The climate impact of contrails – why targeting a small share of flights could make a big difference

Magazine article, 2026

The climate impact of persistent contrails from aircraft is receiving growing attention from policymakers, with the EU currently developing policies to integrate them into climate regulations. In a recent study, researchers from Chalmers University of Technology and Göteborg University in Sweden, together with Imperial College, developed methods and tools to study the climate impact of persistent contrails compared to carbon dioxide emissions from aviation. They studied their impact from nearly half a million flights across the North Atlantic and from global aviation as a whole, and analysed the potential climate benefits of rerouting flights as a strategy to avoid contrail formation. In this article, Christian Azar and Daniel Johansson summarise key insights from the study.