If the NFL really cared so much about consistent inflation, they would use nitrogen to inflate the balls. Nitrogen is much less susceptible to changing pressure when temps change. The pressure would remain stable at room temp as at 32F.
It's not so much the nitrogen as such, but the water vapor contained in regular air that makes the difference! It's "dry" gas you want.
If the NFL really cared so much about consistent inflation, they would use nitrogen to inflate the balls. Nitrogen is much less susceptible to changing pressure when temps change. The pressure would remain stable at room temp as at 32F.
Trolling? Because that’s not even a little bit true.
If they cared about consistent inflation, they’d measure the balls on the field before the game. CO2, N2, and O2 do not notably differ from each other in their pressure response to temperature. Their difference from Helium, which is closest to an ‘ideal gas’, is far smaller than is relevant to this issue.
Here’s the equation as initially worked out with air, and then later confirmed as the specific gas not mattering:
P1*T2/T1 = P2, where temperature and pressure use an absolute scale. That’s it. Add 14.7 PSI to gauge pressure, and 460 to F to convert into the needed units.
So the natural variation in pressure of footballs in NFL games from temperature alone is nearly 6 PSI.
The footballs being wet has an additional effect which fully explains the variation amongst the footballs in the game (with or without realizing that 12-2 is not 11).
This whole thing was silly.