Impact of Non-CO2 Pricing on Routing and Ticket Fares in Aviation: Strategies to Address Uncertainties in Climate Policies

Kurzfassung

CO2 emissions accounts for only one-third of the current climate effect of air traffic, with the majority arising from non-CO2 effects like contrail-induced cloudiness and nitrogen oxides. In response, the EU revised its Emissions Trading System, requiring Member States to ensure that aircraft operators monitor and report total climate effects and provide CO2 equivalent (CO2e) emissions per flight since January 2025. By December 2027, the EU might propose further legislation introducing non-CO2 pricing to incentivize mitigation. Following the ’Polluter-Pays Principle’, CO2e pricing will affect operators, influencing ticket prices and encouraging climate-optimized routings. This study examines how key policy design choices, like CO2e accounting methods, carbon price levels, and climate metrics, affect routing, mitigation potential, and ticket prices. Initial results for selected routes and weather situations show operational mitigation potentials depend strongly on weather, while ticket price increases are mainly driven by the accounted share of CO2e and carbon price. Gradual CO2e accounting could moderate passenger costs. Our estimates show ticket price increases averaging 1.1% to 5.6%, with CO2e abatement costs between 3-74C per 23 tonne (median 14C). Estimated costs are lower than in other sectors like wind, solar, or direct air capture, especially on days with effective contrail avoidance. Incorporating cooling contrails into pricing could reduce costs through compensation but remains controversial. Strategies to mitigate policy risks are essential given large uncertainties in non-CO2 modeling that affect data accuracy in monitoring frameworks and could incentivize harmful re-routing under CO2e pricing. These include using ensemble weather forecasts and implementing uncertainty-based CO2e accounting.