4.3.1. Significance of Relative Humidity

The absolute humidity determines the amount of precipitation while the relative humidity tells us about the possibility of precipitation. The high and low relative humidity indicates the possibility of wet and dry conditions respectively. Evaporation decreases when there is high relative humidity and vice versa. Relative humidity is directly related to human health. That is why, the equatorial region with high temperature and high relative humidity, and the tropical hot deserts with very low relative humidity are unfavourable for human health.

Absolute Humidity	Relative Humidity
It helps us to know the actual amount of water vapour present in air.	It shows the ratio of water vapour actually present in the air at a given temperature to the retentive capacity of humidity of the same parcel of air at the same temperature.
It does not take temperature into account.	It takes temperature into account.
It is expressed in grams per cubic metre.	It is expressed in percentages.
It Is not a useful measure of humidity because it does not tell us the amount of water vapour required for the air to become saturated.	It is a useful measure of humidity because it can show how far the air is humid.