What is the ozone layer and why is it important?

The ozone layer is a thin shield of gas in the stratosphere, about 10–30 km above Earth’s surface, composed mainly of ozone (O₃) molecules. It plays a vital role in absorbing the Sun’s harmful ultraviolet-B (UV-B) radiation, which can cause skin cancer, cataracts, and damage to DNA in living organisms. Without the ozone layer, life on Earth would be exposed to extreme radiation, severely affecting human health, agriculture, and marine ecosystems. In short, the ozone layer is Earth’s natural sunscreen, ensuring the survival of ecosystems and maintaining the planet’s balance. Protecting it is critical for sustaining life.