Deserts have low humidity, which means that they do not retain heat very well. During the day, the sun heats up the surface of the desert quickly, but as soon as the sun sets, the heat rapidly escapes into the atmosphere due to the lack of humidity and cloud cover. This causes the temperature to drop dramatically, leading to extreme temperature variations between day and night. Additionally, deserts are often located in areas with high atmospheric pressure, which further enhances the temperature difference between day and night.
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