CORSIA recently approved Isometric’s biochar protocol. This is a good sign, but it does not mean airlines can buy or use biochar credits yet. The rules behind the system are still being built.

Here is what matters for anyone working with biochar:

• Approval is only the first step.

A protocol on a list does not unlock demand. Host countries must first approve each project and agree to adjust their climate reporting (this is the CA).

• Many governments are not ready.

Most countries do not yet know how to report durable removals like biochar. Without this, they cannot issue the approvals that CORSIA requires.

• There is still a debate on “outside NDC”.

Some experts say that if a project is clearly outside a country’s climate plan, it should not need a CA. Others say skipping the CA could create confusion or double counting. ICAO has not made a final decision.

• Airlines care about cost.

They will choose cheaper credits unless a rule or a reputation concern pushes them toward durable removals.

What needs to happen next:

• Clear rules from ICAO.

They need to say whether biochar projects outside a country’s climate plan can be used without a CA, or if every project will need one.

• Clear signals from governments.

Countries that want biochar investment must explain how they will treat durable removals in their national climate reporting.

• Early testing.

Countries and standards need to try small pilots now. These pilots will help build the reporting systems required for biochar credits to count under CORSIA.

For the biochar community, the main message is simple:

CORSIA is opening a door, but accounting rules will decide how fast we walk through it. Developers who align early with host-country rules will be in the strongest position once aviation demand grows.

Simple acronyms:

• CORSIA: The global system airlines use to reduce the climate impact of international flights.

• ICAO: The UN body that creates the rules for CORSIA.

• NDC: A country’s climate plan under the Paris Agreement.

• CA (Corresponding Adjustment): A correction a country makes in its national climate report to avoid double counting.