REDD projects aim to reduce greenhouse gas emissions resulting from deforestation or forest degradation in a specific project area. “REDD” refers to “Reducing emissions from deforestation and forest degradation”. Emission reductions are calculated by comparing the difference between: (a) baseline emissions (i.e., the emissions that would have occurred without the REDD project); and (b) actual emissions (i.e., the emissions that occurred with the REDD project). Verra registers REDD projects that meet its Verified Carbon Standard and issues carbon credits for projects that have successfully implemented and achieved emission reductions by reducing deforestation or forest degradation.
On 18 January 2023, the British newspaper the Guardian published an article that included sensational claims about the value of carbon credits issued by Verra for REDD projects. The same claims were mentioned in another article in Die Zeit. The article purported to be based on three scientific studies, one unpublished. Its key findings were based on calculations made by the journalists using results from the three studies. Verra’s Technical Review of the Guardian article and the studies found that the Guardian article and two of the three studies on which the article was based are patently unreliable.
Two of the studies were conducted by West et al., and the other by Guizar-Coutiño et al. All three studies relied on creating control areas, whose success depends on identifying relevant points of comparison and selecting geographic areas that are as similar as possible to a corresponding REDD project (Schleicher et al. 2019 and Desbureaux 2021).
The Technical Review found multiple failings in the West et al. studies, which make their conclusions patently unreliable, because they contain multiple serious methodological deficiencies. Specifically, they:
- Constructed their synthetic controls by looking at only a small set of superficial physical characteristics such as initial forest cover, slope, and proximity to state capitals, while excluding the key determinants of deforestation such as forest type, agricultural practices, and in fact any socioeconomic factors whatsoever;
- Selected geographic areas for their synthetic controls that were not facing any serious threat of deforestation, thereby underestimating the risk of deforestation in the REDD project areas;
- Selected too few geographic areas in composing their synthetic controls; and
- Used unsuitable data, including satellite imagery at a resolution of 250 meters x 250 meters (6.5 hectares), which is too crude for REDD projects, and much lower than Verra’s recommendation of a resolution of 100 meters x 100 meters, and a dataset from Global Forest Watch that scientists widely recognize should not be used to estimate deforestation or for REDD purposes without appropriate adjustments that the authors failed to make.
The Guardian focused its own “further analysis” on 29 of the 36 REDD projects reviewed in the two West et al. studies in order to reach a sensational conclusion that 94% of the credits from these projects should not have been issued. The journalists’ failure to publish this analysis is a breach of transparency and seriously undermines the credibility of their reporting, as unlike the scientific studies, these can not be reviewed.
In contrast to the Technical Review of the West et al. studies, Verra found the results of the third study, by Guizar-Coutiño et al., cited in the Guardian to be moderately reliable and a useful contribution to the literature. While the authors used higher resolution satellite data (30 meters x 30 meters), Verra found two deficiencies in the methodology. First, reliance on satellite data means on-the-ground data was overlooked. Second, the authors’ claim that the characteristics chosen to select their control areas reflect deforestation drivers is somewhat tenuous, given that these are highly location-specific. Once again, Verra’s REDD methodology emphasizes these for important scientific reasons.
According to Guizar-Coutiño et al., REDD project implementation was found to be associated with reductions in deforestation, with decreased deforestation in 34 sites and slightly increased deforestation in 6 sites. Collectively, these REDD+ projects reduced deforestation by 47% in the first five years. This rate of reduction was higher in high-deforestation countries and did not appear to be substantially undermined by leakage activities (i.e., deforestation being displaced to areas outside the REDD project area). The study concluded that, “Our results provide some room for optimism. Despite the many challenges to just and economically sustainable implementation, the initial wave of REDD+ projects were effective at reducing forest loss.”
The Guardian failed to report that the two methodologies reached largely different results, instead noting that “the data showed broad agreement on the lack of effectiveness of the projects compared with the Verra-approved predictions.” Major inconsistencies found by the Technical Review include that, of the 12 REDD projects in Brazil considered by both West et al. 2020 and Guizar-Coutiño et al., the former found that deforestation or degradation was lower in 33% of projects, whereas the latter found deforestation was lower in 92% and degradation in 75%.
Further, the Guardian grossly misrepresented the Guizar-Coutiño et al. findings in order to support the hypothesis drawn from the flawed West et al. 2020 and West et al. 2023 studies. The journalists, after converting Guizar-Coutiño et al.’s findings into emission reductions, compared these figures with the pre-project predictions of the project developers. The Technical Review found this to be a false comparison. For a variety of reasons, the pre-project predictions of project developers often overestimate what they actually achieve, and assume that everything works as planned. What the journalists should have done is to compare Guizar-Coutiño et al.’s findings with the actual emission reductions delivered by the projects. It is on this basis that Verra issues carbon credits, not on the basis of the predictions of project developers.
