June 3, 2021 | Documents

New assessments of the real climate impact of Swiss aviation by the Swiss Academy of Natural Sciences show that it is 50% higher than in earlier estimates. As a consequence, air travel is now recognized as the most important driver of anthropogenic climate change among all Swiss economic sectors, ahead of ground transport. Furthermore, it is widely expected that air travel demand in Switzerland will return to pre-COVID levels and continue its rise thereafter. We estimate that the air ticket tax of the revised CO2 Act would significantly reduce air travel demand in the future, by encouraging substitution behaviour away from air travel. The law would thus rapidly reduce the climate impact of air transport.


This new E4S white paper reviews the most important options to reduce the climate impact of air travel and the instruments considered or implemented elsewhere in the world to encourage such a development. It analyses the air ticket tax of the revised CO2 Act in depth. It shows that, with the tax schedule proposed by the Federal Council, air travel would be reduced by 21% relative to its level in the absence of the tax, while revenues of almost one billion francs would be generated. The decrease in the climate impact of Swiss aviation would be somewhat smaller, about 16%, due to the relatively low upper limit on the air ticket tax of 120 CHF, which applies to the particularly polluting intercontinental flights in Business and First class. On average, such trips are 15 times more polluting than intra-European flights in Economy, which are taxed at 30 CHF, and up to 17 times more when they include a stopover. Even the tax rate for intercontinental flights in Economy (90 CHF) does not reflect the fact that these flights are on average 5 to 6 times more polluting than intra-European flights in the same class. Hence, as a future improvement of the air ticket tax, the white paper recommends increasing the tax rates for long-haul flights.

Philippe Thalmann, EPFL

Fleance Cocker, EPFL

Pallivathukkal Cherian Abraham, IMD

Marius Brülhart, UNIL-HEC

Nikolai Orgland, EPFL

Dominic Rohner, UNIL-HEC

Michael Yaziji, IMD