Carbon dioxide emissions from international air transport of people and freight: New Zealand as a case study

Abstract

International aviation accounts for over 2% of global emissions, but was not subject to Kyoto Protocol liabilities, and was not directly addressed by the Paris Agreement. Calculating emissions associated with individual countries is complicated, with data that is publicly available and free to access often being difficult to obtain. In this paper, a case study is presented where commercially sensitive fuel uplift is used to calculate New Zealand specific emissions factors of 0.81 kg CO2 per tonne km (CO2 per t-km) for short-haul and 0.79 kg CO2 per t-km for long-haul international aviation. This was used to estimate international aviation CO2 emissions associated with New Zealand in 2017 to be 8.4 Mt CO2 in total (2 significant figures, rounded down), with international visitor travel to and from New Zealand accounting for 4.3 Mt CO2, New Zealand residents’ international travel for 2.6 Mt CO2, exports for 0.72 Mt CO2, and imports for 0.89 Mt CO2 (all 2 significant figures, rounded up). Results show the fleet of aeroplanes which serviced New Zealand between 2007 and 2017 has become, on average, less efficient due to changes in operational factors such as seating density.