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.
- The total carbon dioxide emissions from global passenger air travel in 2017 amounted to 591 Million tonnes, and this has increased to 665 Mt in 2018. This represents an increase of 12.5%. Note that the latest aircraft efficiency gains are not taken into account as emission factors provided by ICAO lag behind by several years.
- 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, but average distance is increasing as well.
- 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 126 Mt of carbon dioxide (18.9% of emissions in 2018).
- First and business class travel only comprise about 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 22.7% of all passenger emissions, followed by China (10.4%). Emissions from India are growing fast, now making up 3.5% of aviation passenger emissions.
- 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. The Maldives, for example, has a theoretical aviation carbon footprint per head of population of 1,576 kg CO2. Singapore’s per capital aviation emissions are 1,047 kg of CO2.