Difference Between Humidity and Relative Humidity

Humidity vs Relative Humidity

The Earth’s atmosphere is composed of gases which are held together by gravity. It protects the Earth and all living things therein from solar radiation. It consists of different layers with pressure, thickness, density, and mass that also varies. Changes in the atmosphere can produce variations in the conditions of the atmosphere which can greatly affect the Earth and its inhabitants. One of the factors which can cause these changes in the air is humidity.

Humidity refers to the amount of water vapor in the air or atmosphere. It is characterized not by moist air but by the water content of the mixture of water vapor and other components of the air. Water vapor increases in the atmosphere through evaporation. Water from lakes, rivers, oceans, and other ground sources evaporates into the air where it is transported to different places. It is the moisture in the air which combines with its other constituents.

Humidity indicates the probability of fog which is caused by water vapor suspended near the ground; precipitation, which is caused by water vapor falling down as rain, snow, hail, or sleet; and dew, which is caused by overnight condensation of water vapor on a cool surface.

Humidity may be absolute or relative. Absolute humidity is the amount of water vapor in a unit volume of air which is expressed in kilograms per cubic meter. It does not change according to the temperature of the air. When there is a high amount of water vapor in the air, absolute humidity will also be high.

Relative humidity is the percentage or ratio of the amount of water vapor in a volume of air at a given temperature and the amount that it can hold at that given temperature. An amount of water vapor in warm air will result to a lower relative humidity than in cool air.

When the relative humidity is high, the evaporation of the moisture of the skin is reduced and decreases the effectiveness of sweating in cooling the body. The heat index which is used during the summer is used to measure this effect. It is not only influenced by temperature but also by the air’s moisture content or absolute humidity and the saturated vapor pressure. It is used in circumstances wherein the rate of water evaporation is necessary.

Summary:

1.Humidity is the amount of water vapor in the atmosphere while relative humidity is one type of humidity.
2.Humidity is the water content of the mixture of water vapor and other elements found in the air while relative humidity is the percentage of water vapor in the air at a given temperature.
3.Humidity is used to determine the likelihood of precipitation, fog, or dew while relative humidity is used for climate control and how it affects the health, comfort, and safety of humans.
4.Relative humidity is also used to ensure the safety of machines, vehicles, and buildings while determining the humidity of a certain place provides a way to gauge the weather.