REDD+ Prefeasibility Methods

The LandOS REDD+ Prefeasibility tool provides a streamlined estimate of potential Verified Carbon Units (VCUs) for projects following Verra’s VM0048 (Reducing Emissions from Deforestation and Forest Degradation, v1.0) and its corresponding modules and tools, such as VMD0055 (Estimation of Emission Reductions from Avoiding Unplanned Deforestation, v1.1) and VT0007 (Unplanned Deforestation Allocation: UDef-A, v1.0).

Within the VM0048 framework, GHG emission reductions are estimated by first analyzing jurisdictional historical activity data over a 10-year historical reference period (HRP), quantifying observed unplanned deforestation, and projecting the annualized rate onto stable forest to derive baseline activity data (AD) for the baseline validity period (BVP). Next, the tool allocates the jurisdiction’s AD proportionally to pixel-level risk and extracts the project area’s allocated AD. With the allocated AD in hand, LandOS estimates baseline GHG emissions by pairing the allocated hectares per year with IPCC-consistent emission-factor derivations and a user-chosen post-deforestation pathway (Eq. 1). Finally, the tool applies consistent deductions (Eq. 2, Table 1): leakage displacement, project emissions/efficiency, non-permanence buffer, and activity-data uncertainty, to translate baseline emissions into pre-feasibility VCU ranges.

$$\begin{aligned} \text{Baseline emissions} = \text{Allocated unplanned deforestation (AD)} \times \text{Emission factor} \end{aligned}$$ $$\begin{aligned} \text{VCU potential} = &\, ((\text{Baseline Emissions} - \text{Uncertainty}) \\ &\, - \text{Project Emissions} - \text{Leakage discount}) \\ &\, \times (1 - \text{Buffer Discount}) \end{aligned}$$

Table 1. Default Applied Discounts.

Under VM0048, Verra provides the deforestation-risk allocation for a project area based on a curated, third-party-reviewed implementation of VT0007, enabling developers to perform estimations. Verra publishes two types of data: (1) provisional allocated deforestation-risk data, intended to help project proponents conduct due diligence and explore feasibility; and (2) final allocated deforestation-risk data, released once the VMD0055-compliant data has passed the required third-party review (Allocated Deforestation Risk Maps: Timetable).

Depending on the project stage and datasets available for a region, LandOS REDD+ Prefeasibility computations get the allocated unplanned deforestation and emission factor from different data sources. Where Verra provisional or final allocation risk data is available, that is used through the “REDD+ Prefeasibility (Verra)” computation. When that is not available, the Unplanned Deforestation Allocation (UDef-A v1.0) benchmark model (VT0007) is used to generate risk allocation using Hansen data via the “REDD+ Prefeasibility (Hansen)” computation. Enterprise users can access the VT0007 alternative models for risk allocation using Hansen, MapBiomas, or JRC datasets (see separate documentation on REDD+ Prefeasibility Methods - Enterprise).

The VT0007 is Verra's tool to give a structured and transparent approach to generate benchmark risk maps for unplanned deforestation, compare and select among the benchmark and alternative risk models, and allocate jurisdictional deforestation expectations or emissions to projects proportionally to pixel-level risk giving “risker” pixels more baseline allocation. This helps align project-level baselines with jurisdictional activity, maintain consistency and integrity, and reduce arbitrary allocations. Prior to VT0007, there was a challenge in REDD+ projects over how to fairly and defensibly allocate the expected baseline deforestation to multiple project areas when jurisdictional baselines or Forest Reference Emission Levels (FRELS) are defined at broader scales.

REDD+ Prefeasibility (Verra) - Starter Tier

Risk Map

Where Verra has released provisional or final allocations for a project's jurisdiction, we estimate VCU potential using the Verra Allocated Deforestation-Risk Map. Provisional data are suitable for prefeasibility and early due diligence to explore whether the VM0048 REDD methodology would work; final data are intended for crediting. Significant divergences have been observed between Verra's provisional and final datasets, as well as in the results derived from them.

VCU Estimation

VCUs are estimated from the Verra Allocated Deforestation-Risk Map by pairing allocated deforestation with an emission factor and applying consistent deductions (leakage displacement, project emissions/efficiency, non-permanence buffer, and activity-data uncertainty). Expected annual deforestation (ha/yr) within the project area is computed as the sum, over project pixels, of the annualized baseline deforestation density (ha/pixel/yr) from the adjusted allocated-risk map. The emission factor (tCO₂e/ha) is derived by combining tree biomass within the project area (from global biomass datasets) with the default post-deforestation IPCC-based carbon stock determined by the user-defined post-deforestation pathway.

By integrating spatially explicit deforestation risk with standardized emission assumptions, the tool translates forest cover and risk profiles into indicative estimates of avoided emissions. Users can evaluate potential areas, compare scenarios, and prioritize interventions consistent with VM0048.

The tool is designed for early-stage planning and screening, providing rapid insight into potential VCU outcomes before field data or site-specific emission factors are introduced. It focuses on Verra provisional and final risk maps and default emission factors to maintain accessibility and comparability across regions within the VM0048 framework. This is an indicative result and can be refined with further work at the feasibility stage to customize the emission factor with project specific data and considerations.

