A new study, a collaboration between INRAE, ENAC, ISAE-SUPAERO, and ADEME, analyzes the major transition plans for global civil aviation by 2050. Scientists conclude that despite ongoing efforts, current greenhouse gas emission reduction strategies are insufficient to achieve sustainability. The findings, published in Nature Communications, call for a reassessment of supply and demand policies in the sector.
In the context of climate change, numerous organizations have developed roadmaps to move towards carbon neutrality in aviation. These plans rely on levers such as alternative fuels and improved aircraft efficiency. However, the research team, including experts in bioeconomy, environment, and aeronautics, evaluated these strategies against the planetary boundaries, a novel approach for this type of analysis. The study quantifies the environmental impacts and resource needs by 2050, considering various scenarios for air traffic evolution.
The scientific method employed is based on the concept of an environmental budget, similar to a carbon budget. It defines maximum consumption thresholds for various human activities to respect planetary boundaries. For aviation, principles of economic sharing (based on global GDP) and ethical sharing (based on relative impact) were applied. Life cycle assessment of fuels allowed for the evaluation of resource needs like freshwater and energy, as well as agricultural land use and carbon capture capacities. The study also traces the share of historical climate budget consumed by the sector.
The results indicate that while aviation meets some planetary budgets, none of the studied decarbonization plans allow for simultaneous compliance with all of them. Budgets related to climate and biosphere integrity are systematically exceeded. Furthermore, the most ambitious strategies involve significant resource costs. The authors therefore advocate for maintaining current technological measures while implementing policies to manage air traffic demand for a true environmental sustainability trajectory.
