International Ozone day is celebrated on

16th September
7th December
30th March
22nd April

The correct answer is (a) 16th September.

International Ozone Day is celebrated on September 16 each year to raise awareness about the importance of the ozone layer and the dangers of ozone depletion. The day was established by the United Nations General Assembly in 1994, on the 15th anniversary of the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer.

The ozone layer is a region of Earth’s stratosphere that absorbs most of the Sun’s ultraviolet radiation. It contains high concentrations of ozone (O3) relative to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth’s atmosphere as a whole is about 0.3 parts per million.

The ozone layer is important because it protects life on Earth from harmful ultraviolet radiation. Ultraviolet radiation can cause skin cancer, cataracts, and other health problems. It can also damage plants and animals.

Ozone depletion is the thinning of the ozone layer in Earth’s stratosphere. The ozone layer absorbs most of the Sun’s ultraviolet radiation, which is harmful to life on Earth. Ozone depletion is caused by human activities, such as the release of chlorofluorocarbons (CFCs) into the atmosphere. CFCs are chemicals that were once used in refrigerators, air conditioners, and other products. They are now banned in most countries, but they continue to break down in the atmosphere and contribute to ozone depletion.

International Ozone Day is an opportunity to raise awareness about the importance of the ozone layer and the dangers of ozone depletion. It is also an opportunity to celebrate the progress that has been made in protecting the ozone layer.

The other options are incorrect because they are not the dates on which International Ozone Day is celebrated.