Carbon Footprint Map - Air Travel
See how much CO2 your flying puts in the air
"By calculating the distance between your origin and destination city, based on their latitude and longitude. This is a standard trigonometric calculation. If you wish to calculate the effect of stopovers, simply enter the legs of the flight as separate trips.
Next you are categorised by flight as a short, medium, or long-haul trips. Because planes burn more fuel at takeoff and landing than at cruising altitude, short-haul trips are less fuel-efficient per mile flown.
For each of the three types of trips, a different carbon index that indicates the amount of fuel burned, on average, per mile of the journey. By multiplying this index by the distance of your trip, it is calculated how much fuel was burned per passenger for that particular flight."