Andreas von Mallinckrodt/Shutterstock Save for later Print Download Share Recommendations in a new study on the science and climate effects of aircraft contrails released on May 8 may never be implemented in the US after the Trump administration’s budget cuts eviscerated the National Academies of Science, Engineering and Medicine. In early 2024, NASA requested the NAS conduct a study on the impact of contrails — non-CO2 emissions that can have as great a climate change effect as CO2. The committee set up to undertake the study gathered data and consulted with airlines, aircraft manufacturers, atmospheric scientists and propulsion engineers.