Aviation contrails, long-recognised but often overlooked contributors to climate change, are gaining significant attention in both scientific and policy circles. A recent open letter signed by a prominent coalition of aviation and climate scientists has called for urgent action to address the warming effects of contrails, marking a pivotal moment in the broader discussion on aviation’s environmental impact.

The open letter, addressed to global decision-makers, highlights the critical role of contrails in exacerbating climate change. Signed by esteemed figures such as Professor Christian Brand, Emeritus Professor of Transport, Energy and Climate Change at the University of Oxford, and Dr Philippe Quirion, Director of Research at France’s CNRS, the letter underscores the necessity of tackling aviation’s non-CO2 effects, with a particular focus on contrails.