Field measurement
How We Measure Bark Methane Uptake
Crediting requires a site-wide methane uptake estimate with stated uncertainty. An independent auditor must be able to check the estimate, and the project must be able to repeat the measurement over time.
- 01
Plan the Field Measurements
We plan where to measure using the developer’s project boundaries, site descriptions, planting maps and species lists. On an initial visit, we check site access, conditions and trees, then adjust the plan.
- 02
Install Equipment and Measure Uptake
Crediting would require repeated measurements over years. We design and build the sampling equipment, install it across the site and train local crews to use it. Laser gas analyzers measure methane uptake at the bark. We record each reading and its quality checks for an auditor to review.
- 03
Measure Variation and Refine the Sampling Plan
Uptake varies across space, time, species, and other factors. Our proposed sampling plan starts with intensive measurements and several visits in the first year to quantify that variation. Later sampling would depend on the observed variation and uncertainty. The pilots will test whether targeted sampling can reduce field effort while meeting uncertainty requirements.
- 04
Estimate Uptake Across the Site
We use terrestrial laser scans to build a three-dimensional model of each site. We identify individual trees and calculate their woody surface area with methods we helped develop and publish. We combine that area with the methane measurements to estimate uptake across the site over time, including a confidence interval. A project could use this estimate under an approved crediting method. We report methane mass and state how we convert it to CO₂-equivalent units. Our GWP20 explanation describes that conversion and its limits.
Published science
Published Measurement Methods
Published studies show that forests take up methane through their bark. They also describe how to measure that uptake and use woody surface area to estimate it across a forest. Other research groups have confirmed the findings. The science page lists their studies.
Preparing the First Field Pilots
We are discussing candidate sites with developers and preparing the field measurement system and pilot terms. No pilot agreement has been signed. The pilot measurements will help us improve our estimates of how uptake varies across places and over time. The first crediting method will use these manual site measurements. We plan to test whether a digital method can reduce field effort while meeting uncertainty requirements. Crediting is still under development. Projects that begin measuring now can build a site record that could be assessed if the host project qualifies and a methane method is approved.