Troposphere thickness and equatorial convection — UPSC Prelims PYQ 2024
Consider the following statements:
- Statement-I: The thickness of the troposphere at the equator is much greater as compared to the poles.
- Statement-II: At the equator, heat is transported to great heights by strong convectional currents.
Which one of the following is correct in respect of the above statements?
- Both Statement-I and Statement-II are correct and Statement-II explains Statement-I
- Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
- Statement-I is correct, but Statement-II is incorrect
- Statement-I is incorrect, but Statement-II is correct
Explanation
Statement 1 is correct
- The troposphere is thicker at the equator (16-18 km) than at the poles (about 8 km). The tropopause marks the upper boundary of the troposphere, separating it from the stratosphere.
Statement 2 is correct and is the correct explanation for statement 1
- At the equator, intense solar heating causes strong convectional currents, which carry heat and air upward to higher altitudes. Less intense solar radiation at the poles results in weaker convection and a thinner troposphere. These strong convectional currents at the equator are the primary reason for the greater thickness of the troposphere there; hence, Statement-II explains Statement-I.
Answer: (a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I; Difficulty Level: Easy
