JFDee
Senior Member.
The DLR has chimed in with recent research about contrail coverage during the low-air-travel period.
https://www.dlr.de/content/en/artic...sation-trails-due-to-reduced-air-traffic.html
https://www.dlr.de/content/en/artic...sation-trails-due-to-reduced-air-traffic.html