What is Ozone?

Ozone is a form of oxygen. But unlike oxygen, ozone is a poisonous gas. Each ozone molecule is made of three oxygen atoms, so its chemical formula is 03. Ozone is formed when ultraviolet radiation causes oxygen molecules (02) in the upper layers of the atmosphere to split apart. If a freed oxygen atom (O) bumps into an oxygen molecule (02), the three oxygen atoms re-form as ozone (03 ).

Good and bad ozone

In the stratosphere (the layer that is about 15 – 50 kms above the earth’s surface), where ozone exists naturally, it prevents the sun’s ultraviolet rays from reaching the earth and thereby protects life.

In the atmospheric layer closest to the earth’s surface, due to pollution by vehicles, nitrogen oxides and Hydrocarbons levels increase. In the presence of sunlight, these chemicals form ozone.  This ozone can cause health problems like coughing, throat irritation, aggravation of asthma, bronchitis etc. It can also damage crops. While ozone in the stratosphere benefits life on Earth by blocking ultraviolet radiation from the Sun, ozone in the lower atmosphere can trigger health problems.

What is ozone depletion?

Chlorofluorocarbons (CFCs) are the primary Ozone depleting chemicals. They are used as refrigerants in refrigerators, air conditioners etc. They contain Chlorine.

Ozone depletion process

  • Step 1 : The CFCs generated as a result of human activities reach the ozone layer in the atmosphere
  • Step  2 : The UV radiation from the sun breaks the CFCs and releases Chlorine
  • Step 3 : The Chlorine atoms breaks the ozone molecule and thereby ozone depletion.

How ozone depletion affects us?

When the ozone layer gets depleted, the UV radiation of the sun striking the earth gets increased. This can cause genetic damage, skin cancer (melanoma and non-melanoma), premature aging of skin, cataracts and other eye damage and can also lead to immune system suppression. It can also have adverse effects on marine environment.

Preventive Measures

  • Choose a cleaner commute — car pool, use public transportation, bike or walk when possible.
  • Combine errands to reduce “cold starts” of your car and avoid extended idling.
  • Use environmentally safe paints and cleaning products whenever possible.
  • Some products that you use at your home or office are made with smog-forming chemicals that can evaporate into the air when you use them. Follow manufacturers’ recommendations for use and properly seal cleaners, paints, and other chemicals to prevent evaporation into the air.
  • Replace CFC’s with HCFCs.