The wide range of possible aviation demand futures after the COVID-19 pandemic

Aviation has been identified as one of the crucial hard-to-abate sectors, as long-range aviation in particular will continue to depend on liquid fuels for the foreseeable future. The sector was also one of the fastest growing emitters of fossil CO2 emissions until 2019 but experienced sharply reduced demand during the COVID-19 pandemic, making future demand outlooks more uncertain. While past studies have looked at the variation in future aviation demands due to variations in demographics, income levels, and pricing policies, an exploration of potentially more sustainable demand futures does not yet exist. Here we use an open-source model with a detailed representation of country-level aviation demand per international/domestic and business/leisure segments to analyze a range of scenarios based on a consistent and comprehensive interpretation of the qualitative narratives related to behavioural aspects as well as the socioeconomic data from different shared socioeconomic pathways (SSPs). Our results show a potential stabilization of global aviation demand at roughly twice the 2019 level in an SSP1 scenario, a weakened growth for an SSP2 scenario, while an SSP5 scenario projects an aviation future virtually unaffected by the COVID-19 shock, resulting in continued high growth rates. Further results show that without specific interventions that change the past demand growth patterns, the aviation sector could grow to levels that are very challenging to defossilize in a sustainable manner. Therefore, policies aiming at less frequent flying seem to be an important component of long-term decarbonisation strategies, and decisions regarding airport extensions should carefully assess the risk of stranded infrastructure.