Ozone layer depletion occurs when chlorine and bromine atoms in the atmosphere destroy ozone molecules in the stratosphere. The ozone layer normally protects life on Earth by absorbing 97-99% of the sun's harmful ultraviolet radiation. Common ozone-depleting substances include chlorofluorocarbons found in refrigerators and air conditioners as well as halons from fire extinguishers. If the ozone layer was destroyed, millions of people could develop skin cancer and other diseases from increased UV exposure. International agreements like the Montreal Protocol have sought to phase out ozone-depleting substances to allow the ozone layer to recover.
2. What is ozone?
Ozone, or trioxygen,
is an inorganic
molecule with the
chemical formula O ₃.
It is a pale blue gas
with a distinctively
pungent smell.
Nearly 90% of the
Earth's ozone is in the
stratosphere and is
referred to as the
ozone layer
3. What is Ozone
Layer
• The ozone layer is a region in the
earth’s stratosphere that contains
high concentrations of ozone and
protects the earth from the
harmful ultraviolet radiations of
the sun. The ozone layer is found
in the lower portion of the earth’s
atmosphere. It has the potential
to absorb around 97-99% of the
harmful ultraviolet radiations
coming from the sun that can
damage life on earth. If the ozone
layer was absent, millions of
people would develop skin
4. What is ozone
depletion?
Ozone layer depletion
is the thinning of the
ozone layer present in the
upper atmosphere. This
happens when the
chlorine and bromine
atoms in the atmosphere
encounter ozone and
destroy the ozone
molecules. One chlorine
can destroy 100,000
molecules of ozone.
5. Substances Depleting
the Ozone Layer
Ozone-Depleting
Substances
Sources
Chlorofluorocarbons
(CFCs)
Refrigerators, air-
conditioners, solvents, dry-
cleaning agents, etc.
Halons Fire-extinguishers
Carbon tetrachloride Fire extinguishers, solvents
Methyl chloroform Adhesives, aerosols
Hydrofluorocarbons
fire extinguishers, air-
conditioners, solvents
7. Solutions to Ozone Layer Depletion
• Avoid Using ODS
• Minimize the Use of Vehicles
• Use Eco-friendly Cleaning Products
• Use of Nitrous Oxide should be Prohibited
8. Facts on Ozone Layer
• The word "ozone" means smelly in Greek because the gas has a strong
odor.
• CFC molecules are highly stable and can last for up to 100 years.
Unfortunately, this gives them plenty of time to find their way to the ozone
layer.
• Ultraviolet rays can also have bad effects on nature. They can kill plankton,
which is a major source of food in the ocean's food chain.
• The ozone layer over Antarctica is very thin. It is sometimes called the
"hole" in the ozone layer.
• In 1994, the General Assembly proclaimed 16 September as the
International Day for the Preservation of the Ozone Layer, commemorating
the date in 1987 on which the Montreal Protocol on Substances that Deplete
the Ozone Layer was signed.
• In 1985 Jonathan Shanklin was a junior researcher at BAS when he
hole in the invisible shield that protects us from solar radiation.