Climate change, where do we come from and where are we going? European aviation sector behaviour.

Climate change has caused great pressure on the air transport sector. European airlines are subject to a pioneering CO 2 emissions regime. This paper sets out, first, to ascertain whether the European aviation sector has adapted since the launch of the European Union (EU) Emissions Trading Scheme (ETS). Second, based on the answer to the above, we predict the situation of the sector in the medium and long term. The study sample was formed by the top 10 European airlines. The years covered are those since the inclusion of the airline sector in the emissions regime (2012–2019). Clusters were defined by eco-efficiency level using K -means cluster analysis and the Markov model was applied to predict future behaviour. The results have shown, on the one hand, that the larger airlines were the most eco-efficient throughout the study period. On the other hand, companies focused on a low-cost strategy have behaved worse since, although they have also experienced significant improvements in their use of air traffic capacity, even above the large airlines, they have not evolved to a higher level of CO 2 emission efficiency and even getting worse in some cases. However, in the medium and long term, our estimate for the sector is a trend towards minimal eco-efficiency in CO 2 emissions. As governments continue to increase emission limitation requirements, in order not to jeopardise the sustainability of the aviation sector, it is advisable to encourage investments in the development of biofuels and their supply chain, international agreements to optimise flight routes or projects to improve the energy efficiency of new engines. • Eco-efficiency for European airlines in the framework of the EU ETS was analysed. • Larger airlines were found to be more eco-efficient than low-cost airlines. • Medium and long term, a trend towards lower eco-efficiency has been estimated. • More government support is recommended to clearly drive the zero emission strategy. • Greater coherence and coordination between international legal regimes is needed. [ABSTRACT FROM AUTHOR]