Question

The region of atmosphere having the constant temperature is

• A. Troposphere
• B. Mesopause
• C. Stratosphere
• D. Ionosphere

Hint:

Think about which atmospheric layer has a nearly flat temperature profile before the ozone driven rise begins.

Answer 1

The Correct Option is C

This question is about how temperature changes with height in the four named parts of the atmosphere.

1. Troposphere: Temperature drops continuously as altitude increases, so it never stays constant.
2. Mesopause: This is a narrow transition point, not a thick layer, marking where the mesosphere ends; it is the coldest spot in the atmosphere rather than a zone of constant temperature.
3. Stratosphere: Its lower section holds a steady, near constant temperature before the ozone layer causes temperature to climb in the upper part. This steady lower band is the reason the stratosphere is linked with constant temperature.
4. Ionosphere: Temperature rises steeply here because charged particles absorb a lot of solar energy, so this layer is far from constant.

Since only the stratosphere carries a broad, near flat temperature stretch, it is the correct answer.

Let's summarize:

• Troposphere: temperature falls with height.
• Stratosphere: nearly constant temperature in its lower part.
• Ionosphere: temperature rises sharply.

So the stratosphere, option (3), is the region best known for constant temperature.