RH

One of the most used terms in meteorology and in meteorological reports is that of relative humidity. Although we hear it daily on television and radio, few of us know what this means.

The term relative humidity It comes to mean nothing more than the ability of the air to absorb more moisture.

Let's suppose that in a weather report you hear relative humidity: 40%. This means that, from the moisture possible that the air could have the conditions prevailing at that time (pressure and temperature), it only has 40%.

As you may have noticed, the air cannot receive an unlimited amount of humidity, therefore if one in a day of thick fog, where the relative humidity is 100%, if a person perspires, it is very difficult to evaporate perspiration, which means that the elimination of body heat is not so rapid, causing hot flashes and general discomfort.

When the relative humidity reaches 100% it reaches what is known as saturation point.

Like all materials, air also has a limit to absorb moisture. Imagine that you have spilled a glass of water on the table and you want to dry it with a cloth. Depending on what material the cloth is made of, it can absorb more moisture than another made of another material, but there comes a time when it can no longer collect more water and you must wring it out.

The same happens with the air, and when this point is reached, it no longer has the capacity to continue receiving moisture, and the steam it condenses, commonly causing phenomena such as dew, fog, fog or frost.

The difference between relative humidity and absolute humidity is that the first is a percentage measure, that is, as many percent of the water that the air can contain, it has; Instead, absolute humidity is a measure of the amount of water by weight that the air contains, and it is used to represent grams or kilograms.

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