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Air can hold water in proportion to partial pressure of water vapor. This is affected by temperature. But is the water capacity of air also affected by ambient pressure?

I did find some answers that water holding capacity of air decreases with increasing pressure. Quora link, UCAR link

But I was unable to find any equations that would tell me exactly how much it changes.

In this case we talk only about change in pressure. So temperature and volume would stay the same.

I will be glad for any sources that can answer me this relationship.

Foxtrot
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From most of what I've read on the topic I'd infer that the dew-point is only dependent on two things:

  • temperature
  • partial water vapor pressure

Adding dry air containing absolutely no water vapor at the same temperature into the container would affect neither of the two, and therefore not change the dew-point = water carrying capacity of the air-mixture.

One thing that makes me unsure of this conclusion is the answer by user @Chemomechanics to this question: Why atmospheric pressure does not influence vapor pressure of water but only temperature does? where he states that there is a small change because pressure adds energy to the system, though I fail to follow his math sadly.

xogoxec344
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