What Is Humidity And Relative Humidity?
When the air contains large quantities of moisture, humidity is said to be high. Humidity depends on the moisture of the air at any given temperature there is a limit to the amount of moisture that the air can hold. When this limit is reached, the air is said to be saturated or at dew- point. Cold air can hold only relatively small quantities of water vapour before becoming saturated. However this amount increases rapidly as the temperature rises. At normal atmospheric pressure at sea level. An increase in temperature of about 10 Celsius doubles the air’s moisture capacity. For example saturated at 18 Celsius contains twice as much moisture as saturated air at 7 Celsius. Therefore the amount of precipitation obtained from warm air is generally greater than that from cold air. The normal term used to express the amount of moisture in weather studies is relative humidity. This refers to the amount of water vapour in the air at a given temperature. If the RH is 100% then the air is satura