REDD+ Prefeasibility (Hansen) - Starter Tier

Risk Map

For jurisdictions where Verra has not released allocated risk maps for VM0048, we produce an estimate of the VUC potential based on an in-house VT0007 (UDef-A) benchmark allocated risk map implementation. In this particular computation, the Hansen et al 2013¹ dataset is used. This approach allows the calculation of the adjusted allocated risk maps via a geometric decay function based on distance from the forest edge.

The historical reference period used by VT0007 is defined to allocate the unplanned deforestation, a 10-year window ending the year before the project start date. In this step, available data is evaluated for gaps. Then a forest/non-forest mask and subsequent distance to non-forest map are generated. Forest area in the Historical Reference Period (HRP) is evaluated at set time points and the annual deforestation rate and summary statistics for the jurisdiction are computed.

VCU Estimation

VCUs are estimated from the in-house Hansen-based Benchmark Allocated Deforestation-Risk Map by pairing allocated deforestation with an emission factor and applying consistent deductions (leakage displacement, project emissions/efficiency, non-permanence buffer, and activity-data uncertainty). Expected annual deforestation (ha/yr) within the project area is computed as the sum, over project pixels, of the annualized baseline deforestation density (ha/pixel/yr) from the adjusted allocated-risk map. The emission factor (tCO₂e/ha) is derived by combining tree biomass within the project area (from global biomass datasets) with the default post-deforestation IPCC-based carbon stock determined by the user-defined post-deforestation pathway.

By integrating spatially explicit deforestation risk data with standardized emission assumptions, the tool translates forest cover and risk profiles into estimates of avoided emissions. Users can evaluate potential areas, compare scenarios, and prioritize interventions with an eye toward VM0048.

The tool is designed for early-stage planning and screening, providing rapid insight into potential VCU outcomes before field data or site-specific emission factors are introduced. It focuses on provisional risk maps and default emission factors to maintain accessibility and comparability across regions within the VM0048 framework. This is an indicative result and can be refined with further work at the feasibility stage to customize the emission factor with project specific data and considerations.

REDD+ Prefeasibility (Hansen) - Enterprise Tier

Risk Map

For jurisdictions where Verra has not released allocated risk maps for VM0048 and users are at the Enterprise Tier, we produce an estimate of VCU potential based on an in-house VT0007 Alternative model allocated risk map using Hansen data. The Verra VT0007 Tool has approaches for developing a benchmark (simplest) deforestation risk model and then alternative models which are evaluated systematically to find the most appropriate baseline deforestation risk map. The “starter tier” REDD+ Prefeasibility options do not enable the user to evaluate alternative models, but the “enterprise tier” does.

Alternative models are developed in a two stage approach: model fit for testing and then predictions used for testing. The testing stage is used to select among a benchmark model and at least two alternative models based on their assessed performance. The model is fit across the HRP and predictions occur across the BVP.

Alternative models are built using covariates to capture the accessibility, land-use pressure, and biophysical constraints that may inform deforestation risk including distance to built areas, water bodies, roads, pasture, croplands, and slope.

Training and testing alternative models can take time and so there may be a time delay between running this computation and receiving results.

VCU Estimation

VCUs are estimated from the in-house Hansen-based Alternative-models Allocated Deforestation-Risk Map by pairing allocated deforestation with an emission factor and applying consistent deductions (leakage displacement, project emissions/efficiency, non-permanence buffer, and activity-data uncertainty). Expected annual deforestation (ha/yr) within the project area is computed as the sum, over project pixels, of the annualized baseline deforestation density (ha/pixel/yr) from the adjusted allocated-risk map. The emission factor (tCO₂e/ha) is derived by combining tree biomass within the project area (from global biomass datasets) with the default post-deforestation IPCC-based carbon stock determined by the user-defined post-deforestation pathway.

By integrating spatially explicit deforestation risk data with standardized emission assumptions, the tool translates forest cover and risk profiles into estimates of avoided emissions. Users can evaluate potential areas, compare scenarios, and prioritize interventions with an eye toward VM0048.

The tool is intended to support early-stage project planning and screening, providing rapid insights into potential VCU outcomes before more detailed field data or site-specific emission factors are incorporated. Ito focuses on provisional maps and default emission factors to ensure accessibility and comparison across regions aligning with Verra’s VM0048 methodological framework. This is an indicative result and can be refined with further work at the feasibility stage to customize the emission factor with project specific data and considerations.

Footnotes

1. Hansen, M. C., P. V. Potapov, R. Moore, M. Hancher, S. A. Turubanova, A. Tyukavina, D. Thau, S. V. Stehman, S. J. Goetz, T. R. Loveland, A. Kommareddy, A. Egorov, L. Chini, C. O. Justice, and J. R. G. Townshend. 2013. High-Resolution Global Maps of 21st-Century Forest Cover Change. Science 342 (15 November): 850-53. Data available on-line from: https://glad.earthengine.app/view/global-forest-change. ↩