Aircraft emit carbon dioxide (CO2) and other greenhouse gases. The focus here is on CO2 emissions from passenger aviation. Emissions are measured by country and on a monthly basis. Data are from Amadeus IT Group in combination with ICAO emission factors. Due to the large numbers, the unit used here is MT (million tonnes).

Aviation passenger volumes are growing due to strong demand for travel

The Dashboard uses a unique approach to estimating total global passenger carbon dioxide emissions. To calculate emissions for each country, CO2 associated with all flights originating in a particular country were summed up. This includes both domestic and international trips. The logic for using  ‘origin of trip’ is that it helps to attribute the emissions of a particular itinerary (including  the whole trip from origin, via up to two transit points, to the destination) to a given country in a consistent way. The approach is a people-focused one (since the whole one-way journey is attributed to the country of departure); an alternative method would strictly allocate each individual take-off to the country where it occurred. The difference is that in the current Dashboard methodology, a flight from Sydney to London via Singapore will be fully counted towards Australia’s aviation emissions. In the alternative approach, the Singapore to London sector would be attributed to Singapore.

Data stem from the Amadeus booking database in combination with ICAO emission factors that are specific to each airport-airport pair. In 2016, ICAO updated their factors to take into consideration new aircraft types and more efficient technology. Amadeus data constitute a combination of actual bookings through the Amadeus platforms and modelled data to account for bookings made through other Global Distribution Systems.

Insights

  • The total carbon dioxide emissions from global passenger air travel in 2017 amounted to 586 Million tonnes. This represents an increase by 6.7% compared with the 549 Million tonnes emitted in 2016. The temporary decrease is likely due to changes in the emission factors and a break in the methodology.
  • IATA reports further statistics on passenger volumes, fuel consumption and CO2 emissions. These include both passenger and freight transport.
  • Air travel is growing fast and this is the main driver behind growing CO2 emissions. The efficiency per passenger kilometer is improving.
  • The peak of global passenger air travel emissions is in July and August due to high volumes from Northern Hemisphere holiday travel. Emissions in these two months alone were 110 Mt of carbon dioxide (18.8% of emissions in 2017).
  • First and business class travel only comprise 5% of all passenger travel, but the related carbon dioxide emissions amount to a share of 10%.
  • The Dashboard now provides aviation emissions by country, and it also shows a ranking of top emitting countries. The USA emits 22.9% of all passenger emissions, followed by China (10.5%).
  • As in 2015, the top regions in terms of aviation emissions are North America, Europe and South East Asia (including China).
  • Emissions are also shown per capita of population to provide a measure of dependency on air travel and also vulnerability to emission-related policies. Island nations are most exposed, as well as traditional long-haul destinations.