> But contrails are just the tiniest > tiniest fraction of the sky somewhere Initially yes, but as a contrail diffuses it acts like a seed for wider cirrus clo

> But contrails are just the tiniest > tiniest fraction of the sky somewhere Initially yes, but as a contrail diffuses it acts like a seed for wider cirrus cloud formation. During COVID lockdown, researchers at Universität Leipzig found that the reduction of air travel correspondingly reduced cirrus formation by 9% in the area studied.