1. Ozone Depletion

2. Layers of the Atmosphere

3. Troposphere
Extends from the land or water surface up to
an elevation of about five miles in the polar
region.
Composed of water vapor and clouds
The layer where rainstorms are produced and
airplanes fly.

4. Stratosphere
• 30 miles above the earth and gets hotter as
you go higher

5. Mesosphere
• Extends another 20 miles and is
characterized by a cooler temperature.

6. Ozone Layer
• Ozonosphere
• Hovers on top of the stratosphere

7. Ozone (O3)
• A strong smelling, slightly bluish gas.
• Composed of threeoxygen atoms
• Regarded as “the Jekyll and Hyde” of the
atmosphere.
• About 90% of all ozone s located in the
upper regions of the stratosphere; the rest is
at ground level and is responsible for
warming the globe.

8. Depletion of Ozone Shield
• Ozone-depleting substances (ODS)
• Carbons
• Carbon tetrachloride
• Methyl chloroform
• Chlorofluorocarbons (CFCs)

9. CFCs
• Originally regarded as “wonder chemicals”
• Colorless
• Non-flammable
• Non-corrosive
• Non-toxic
• Cool refrigerators and air conditioners
• Clean delicate plastic foam
• Used in home insulation
• Propellant of aerosols

10. Cause of Depletion
• Once split apart into the stratosphere, CFC
molecules pluck off one of the three oxygen
atos in the ozone.
• A single chlorine atom can, over time,
destroy more than 100,000 ozone molecules
• CFC Emissions Around the Globe
• Western Europe and U.S contribute most og
the world’s CFC’s

11. Effects of Depletion
• If CFC usage continues unabated, more than 60
million addictional cases of skin cancer and one
million additional deaths will take place by the
year 2075.
• Make people more vulnerable to a variety of
infectious diseases including malaria.
• Can cause 17 million cases of cataracts
• UV-B radiation will disrupt the food chain
• Destroy microorganisms necessary to maintain
marine life. Destroy photosynthesis and
metabolism of plaktons and can cause mutation in

12. Solutions to Ozone Depletion
• Ban the use and production of CFC’s, halons, and
other ODSs
• Require all service stations and auto repair shops
to recycle CFCs
• Prohibit the sale of new CFC-laden products-from
refrigerators to dry-cleaning solvents
• Ban all cars equipped with CFC-using air
conditioners
• Prohibit the use of nearly all CFC’s in most
industrial processes exept in drug manufacturing
medical devices and military specifications that