Fig. 1: Scenarios representing the future of commercial aviation in Europe.
a Illustration of the system modelled, comprising lifecycle of the aircraft fleet and the lifecycle of the fuels (lower boxes connected by solid arrows). Key scenario parameters (upper boxes) influence the system (dashed arrows), e.g., the fuel supply adapts to the demands of the aircraft fleet, but also to the prescribed share of alternative aviation fuels (AAF) (see also Supplementary Figs. 1–3). Scenario parameter values are shown with the corresponding colours and line styles used to distinguish scenarios in later figures. b The volume of air traffic in revenue passenger-kilometres (RPK) per year according to four trajectories: high growth (blue line), base growth (grey line, not included in the scenarios presented in the main text), and low growth (orange line), which are based on EUROCONTROL50,51, and degrowth (red line). c The share of AAF in the aviation fuel supply per year as modelled based on ReFuelEU18 (dashed grey line, not included in the scenarios presented in the main text) and how we extend ReFuelEU beyond 2050 (solid black line).
