Question

In which of the following layers of atmosphere, does the temperature decrease with the increase in height from the earth's surface?
(A). Troposphere
(B). Mesosphere
(C). Thermosphere
(D). Stratosphere
Choose the correct answer from the options given below:

• A. (A), (B) and (D) only.
• B. (A) and (B) only.
• C. (A) and (D) only
• D. (B), (C) and (D) only.

Hint:

Remember the temperature trend in the atmospheric layers from the ground up: \textbf{Decreases (T), Increases (S), Decreases (M), Increases (T)}. The layers are \textbf{T}roposphere, \textbf{S}tratosphere, \textbf{M}esosphere, \textbf{T}hermosphere.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The question asks to identify the layers of the Earth's atmosphere where the temperature profile shows a decrease in temperature with an increase in altitude. This is known as a negative lapse rate.
Step 2: Detailed Explanation:
Let's examine the temperature profile of each layer, starting from the ground up:
- (A) Troposphere (0-12 km): This is the lowest layer where we live and where most weather occurs. The temperature decreases with altitude because the air is heated from the ground up by terrestrial radiation.
- (D) Stratosphere (12-50 km): Temperature increases with altitude in this layer. This is due to the absorption of ultraviolet (UV) radiation by the ozone layer.
- (B) Mesosphere (50-80 km): Above the stratosphere, the temperature once again decreases with altitude. This is the coldest layer of the atmosphere.
- (C) Thermosphere (80+ km): Temperature increases dramatically with altitude due to the absorption of high-energy solar radiation by the sparse gas molecules.
Step 3: Final Answer:
Temperature decreases with increasing height in the Troposphere (A) and the Mesosphere (B). Therefore, the correct option is (A) and (B) only.