What is the relative humidity of the air?

Air humidity is a characteristic that reflects the degree of water vapor in the air.

Due to constant evaporation from the surface of rivers, seas, oceans, our atmosphere is saturated with water vapor.

For the quantitative assessment of humidity, the concepts of “absolute” humidity and “relative” humidity are used.

Absolute humidity ρ determines how much water vapor is contained in 1 m3 of air under current conditions. In other words, it is the density of water vapor, measured in g / m3.

Relative air humidity ϕ shows how far the steam is from saturation and is defined as the ratio of absolute humidity to the density of saturated steam at the same temperature:

ϕ = (ρ / ρ n.p.) * 100%.

The density of saturated steam is determined from the table.