Why is desert sand hot during the day and cold at night?

The primary reason for the significant temperature difference between daytime and nighttime in desert environments lies in the unique characteristics of sand and the surrounding atmosphere. During the day, desert sand becomes extremely hot due to its ability to absorb and store heat from the sun. Sand has low thermal conductivity, which means it does not transfer heat efficiently. As a result, the heat from the sun gets trapped within the sand particles, leading to high surface temperatures.

On the other hand, deserts are characterized by clear skies with little cloud cover. This allows for efficient heat loss through radiation at night. As the sun sets, the sand rapidly loses its heat back into the atmosphere through infrared radiation. Since there is minimal atmospheric moisture or cloud cover to trap the heat, the temperature drops drastically. The absence of vegetation and other heat-absorbing objects in deserts further contributes to the rapid heat loss.

This diurnal temperature variation in deserts can be substantial. During the day, desert sand temperatures can reach as high as 60°C (140°F) or even higher, while at night, they can drop to freezing temperatures or below, sometimes reaching as low as -18°C (0°F). This significant temperature fluctuation is a distinctive feature of desert environments.