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# init(carbonFootprint:)

Creates additional route information for carbon footprint.

```
convenience init(carbonFootprint: Measurement<UnitMass>)
```

## Parameters

`carbonFootprint`

A measurement of carbon emissions using @c NSUnitMass. Typical units include:

- @c NSUnitMass.grams for small emissions (e.g., short trips, efficient vehicles)
- @c NSUnitMass.kilograms for larger emissions (e.g., long journeys, less efficient vehicles)

## Return Value

A new @c CPRouteDetail instance representing the carbon footprint

## Discussion

Use this method to display the estimated carbon emissions for the route. This helps
environmentally-conscious users evaluate and compare the environmental impact of different
route options.

\discussion The system formats the measurement with appropriate units and precision. Measurements
in grams display with the ‘g’ suffix, while measurements in kilograms use ‘kg’. The measurement
is automatically formatted as CO₂ in the UI (e.g., “2.5 kg CO₂”). The system may round values
for display clarity.
\note Apps should calculate carbon footprint based on vehicle type, fuel efficiency, route distance,
terrain, and traffic conditions. Electric vehicles may show reduced or zero emissions compared
to combustion vehicles, depending on the regional electricity generation mix. Consider
providing methodology information in your app’s settings or help documentation.

---

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