Question

Where is the ozone layer found?

Answer 1

Hint:
We can use the knowledge about the composition of different layers of atmosphere to know where different gases are found in our atmosphere.

Complete step by step solutions
We know that the position of our planet with respect to the Sun is favorable for life sustenance but yet there is harmful radiation coming from the Sun that needs to be blocked away but not all of it as we need heat energy as well. This selection and protection is the main role played by our atmosphere that surrounds our planet as a blanket.

Atmospheric composition, temperature, density and other properties vary with height and based on that we have divided our atmosphere into the following layers:

1. Troposphere: This layer of atmosphere extends upto $ \sim 10\;{\rm{km}}$ from the sea level that is taken to be as the reference point. This is where all of us live along with all other organisms. The air is breathable here and contains water vapor and clouds as well. Strong air movement and cloud formation makes it a turbulent and dusty zone. We can observe different weather phenomena here such as rain or fog.
2. Stratosphere: This layer of atmosphere extends upto $ \sim 50\;{\rm{km}}$ from the sea level. In this region, air contains mainly ${{\rm{N}}_{\rm{2}}},{{\rm{O}}_2},{{\rm{O}}_3}$ and some ${{\rm{H}}_2}{\rm{O}}$ vapors. We don’t have any clouds here or any weather related phenomena which make it comparatively calmer and clearer enabling us to fly our airplanes here.
3. Mesosphere: This layer of atmosphere extends upto $ \sim 80\;{\rm{km}}$ from the sea level. This is the region in which meteorites get burnt up when they enter from space.
4. Thermosphere: This layer of atmosphere extends upto $ \sim 400\;{\rm{km}}$ from the sea level. As the name suggests, in this atmospheric layer, temperature comes into play as it rises very rapidly as we move up. Radio waves transmitted by us on Earth’s surface are reflected back from here and we get radio transmission.
5. Exosphere: This is the outermost layer with space beyond it. The air is most thin here and thus very light gases such as ${{\rm{H}}_2}{\rm{,He}}$ are present here.

From the above discussion, we can see that ozone $\left( {{{\rm{O}}_3}} \right)$ is found in the stratosphere which is the second layer of the atmosphere.

Note:
The Stratosphere is just next to the troposphere and protects us from harmful ${\rm{UV}}$ radiation coming from the Sun but the emission from the troposphere itself has led to ozone depletion.