Click here for the full report.
Aviation emissions currently account for 2 to 2.5% of global CO2 emissions. Scenarios of future aviation project strong increases in air traffic and therefore emissions (UNEP Bridging the Emissions Gap).
The International Civil Aviation Organization (ICAO) has set a number of ‘goals’ for the environmental performance of international aviation: (1) a global annual average fuel efficiency improvement of 2 per cent until 2020 and an aspirational global fuel efficiency improvement rate of 2 per cent per annum from 2021 to 2050; (2) a medium term global aspirational goal of keeping the global net carbon emissions from international aviation from 2020 at the same level. Additionally, the US, Canada and Mexico have previously proposed a more ambitious, global goal to achieve a collective global goal of carbon neutral growth by 2020 based on a 2005 baseline, while Europe has proposed a 10% reduction by 2020 compared to 2005 levels.
In this work, the mitigation potential of i) technology and improved operations; ii) biofuels, and iii) the extension of current regional market-based measures to 2050 are quantified for low, central and high traffic growth projections.
Of the three types of measures studied, extension of current regional market-based measures (emissions trading) offers the greatest mitigation potential. None of the measures, or their combinations, for any growth scenario managed to meet ICAO’s aspirational 2020 carbon-neutral goal by 2050, the 2005 stabilization of emissions goal, or the 2005-10% stabilization of emissions goal. The 2% goal would only just be met by 2050, through assuming maximum reductions from technology, operations, and “speculative” availability of biofuels.
If a global emissions trading scheme were to be constructed that covered all international aviation, the emissions savings could be even larger than all other measures calculated in this study.