For instance, nitrogen oxides emitted in aircraft exhaust increase the production of ozone, a major greenhouse gas, but they also destroy methane, a big contributor to atmospheric warming. Also contrails heat and cool the planet at the same time by trapping atmospheric heat while reflecting sunlight. The net result is that contrails are only about half as bad as previously thought. The scientists say that despite the findings, aviation still needs to clean up its act and the COVID-created hiatus in aviation activity isn’t going to help much. “It’s not going to make much difference in the long term,” said researcher David Lee at Manchester Metropolitan University in the U.K.
This is a companion discussion topic for the original entry at https://www.avweb.com/aviation-news/aviation-a-smaller-contributor-to-climate-change-than-previously-thought