Calculate CO2 emissions for a flight itinerary using an emissions API

Steps

1. Integrate with an emissions estimation API (such as Atmosfair, ICAO Carbon Offset Calculator API, or Amadeus's Flight Choice Prediction with emissions data) by sending origin, destination, cabin class, and number of passengers.
2. Receive a CO2e (carbon dioxide equivalent) figure in kilograms per passenger; ensure the methodology (ICAO, myclimate, or similar) is disclosed to meet regulatory transparency requirements.
3. Display the emissions estimate inline with search results and at checkout; use simple visual comparisons (e.g., equivalent to X km driven) to make the figure meaningful.
4. For direct vs. connecting flight comparisons, surface the per-itinerary CO2e so travelers can factor in environmental cost alongside price and duration.
5. If you offer carbon offsetting, call an offset partner's API (e.g., Gold Standard project credits) to price an offset for the calculated CO2e and offer it as an optional add-on at checkout.
6. Log CO2e data per booking for corporate sustainability reporting; aggregate monthly and annual totals by department or cost center.