Question

Which of the following are the reasons for hot deserts being cold at night?

• A. Absence of moisture in the atmosphere.
• B. High humidity in deserts
• C. Cooling down of sand particles
• D. Absence of fauna

Answer 1

Answer: (A), (C)

The correct options are
A Absence of moisture in the atmosphere.
C Cooling down of sand particles

The temperature in deserts may reach upto 50 degree celsius during day time and it falls drastically in the night.
This happens due to absence of moisture in the atmosphere. Sand particles heat up and cool down at a faster rate. At night, when there is no Sun, the sand starts losing heat and since the number of water molecules present in the atmosphere (Humidity) is also very low, the reflected heat from the sand particles also escapes, cooling it down further.