The aviation sector is a top-ten global emitter whose emissions are expected to rise dramatically by mid-century. Under current scenarios, the aviation sector could emit 56 GtCO2 over the period 2016-2050, or one-quarter of the remaining carbon budget.1 It is critical that the global aviation sector contribute its fair share towards achieving a 1.5°C future. Aviation, therefore, needs to immediately start to reduce its in-sector emissions, then rapidly reduce its emissions and fully decarbonize toward the second half of this century. In addition to the sector’s CO2 emissions, aviation’s non-CO2 effects need to be addressed. Aviation emissions are 2.1% of the global share, but when non-CO2 effects are included, aviation contributes an estimated 4.9% to the global warming problem. Hence, the global aviation sector must have both zero CO2 emissions and zero non-CO2 effects on the climate by the end of the century.
National governments, subnational governments, the aviation industry, international institutions, the private sector, and civil society must do more to harness viable technological and policy solutions to sharply reduce the sector’s emissions by 2050 and fully decarbonize within the second half of the century. While current policy measures set by governments are a step forward to addressing aviation’s runaway emissions, they are woefully insufficient to achieve necessary levels of deep decarbonization within the sector.
While many stakeholders have a role to play in the aviation industry’s decarbonization, bold government action will, in the end, define whether the aviation sector is able to contribute its fair share to ensure a 1.5°C future. A methodical next step for governments—at the subnational, national, regional and international level—is to set long-term decarbonization pathways for aviation that are compatible with the Paris Agreement and a roadmap to adhere to these pathways. The elements of a roadmap for aviation’s decarbonization include:
- Deploying near-term technology solutions (efficiency and operational measures and alternative fuels with lower lifecycle emissions than fossil jet fuel);
- Addressing non-CO2 effects through mitigation measures;
- Investing in transformative, breakthrough clean aviation technologies;
- Strengthening the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA);
- Strengthening the ICAO CO2 standard;
- Revisiting aviation subsidies;
- Developing new mobility solutions to support modal shift;
- Creating new business models for the aviation industry;
- Climate-proofing aviation against the effects of a changing climate; and
- Ensuring compatibility with the Paris Agreement.