What Do You Know About Humidity?

Moisture gathers on the outside of the pitcher, containing ice water. We know the air is the origin of this moisture. The presence of moisture in the air is a permanent feature and it is in the form of water vapour. On the outside surface of the pitcher which is ice cold the vapour in the air gets condensed on coming in contact with it. We can see this for its presence. Humidity is a simple word that means the presence of water vapour in the air. It is found everywhere in every season, even in the deserts. Yes, the extent does vary on certain conditions.

We express humidity in two ways. One is ‘absolute humidity and the other is ‘relative humidity. The water vapour in each unit volume of air is the quantity that expresses ‘Absolute humidity’. This per unit quantity does not help us much for most practical purposes. The mere expression of so much quantity of moisture does not tell us whether the air will fell dry or humid. The more easily moisture can evaporate into the air from our body, the more comfortable we feel. The evaporative power is dependent on temperature and absolute humidity is silent about this indication.

The relative humidity is expressed as a percentage. “One hundred per cent” stands for air that is saturated or completely filled with water content. The higher temperature can hold a greater quantity of water vapour in the air. Thus 90 per cent relative humidity on a hot day means an awful lot of moisture in the air and the day will be uncomfortable.