When someone says, “It’s humid outside,” they are generally referring to relative humidity, but did you know that there are other “types” of humidity? So what is absolute humidity and specific humidity? All humidity readings measure the water vapor content in the air. Understanding the difference between different measurements of humidity will help prevent you from misinterpreting the information you’re given. Here, learn just what this weather terminology means and the difference between absolute, relative, and specific humidity.
What is Absolute Humidity?
Absolute humidity is the amount of water vapor divided by the total air and water vapor mixture. Determining absolute humidity this way is defined as volumetric humidity. It can range from 0 to about 30 grams per cubic meter when the air reading 86 degrees F (30 degrees C) is completely saturated.
Absolute humidity is altered when air pressure changes. This is because varying air pressure changes air’s density. Because of this, chemical engineers often calculate absolute humidity by taking a mass of water vapor divided by a mass of dry air. This is known as the mass mixing ratio.
What is the Difference between Absolute and Relative Humidity?
Units: Absolute humidity is usually written in g/kg or kg/kg. Relative humidity is written as a percentage (%).
Purpose: Absolute humidity is used for engineering calculations. Relative humidity is important for weather forecasts and reports, indicating the likelihood of precipitation, fog, or morning dew.
What is the Difference between Absolute and Specific Humidity?
Calculation: Absolute humidity is the amount of water vapor divided by the total air and water vapor mixture. Specific humidity is the total amount of water vapor divided by the amount of dry air in a particular mass. Otherwise, absolute and specific humidity are quite similar in concept.
Now that you know what absolute humidity is, visit our website to learn more about other weather terminology and facts.
Information Provided By: WeatherCaster App Staff