[detsaoT]

This is pretty consistent with how one would expect the atmosphere would recover after a GIANT HOLE WAS BLOWN IN IT BY A NUCLEAR FREAKING BOMB.

The US Government is 100% responsible for creating that hole. Glad to see it wasn't permanent.

Wiki has the rundown here. I have always suspected that Starfish Prime is to blame.

[TXnMA]

Starfish Prime (250 miles altitude) was well outside the atmosphere.