UPSC CSE Prelims
Question 74
Consider the following statements :
- High clouds primarily reflect solar radiation and cool the surface of the Earth.
- Low clouds have a high absorption of infrared radiation emanating from the Earth's surface and thus cause warming effect.
Which of the statements given above is/are correct ?
View correct answer and explanation
Correct answer: D
Correct Option: D (Neither 1 nor 2)
Explanation: High thin clouds tend to warm Earth by retaining longwave radiation; low thick clouds often cool it by reflecting incoming sunlight.
Statement / Pair / Item-wise Analysis:
1. False / does not qualify - High cirrus clouds commonly trap terrestrial infrared radiation and have a net warming effect rather than primarily cooling.
2. False / does not qualify - Although low clouds absorb infrared, their strong reflection of solar light typically dominates, producing net cooling.
Option-wise Analysis:
A. Incorrect-includes 1 even though High cirrus clouds commonly trap terrestrial infrared radiation and have a net warming effect rather than primarily cooling.
B. Incorrect-includes 2 even though Although low clouds absorb infrared, their strong reflection of solar light typically dominates, producing net cooling.
C. Incorrect-includes 1 even though High cirrus clouds commonly trap terrestrial infrared radiation and have a net warming effect rather than primarily cooling.; includes 2 even though Although low clouds absorb infrared, their strong reflection of solar light typically dominates, producing net cooling.
D. Correct-selects exactly the correct statements/items identified above.