Question

The figure shows a schematic of vertical profiles of concentrations of two gases P and Q in the atmosphere near a coastal station. The correct pair representing P and Q, respectively, is

• A. Water vapor and CO$_2$
• B. O$_3$ and water vapor
• C. CO$_2$ and O$_3$
• D. N$_2$ and O$_2$

Hint:

Water vapor is concentrated near the surface, while gases like CO$_2$ have a more even distribution in the upper atmosphere.

Answer 1

The Correct Option is A

The vertical concentration profile for gas P shows a sharp decrease in concentration with increasing height, which is characteristic of water vapor. Water vapor is highly concentrated near the Earth's surface and its concentration decreases rapidly with height.
The vertical profile for gas Q shows a sharp increase in concentration at higher altitudes, indicating that the gas is more concentrated at higher altitudes, which is a characteristic of CO$_2$. CO$_2$ concentration increases with altitude in the atmosphere due to the absorption of solar radiation and various atmospheric processes.
Thus, the correct pair is:
\[ \boxed{\text{(A) Water vapor and CO$_2$}}. \]