> ## Documentation Index
> Fetch the complete documentation index at: https://next-developers.opencard.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Environmental Impact

> Subscribe to OpenCard environmental impact webhooks for per-transaction CO₂ emissions and carbon social cost data delivered alongside card transaction events.

Subscribe to environmental impact webhooks per organization. Two optional providers — enable the flag that matches your OpenCard contract:

| Flag          | Event                              |
| ------------- | ---------------------------------- |
| `aland_index` | `environmental.impact.aland_index` |
| `deedster`    | `environmental.impact.deedster`    |

Both return the same payload shape:

```json theme={null}
{
  "carbon_emission_in_grams": 0.66,
  "carbon_social_cost_amount": 2.1,
  "carbon_social_cost_currency": "SEK",
  "transaction": { "id": "10", "card_issuer": "nordea" },
  "organization": { "reference_id": "client_acme_001" },
  "card_holder": { "reference_id": "employee_john_42" }
}
```

Also available via receipt scanner when `include: ["environmental_impact"]`.