Consider the following statements:

1. Assertion (A): The thickness of the atmosphere is maximum over the Equator.
2. Reason (R): High insolation and strong convection currents occur over the Equator.

Options:

1. Both A and R are individually true and R is the correct explanation of A
2. Both A and R are individually true but R is not the correct explanation of A
3. A is true but R is false
4. A is false but R is true

Explanation

Option (a) is correct

• Both Assertion and Reason are true, and Reason correctly explains the Assertion. The troposphere is thickest at the equator (~18 km) and thinnest at the poles (~8 km). This greater thickness results from intense solar heating in the tropics, which drives strong convectional currents that lift heat and moisture to higher altitudes, raising the tropopause. The ITCZ illustrates this process, in which maximum insolation produces deep convection and elevates the tropopause over the equator.

Answer: (a) Both A and R are individually true and R is the correct explanation of A