Cloudy nights are warmer compared to clear cloudless nights, because clouds
- Aprevent cold waves from the sky from descending on Earth
- Breflect back heat given off by EarthCorrect
- Cproduce heat and radiate it towards Earth
- Dabsorb heat from the atmosphere and send it towards Earth
Explanation
The correct answer is B because of the process of terrestrial radiation. During the day, the Earth absorbs solar energy. At night, the Earth releases this energy back into space as infrared radiation or long-wave heat. On a clear night, this heat escapes easily into the upper atmosphere, cooling the surface. However, on a cloudy night, the clouds act like a blanket. They trap the outgoing terrestrial radiation and reflect it back toward the Earths surface, preventing it from escaping. This results in warmer temperatures compared to clear nights where the heat is lost to space.

Related questions
More UPSC Prelims practice from the same subject and topic.
- Prelims 2001GS1geography
The temperature and rainfall of a meteorological station are given below: J F M A M J J A S O N D Temperature (°C) 9.4 10.6 11.7 12.2 13.3 13.9 13.9 14.4 15.6 15.0 13.3 10.6 Rainfall (cm) 12.2 9.1 7.9…
- Prelims 2001GS1geography
Match List I with List II and select the correct answer using the codes given below the Lists: List I (Local Wind) (Region) I. Fohn A) Argentina II. Samun B) Kurdistan III. Santa Ana C) California IV.…
- Prelims 2001GS1geography
Assertion (A): Anti-cyclonic conditions are formed in winter season when atmospheric pressure is high and air temperatures are low. Reason (R): Winter rainfall in Northern India causes development of …
- Prelims 2001GS1geography
Assertion (A): During the Neap Tides, the high tide is lower and the low tide is higher than usual. Reason (R): The Neap Tide, unlike the Spring Tide, occurs on the New Moon instead of on the Full Moo…
- Prelims 2001GS1geography
In the shaded area of the above map, the mean temperature for the month of July varies between
- Prelims 2001GS1geography
Assertion (A): The boiling point of water decreases as the altitude increases. Reason (R): The atmospheric pressure increases with altitude.