Captain Drawdown’s daily logbook on every CDR story, paper, and expert voice — so you don’t have to read them all.
The story in one paragraph
A new paper in Communications Sustainability, part of the Nature portfolio, proposes throwing out the way the carbon market sorts its products. Instead of labeling credits as avoidance, reduction, or removal, the authors argue projects should be classified by the physical carbon-cycle mechanism they act on: preventing a flux of CO2, protecting an existing carbon pool, or enlarging a pool (Mechanism-based framework enables consistent assessment of carbon offsetting projects). That sounds like taxonomy housekeeping. It is not. It is a rubric that would let corporate buyers judge every credit by what it physically does to the carbon cycle, something the old three-bucket system has never delivered.
The mechanism
The paper’s core claim is that the familiar labels obscure the science. Two projects can both carry an “avoidance” tag while relying on completely different physical processes and completely different failure modes. One depends on a counterfactual about deforestation that never happens. Another depends on assumptions about fuel use in household stoves. The label says they are the same product. The biogeochemistry says they are not.
The framework replaces the label with a question: what pool or flux is this project acting on, and how do we measure the change? A forest protection project defends an existing carbon pool. Enhanced rock weathering, where crushed silicate rock reacts with CO2 and locks it into minerals, enlarges a pool (our primer explains the chemistry). Once you frame projects this way, the right measurement approach, the right permanence expectation, and the right reversal risk all follow from the mechanism itself.
The evidence chain backing this matters. A University of Cambridge analysis found that millions of credits from forest preservation projects were generated by overestimating how much deforestation would have occurred without them (Millions of credits generated by overestimating forest preservation). All those projects shared one label. What they actually shared was a fragile counterfactual about the same carbon pool. A mechanism-based lens is built to catch exactly that.
There is a second, quieter piece of evidence. New global estimates put plant CO2 uptake nearly one third higher than models assumed ([Plant CO2 uptake rises by nearly one third in new global
Citations
- Nature — Mechanism-based framework enables consistent assessment of carbon offsetting projects — research paper
- Sciencedaily — Millions of credits generated by overestimating forest preservation