| Location |
Stratosphere, approximately 10-30 km above Earth’s surface. |
| Composition |
Composed of ozone (O3) molecules.
Unit of measurement: Dobsob Unit (DU) |
| Function |
Acts as a protective shield, absorbing and blocking a significant portion of harmful ultraviolet (UV) radiation from the sun. |
| Importance |
Essential for protecting life on Earth by preventing excessive UV radiation, which can harm living organisms and the environment. |
| Ozone-depleting Substances |
Threatened by ODS like chlorofluorocarbons (CFCs), halons, and other synthetic compounds commonly used in refrigeration, air conditioning, and aerosol propellants. |
| Montreal Protocol |
An international treaty adopted in 1987 to phase out the production and consumption of ODS, resulting in significant recovery of the ozone layer. |
| Current Status |
The ozone layer is in the process of recovery due to the success of the Montreal Protocol. |
| Environmental Impact |
Protects ecosystems, prevents skin cancer, cataracts, and other health issues in humans. |
| Additional Facts |
• The size of the ozone hole over Antarctica varies annually, opening in August and closing in November or December.
• Special winds caused by the Earth’s rotation create a unique climate over Antarctica, preventing mixing with surrounding air.
• When these winds subside, the hole closes. |