Humidity and Temperature

The capacity of a gas to hold water depends on its temperature. The higher the temperature, the more water vapor it can contain.

  • normal room temperature air typically holds about 1% of water vapor

  • hot-atmosphere has greater capacity to hold water vapor

When the air holds the maximum amount of water vapor at a particular temperature it is said to be saturated.

  • Relative humidity is strongly governed by temperature.

  • Interaction of water-vapor with materials is often in proportion to relative humidity.

  • Lowering the relative humidity of surrounding air increases evaporation and drying of materials.

  • For the same amount of air and water-vapor, relative humidity decreases with increase in temperature of the gas mixture.

e.g.:

Temperature (\(^\circ\)C) 15 20 25 30 35 40
Relative humidity (%) 100 71 50 36 27 19