Correct Option
The correct option is 1 and 3 only.
Explanation
The atmosphere is divided into five distinct layers based on temperature changes. The stratosphere is the second layer, situated immediately above the troposphere and separated from it by the tropopause.
Statement-wise Analysis
- Statement 1 is Correct: The stratosphere extends from the tropopause up to a height of approximately 50 km above the Earth's surface. At the top of this layer lies the stratopause.
- Statement 2 is Incorrect: The stratosphere is not devoid of ozone. In fact, it contains the ozone layer (ozonosphere), which absorbs harmful ultraviolet (UV) radiation from the sun. While ground-level ozone exists in the troposphere as a pollutant, the primary concentration of protective ozone is found in the stratosphere.
- Statement 3 is Correct: This layer is almost entirely free from clouds and associated weather phenomena, such as storms and rainfall, which are characteristic of the troposphere. The absence of turbulence and weather disturbances makes the lower stratosphere the most ideal layer for flying jet aircraft.
Key Takeaway: The stratosphere extends up to 50 km, contains the vital ozone layer that absorbs UV radiation, and is characterized by stable atmospheric conditions suitable for aviation.