback are most welcome. This work tackles one of the biggest challenges in nature-based climate solutions: how to value carbon sequestration that might not be permanent. We developed a novel framework that conceptualizes permanence as additionality over time relative to a counterfactual baseline, uses risk-averse estimation of future carbon release, and deploys post-credit monitoring to correct for overly pessimistic forecasts. Our preliminary comparisons suggest that even after fully adjusting for impermanence, nature-based interventions may offer less costly ways of reducing climate damages than more technological solutions.