Calculating Flight Emissions

TABLE OF CONTENTS

• A case study:

Upon entry of the start and end point of your flight, Carbonhound will generate the distance of the flight with the Great Circle Distance methodology:

The Great Circle Distance Equation:

Due to the curvature of the earth, a two-dimensional measurement of the distance is flawed. To take into consideration of the altitude of travelled by the planes and the three dimensionality of the flight, we utilize the equation below:

      d = rcos^-1[cos a *cos b *cos(x-y) + sin a *sin b]

Looks daunting? Don’t worry, we will break it down for you.

‘d’ represents the distance between the two points

‘r’ : the earth’s radius

‘a’ & ‘b’ represent the latitudes of your starting and end point respectively

‘x’ & ‘y’ represent the longitudes of your starting and end points respectively

After the distance is derived, then the CH’s algorithm will multiply that by the corresponding emission factor to get the emissions being generated.

A case study:

Let’s say I am a Carbonhound user and I want to find the distance between Toronto Pearson International Airport (YYZ) and Vancouver’s international airport (YVR).

Step 1: Determine the coordinates of the two locations

Pearson’s International Airport: (43.6777° N, 79.6248° W)

Vancouver’s International Airport (49.1967° N, 123.1815° W)

Step 2: Apply the equation above

According to NASA, the earth’s equatorial radius is 6378 kilometers.

 d = 6378 km*cos^-1[cos (43.6777) *cos(49.1967)  *cos(123.1815-79.6248) + sin (43.6777) *sin (49.1967)] 

Step 3: Apply Emission Factors:

Emission factors vary depending on the distance of your flight and your travel class (economy, business and travel).

For this particular flight, the emission factor is 0.14615 kg CO2e/ km

Emission=0.14615 kgCO2e/km *3361 km 

Emission=491.21kg CO2e

 Emission=0.491 tons