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Overstated carbon emission reductions from voluntary REDD+ projects in the Brazilian Amazon

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West, Thales 
Börner, Jan 
Sills, Erin 


Reduced Emissions from Deforestation and forest Degradation (REDD+) has gained international attention over the past decade, as manifested in both United Nations policy discussions and hundreds of voluntary projects launched to earn carbon-offset credits. There are on-going discussions about whether and how projects should be integrated into national efforts under the Paris Agreement. One consideration is whether these projects have generated additional impacts over and above national policies and other conservation measures. To help inform these discussions, we compare the crediting baselines established ex-ante by voluntary REDD+ projects in the Brazilian Amazon to counterfactuals constructed ex-post based on the quasi-experimental synthetic control method. We find that the crediting baselines assume consistently higher deforestation than counterfactual forest loss in synthetic control sites. This gap is partially due to decreased deforestation in the Brazilian Amazon during the early implementation phase of the REDD+ projects considered here. This suggests that forest carbon finance must strike a balance between controlling conservation investment risk and ensuring the environmental integrity of carbon emission offsets. Relatedly, our results point to the need to better align project- and national-level carbon accounting.



carbon credit, deforestation, impact evaluation, payment for environmental services, synthetic control, Brazil, Carbon, Climate Change, Conservation of Natural Resources, Forests, Greenhouse Gases

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Proceedings of the National Academy of Sciences of the United States of America

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Proceedings of the National Academy of Sciences


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