It explains that boiling point is the temperature at which a liquid's vapor pressure equals atmospheric pressure, and demonstrates how changes in pressure affect the boiling point of water through ...

An increased exposure to dry air — occurring more due to global warming — could heighten risk of dehydration and inflammation ...

so as water vapor increases, the density of air decreases. Temperature also changes the density of air. As air gets warmer it expands and becomes less dense, causing atmospheric pressure to fall.