Durability-Permanence

Durability & Permanence Durability (often used interchangeably with permanence) is the expected time that a tonne of carbon dioxide, once removed from the atmosphere, stays out of it. It is the single variable that most cleanly separates a nature-based credit priced in the low tens of dollars from an engineered credit priced in the high hundreds — and it is the variable that determines whether a corporate buyer can defensibly count a purchase against a net-zero claim. As Fankhauser et al. (2021) argue, “net zero” is only coherent if residual emissions are matched with removals of comparable longevity; a fossil CO₂ molecule released today and a soil-carbon credit that reverses in 30 years do not cancel out in any physically meaningful sense. ...