Which gas protects the earth from the harmful ultraviolet rays?

Nitrogen and oxygen in our atmosphere protect us from UV-C and more energetic radiation. Some of the oxygen turns into ozone thereby. Ozone protects us from UV-B.

UV-A arrives at Earth's surface Ozone gas is found in the stratosphere of the atmosphere. It is not a uniform layer. Its thickness varies in gradation.

Ozone is formed by the action of sun's rays on oxygen molecules However, the rate of ozone depletion is faster than its production. Depletion is caused due to CFCs(chloro flouro carbons) which are found in refrigerators, air conditioners and aerosols(used in spray cans).

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