Another thought about air density.

When calculating air density from absolute pressure, we need to know if a pressure increase, for example, is due to a lower ratio of moisture/air in the air column, or more air molecules in the column due to colder/slower molecules remaining in the column longer before diffusing out. So abs. pressure is not enough to calculate air density. We need all three variable quantities- abs. pressure, RH, and temp. Maybe these references can help clarify for you; note that p refers to the observed absolute pressure:

https://ipfs.io/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/Density_of_air.html

https://www.gribble.org/cycling/air_density.html

https://www.bipm.org/utils/en/pdf/Density_of_moist_air.pdf