Question

The boundary between the troposphere and stratosphere is known as the

• A. Tropopause
• B. Stratopause
• C. Mesopause
• D. Thermopause

Hint:

• Atmospheric layers from bottom to top: Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere.
• The suffix "-pause" generally denotes the boundary at the top of a layer.
• Troposphere $\rightarrow$ Tropopause (boundary)
• Stratosphere $\rightarrow$ Stratopause (boundary)
• Mesosphere $\rightarrow$ Mesopause (boundary)
• Thermosphere $\rightarrow$ Thermopause (boundary, also called Exobase)

Answer 1

The Correct Option is A

The Earth's atmosphere is divided into several distinct layers based on temperature profiles: Option (A) Troposphere: The lowest layer, extending from the Earth's surface up to an average altitude of about 7-20 km (variable with latitude and season). Weather phenomena occur here, and temperature generally decreases with altitude. Option (B) Tropopause: This is the boundary region between the troposphere and the stratosphere. It is characterized by a point where the temperature stops decreasing with altitude and begins to remain constant or increase. Option (C) Stratosphere: Above the tropopause, extending to about 50 km. The ozone layer is located here, and temperature generally increases with altitude due to the absorption of UV radiation by ozone. Option (D) Stratopause: The boundary between the stratosphere and the mesosphere. Temperature reaches a maximum here. Option (E) Mesosphere: Above the stratopause, extending to about 85 km. Temperature decreases with altitude in this layer. Option (F) Mesopause: The boundary between the mesosphere and the thermosphere. This is the coldest part of Earth's atmosphere. Option (G) Thermosphere: Above the mesopause, where temperature increases significantly with altitude due to absorption of solar radiation. Option (H) Thermopause (Exobase): The boundary at the top of the thermosphere, leading to the exosphere. Therefore, the boundary between the troposphere and the stratosphere is the tropopause. \[ \boxed{\text{Tropopause}} \]