Permanence
A tonne of CO₂ avoided for one year is not the same as a tonne stored for a thousand. Permanence measures how durable a credit's climate benefit really is.
Permanence is the expected duration that emissions reductions or removals will be maintained. It covers physical reversal risk (fire, drought, pests, equipment failure) and intentional reversal risk (land-use change, project abandonment).
Modern frameworks express durability in tiers: short-term (decades), long-term (centuries) and geological (millennia).
If forest carbon burns down in year 30, the atmospheric benefit is reversed — but the buyer has long since claimed the offset. Without robust permanence safeguards, voluntary credits can systematically over-promise.
Buyers with science-based targets are increasingly steering toward higher-durability removals, while pricing nature-based credits separately.
Buffer pool coverage
What % of issued credits are held in a non-tradable buffer to compensate for reversals; we benchmark against VCS AFOLU norms (10–60%).
Risk rating
We map the project's documented risks (natural, financial, social, regulatory) into a 0–100 reversal-risk score.
Monitoring frequency
Remote-sensing cadence (annual minimum, ideally quarterly for forestry) and ground-truth verification intervals.
Durability tier
Each credit is tagged short-term (≤100 yr), long-term (100–1,000 yr) or geological (>1,000 yr) based on the storage medium.
- VCS AFOLU Non-Permanence Risk ToolThe buffer-pool methodology underpinning all Verra forestry, ARR and IFM credits.
- Puro Standard — Methodology suiteEngineered removals (biochar, BiCRS, geologically stored CO₂) with explicit durability tiers.
- ART TREES — Reversal Risk BufferJurisdictional REDD+ buffer-pool framework used by LEAF Coalition buyers.
- ICVCM CCP — PermanenceIndependent integrity criteria requiring monitoring, compensation and durability disclosure.
- Buffer pool below 10% for AFOLU projects.
- No documented compensation mechanism if reversals exceed buffer.
- Monitoring intervals longer than 5 years for nature-based projects.
- Durability claims unsupported by storage chemistry or land tenure.
- Single-developer buffer (no pooled risk-sharing across projects).