1. Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Do Now: List 3 things you already know about ozone depletion
Causes
Effects
Solutions
What is ozone?

2. Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
What is Ozone?
Altitude (Kilometers)
“Good Ozone”
Smog Ozone
“Bad Ozone”
Ozone Amount
Molecules of ozone consist of three oxygen atoms.
Ozone at ground level is a pollutant.
Ozone layer at stratosphere serves an important function.

3. What radiation is light made of?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
What radiation is light made of?
Sunlight
spectrum
Sunlight is made of UV (ultraviolet) radiation, visible light, infrared radiation, microwaves and radio waves.
UV radiation is high energy radiation

4. What is the role of the ozone layer?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
What is the role of the ozone layer?
The ozone layer does not really “shield” us or “reflect” harmful UV radiation.
The ozone layer protect us from UV by absorbing UV energy before it can reach the ground

5. How has the ozone layer changed over time?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
How has the ozone layer changed over time?
Beginning in the 1970s, scientists found evidence from satellite data that the ozone layer was in trouble.
There are two holes in the ozone layer, one over Antarctica, the other appeared over the Artic.

6. How has the ozone layer changed over time?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
How has the ozone layer changed over time?
Beginning in the 1970s, scientists found evidence from satellite data that the ozone layer was in trouble.
There are two holes in the ozone layer, one over Antarctica, the other appeared over the Artic.

7. How has the ozone layer changed over time?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
How has the ozone layer changed over time?
Ozone layer decreased (depleted) from 1980 to 1996.
Then it increased since 1998

8. What Causes Ozone Depletion?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
What Causes Ozone Depletion?
The production and emission of CFCs, ChloroFluoroCarbons, is by far the leading cause of ozone depletion. CFCs came to be used in refrigerators, home insulation, plastic foam, and throwaway food containers. Many countries have called for the end of CFC production. However, even if CFCs were completely banned, problems would remain. There would still be no way to remove the CFCs that are now present in the environment.
When CFCs reach the stratosphere, the ultraviolet radiation from the sun causes them to break apart and release chlorine atoms which react with ozone, starting chemical cycles of ozone destruction that deplete the ozone layer. One chlorine atom can break apart more than 100,000 ozone molecules
Which gases damage the ozone layer?
What products are there that contain or use CFC´s ?
CFCs, (ChloroFluorCarbons)
Coolant in refrigerator and freezers
Production of plastic foams
Propellants in aerosol cans
Air conditioners

9. What Causes Ozone Depletion?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
What Causes Ozone Depletion?
The main cause of ozone depletion is the release of gases CFC’s into the atmosphere
It can take 5-15 years for a CFC molecule to migrate to the stratosphere.

10. Effects of UV on living things
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Effects of UV on living things
Every time even a small amount of the ozone layer is lost, more ultraviolet light from the sun can reach the Earth.
Every time 1% of the ozone layer is depleted, 2% more UV-B is able to reach the surface of the planet. UV-B increase is one of the most harmful consequences of ozone depletion because it can cause skin cancer.
The increased cancer levels caused by exposure to this ultraviolet light could be enormous. The EPA estimates that 60 million Americans born by the year 2075 will get skin cancer because of ozone depletion. About one million of these people will die.
In addition to cancer, some research shows that a decreased ozone layer will increase rates of malaria and other infectious diseases. According to the EPA, 17 million more cases of cataracts can also be expected.
The environment will also be negatively affected by ozone depletion. The life cycles of plants will change, disrupting the food chain. Oceans will be hit hard as well. The most basic microscopic organisms such as plankton may not be able to survive. If that happened, it would mean that all of the other animals that are above plankton in the food chain would also die out. Other ecosystems such as forests and deserts will also be harmed.

