Why is it important to know about humidity?
Humidity is an important thing to understand as it immensely affects the weather, climate, and entire global climate change. It also affects the indoor environments. Hence it is imperative to understand its concept as it could help you decide where to keep your food essentials, books or other things that could get affected by humidity.
What is Humidity?
Humidity is the amount of water vapour in the air, and a proportion of that water condenses in a constant cycle. When the water evaporates, it rises and disperses into the surrounding air as the gaseous water vapour. Humidity can make hot temperatures unbearable than they already are.
The more the water evaporates in an area, the higher the humidity of that area will be. Therefore, you might have observed that the coastal areas are much more humid than other areas.
Absolute humidity vs Relative humidity vs Dew Point
a) Absolute humidity
Absolute humidity can be defined as the grams of moisture per cubic meter of air (g/m3). It can be calculated by dividing the mass of water vapour with the mass of dry air at a given temperature. The hotter the temperature is, the more the water evaporates and more will be the absolute humidity.
b) Relative humidity
The relative humidity is the amount of water vapour in the air relative to what air can hold. It can also be said that it is the ratio of the current absolute humidity to the highest possible absolute humidity.
c) Dew Point
The maximum amount of water vapour is possible when the air becomes saturated. The saturation of air is entirely dependent on temperature. Dew point is the air temperature, which is indispensable for the water to condense and evaporate at the same rate.
When the air temperature happens to be lower than the dew point, condensation occurs. If the temperature is higher, it does not allow condensation to occur; instead, it only allows water to evaporate swiftly.
How do we measure Humidity?
A device named a hygrometer or psychrometer enables to measure the humidity. The basic hygrometer consists of 2 thermometers mounted together with a handle attached to a chain. One thermometer is ordinary, while the other one is equipped with a clock wick over its bulb, also known as the wet-bulb thermometer.
How does a psychrometer help to measure relative humidity?
A psychrometer is attached with two thermometers and also known as a sling psychrometer. The dry thermometer helps to measure the actual air temperature; the other thermometer (wet-bulb thermometer) consists of a wet cloth at its tip. The thermometer lower its reading as the water molecule starts evaporating from the wet bulb’s surface.
The amount of water vapour in the air is entirely dependent on the rate of evaporation. If the relative humidity is measured at 100%, no water will be evaporated from the wet bulb, and the readings on both the thermometers will be the same. The top is a wet bulb, while the bottom one is a dry bulb thermometer.
Does humidity have any effects on the body?
It might become unbearable for you and especially your skin if the dew point becomes higher. As your skin might be affected by intense heat, allowing it not to cool as efficiently as when the dew point is lower. This could make your skin lose a considerable amount of moisture. Moreover, the heat is also removed from your body, required to change the water from its liquid state to a vapour state.
The loss of moisture is directly proportional to the amount of water vaporised in the air. It is one reason why desert regions feel colder to you even with a temperature of 20 degrees F. As in desert areas, your skin tends to lose water at a faster rate, causing your body not to feel the warming effect of higher air temperature.