This document sets out Verra’s Technical Review of the following studies:
- Thales West et al., “Overstated carbon emission reductions from voluntary REDD+ projects in the Brazilian Amazon,” Proceedings of the National Academy of Sciences 117, no. 39 (September 14, 2020): 24188. (West et al. 2020)
- Thales West et al., “Action needed to make carbon offsets from tropical forest conservation work for climate change mitigation,” unpublished preprint (2023). (West et al. 2023)
- Alejandro Guizar-Coutiño et al., “A global evaluation of the effectiveness of voluntary REDD+ projects at reducing deforestation and degradation in the moist tropics,” Conservation Biology 36, no. 6 (17 June 2022): e13970. (Guizar-Coutiño et al.)
This document also sets out Verra’s Technical Review of statements made in the following media article about the above materials:
- Patrick Greenfield, “Revealed: more than 90% of rainforest carbon offsets by biggest provider are worthless, analysis shows,” Guardian (January 18, 2023). (The Guardian)
Verra makes the following findings.
First, the West et al. 2020 and West et al. 2023 studies are patently unreliable because they contain multiple serious methodological deficiencies, as explored in Section 4. Specifically, they:
- Ignored key factors in deforestation, including all socio-economic factors, when establishing their own baselines;
- Compared REDD projects to areas that likely were under no serious threat of deforestation;
- Relied on an insufficient number of comparison areas; and
- Used datasets widely known to be unsuitable for measuring deforestation, particularly for REDD projects.
Second, the Guizar-Coutiño et al. study is mostly reliable because it contains only minor methodological deficiencies, as explored in Section 5. Specifically, it:
- Used relevant, albeit simple, characteristics when establishing alternative baselines; and
- Used datasets that are reasonably suitable for measuring deforestation, though they do not replace on-the-ground analysis.
Third, the Guardian article is patently unreliable because it contains multiple serious methodological deficiencies, as explored in Section 6. Specifically, it:
- Failed to acknowledge the inconsistencies between the studies;
- Grossly misrepresented the Guizar-Coutiño et al. findings; and
- Used an unpublished and largely undisclosed methodology to interpret the studies.
3. Background and Key Concepts
The Technical Review relates to “REDD”, which refers to “Reducing emissions from deforestation and forest degradation”. A “REDD project” is an activity aimed at reducing emissions from deforestation or forest degradation in a specific geographic area.
In the REDD context, “emission reductions” refer to the quantity of emissions that a REDD project reduces over a period of time, equivalent to the difference between: (a) baseline emissions (i.e., the emissions that would have occurred without the REDD project); and (b) actual emissions (i.e., the emissions that occurred with the REDD project). An explainer for calculating emission reductions is in Table 1.
Table 1: Explainer for calculating emission reductions from a REDD project
|Emissions without the REDD project (baseline emissions)||Emissions with the REDD project (actual emissions)||Emission reductions|
|A forest is cut down, releasing 100 tonnes of carbon dioxide||A forest is conserved, preventing the release of any carbon dioxide||100 tonnes of carbon dioxide (i.e., 100 minus 0)|
|A large section of forest is cut down, releasing 50 tonnes of carbon dioxide||A small section of forest is cut down, releasing 10 tonnes of carbon dioxide||40 tonnes of carbon dioxide (i.e., 50 minus 10)|
Verra registers REDD projects that meet its Verified Carbon Standard. The process of registration includes the following steps:
- Project developers and their local partners identify deforestation patterns and risks existing in the project area and its surroundings (the reference region) based on information and their knowledge of local circumstances and socio-economic processes, gained primarily through extensive on-the-ground work;
- Project developers and their local partners calculate a baseline accordingly;
- The baseline is validated through independent third-party auditors, known as validation and verification bodies (VVB). VVBs themselves, must be independently accredited to ISO 14065 General principles and requirements for bodies validating and verifying environmental information by an International Accreditation Forum (IAF) member, before being approved by Verra to audit projects to the Verified Carbon Standard;
- Verra considers a request to register the project in line with the requirements of the Verified Carbon Standard.
Verra issues carbon credits to REDD projects that have been successfully implemented and have reduced deforestation or forest degradation. The process of issuance includes the following steps:
- Project developers and their local partners monitor whether deforestation occurred and its magnitude against the deforestation rate in the baseline and the way that actions aimed at preventing or reducing deforestation were implemented;
- Project developers and their local partners calculate emission reductions on this basis;
- The findings are verified by an independent expert auditor (i.e., a validation and verification body, as described above);
- Verra considers a request to issue carbon credits in line with the requirements of the Verified Carbon Standard, with each carbon credit representing one tonne of carbon dioxide that is not released into the atmosphere.
Verra issues carbon credits only after the emission reductions have been delivered (ex post crediting). Verra does not issue carbon credits based on the predictions of the project developers about how many emission reductions are likely to be achieved (ex ante crediting).
Verra at NACW