Question

Ozone hole refers to

• A. Hole is ozone layers
• B. Reduction in thickness of ozone layer in stratosphere
• C. Reduction of thickness of ozone in troposphere
• D. Increase concentration of ozone

Answer 1

The correct option is B Reduction in thickness of ozone layer in stratosphere

When the oxygen-depleting substances like CFCs, HFCs, methyl bromide etc. find their way to the stratosphere, the UV rays spilt them to release the reactive species of chlorine and bromine. These reactive species react with the ozone to release the oxygen, thereby causing the depletion of ozone. The ozone hole is the place where the thickness of the ozone layer is very thin and the concentration is less than 220 DU. It is seen over Antarctica due to the process of polar vortex and formation of polar stratospheric clouds.

Hence, the correct answer is 'Reduction in thickness of the ozone layer in stratosphere'.