It’s common knowledge that daytime highs in the desert can reach into the 120s but that the temperature drops significantly at night.
However, many people are confused about the causes of this phenomenon and the severity of the nighttime cold. That being said, there is a wide variety of desert environments around the globe.
Most climates fall into one of four categories: subtropical, cold winter, coastal, or polar desert. Some of these deserts have the typical warm days and cool nights, while others may be permanently chilly.
We shall try to limit ourselves to the more prevalent varieties for this post, and those do typically have warm days and cooler nights.
Temperatures can range from a high of 100 degrees Fahrenheit during the day to a low of 40 degrees Fahrenheit at night in such deserts. But why do deserts get cold at night?
Why Do Deserts Get Cold At Night?
Temperature and Relative Humidity. Humidity, in its simplest definition, is water vapor in the atmosphere.
Humid air contains more water droplets in it. Simply put, water is a significantly better heat storage medium than air. Because of this, the air in humid regions retains its warmth for longer than it would in drier regions.
The water in the air keeps the temperature stable, not the air itself.
Because deserts are so dry, their relative humidity — the amount of water vapor in the air — is extremely low.
The sun no longer heats the desert at night, and the daytime heat does not remain trapped.
Due to this, some deserts can see nighttime temperatures below 40 degrees Fahrenheit, which is coat weather.
It’s worth noting that humid air is significantly more challenging to heat. It takes a lot more effort.
For this reason, even though the same amount of solar energy falls in deserts and wet regions, the former heat up significantly faster.
However, nighttime temperatures in some deserts can reach freezing. When conditions are right, the air temperature drops in dry regions.
For instance, this can occur when no clouds are present, no breeze is blowing, or the air contains very little moisture.
Also Read: Effects of air pollution
However, a lack of moisture is not always the case; some dry regions experience very high humidity levels.
In other words, you shouldn’t anticipate cold weather if you take a journey into the desert.
Even if the temperature drops, you could have a mild and pleasant evening. Notable examples include the cities of Dubai and Kuwait.
Why are desert nights so cold?
During the day, the sand’s solar radiation superheats the air and causes temperatures to skyrocket.
At night, however, most of the sand’s heat quickly escapes into the air, and there is no sunlight to re-heat it, leaving the sand and its surroundings colder than before.
Also Read: Modern world wonders
The primary cause of night temperature drops in deserts may surprise you.
Sand is the reason for the cold nights in deserts. The sand’s inability to retain heat makes the entire desert extremely warm.
The sand functions as a sort of Sun mirror. It does not absorb any of the heat from the sun but instead “radiates” it into the air, which is why daytime temperatures are so high.
The surface of the sand retains heat. When night arrives, the sand loses all heat accumulated during the day, and temperatures drop dramatically. After sunset, there is neither heat to absorb nor retain on the surface.
On the other hand, there are regions of Earth where the sun never shines, yet the temperature rarely fluctuates by more than a few degrees.
Why is the desert the only place this occurs? This is primarily due to the dry air. Heat retention at night is aided by humidity. Due to the low relative humidity in desert environments, heat is lost overnight.