11. Effects of UV on living things
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Effects of UV on living things
Every time even a small amount of the ozone layer is lost, more ultraviolet light from the sun can reach the Earth.
Every time 1% of the ozone layer is depleted, 2% more UV-B is able to reach the surface of the planet. UV-B increase is one of the most harmful consequences of ozone depletion because it can cause skin cancer.
The increased cancer levels caused by exposure to this ultraviolet light could be enormous. The EPA estimates that 60 million Americans born by the year 2075 will get skin cancer because of ozone depletion. About one million of these people will die.
In addition to cancer, some research shows that a decreased ozone layer will increase rates of malaria and other infectious diseases. According to the EPA, 17 million more cases of cataracts can also be expected.
The environment will also be negatively affected by ozone depletion. The life cycles of plants will change, disrupting the food chain. Oceans will be hit hard as well. The most basic microscopic organisms such as plankton may not be able to survive. If that happened, it would mean that all of the other animals that are above plankton in the food chain would also die out. Other ecosystems such as forests and deserts will also be harmed.

12. Effects of UV on living things
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Effects of UV on living things
What are the effects of UV on living things?
In humans:
Mutation in the DNA: skin cancer
Damage eyes & cataracts
Decrease organisms’ resistance to disease
In the environment
Kill phytoplankton in the oceans
Disrupt food chains in the ocean
cataracts
Skin cancer

13. A world without Ozone Layer
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
A world without Ozone Layer
In the absence of an ozone layer, life could only evolve under water

14. A world without Ozone Layer
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
A world without Ozone Layer

15. 15. What can you do to make a difference?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
15. What can you do to make a difference?
What can you do to solve the problem?
Because CFCs are so widespread and used in such a great variety of products, limiting their use is hard. Also, since many products already contain components that use CFCs, it would be difficult if not impossible to eliminate those CFCs already in existence.
The CFC problem may be hard to solve because there are already great quantities of CFCs in the environment. CFCs would remain in the stratosphere for another 100 years even if none were ever produced again.
Despite the difficulties, international action has been taken to limit CFCs. In the Montreal Protocol (1987), 30 nations worldwide agreed to reduce usage of CFCs and encouraged other countries to do so as well.
By the year 2000, the US and twelve nations in Europe have agreed to ban all use and production of CFCs. This will be highly significant, because these countries produce three quarters of the CFCs in the world.
Many other countries have signed treaties and written laws restricting the use of CFCs. Companies are finding substitutes for CFCs, and people in general are becoming more aware of the dangers of ozone depletion.
What is being done about ozone depletion at the international level?
In the Montreal Protocol (1987), 30 nations worldwide agreed to reduce usage of CFCs

16. How has the production of CFC’s changed in the last years?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
How has the production of CFC’s changed in the last years?
CFC’s production increased from 1950 to 1987.
After the Montreal protocol, CFC’s production decreased steadily.

17. 15. What can you do to make a difference?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
15. What can you do to make a difference?
What can you do to solve the problem?
As individuals, we also contribute to the problem. Now it's time to become part of the solution. Here's what you can do. The pipes of refrigerators and air-conditioners contain CFCs. Avoid leakages from these appliances by following these tips:
Don't scrape the ice from inside freezers using knives or other hard objects which may puncture the inside-casing.
If your refrigerator, freezer or air-conditioner (especially in your car) needs a repair, go to a reputable dealer and ensure that the service mechanic collects the gas so that it does not escape into the atmosphere. Also ensure that a test for leaks is carried out before re-gassing.
When purchasing new air-conditioners or refrigerators, ensure that they do not use CFCs.
What can you do to make a difference?
Avoid using and buying products made with CFCs
For example, use a reusable cup instead of a plastic foam one
Have home and car air conditioners checked for leaks
Safe disposal of appliances (refrigerators, air conditioners)
Reduce the use of air conditioners

18. 15. What can you do to make a difference?
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
15. What can you do to make a difference?
Ozone Depletion Summary
Causes
Molecules
Effects
Solutions
CFCs emissions from
1. Propellants in aerosol cans
2. Coolant in refrigerator & freezers & air conditioners
3. Production of plastic foams
CFCs
In humans
Sunburn & skin cancer
Damage eyes & cataracts
Decrease organisms’ resistance to disease
In the environment
Damage tissue in plant leaves and phytoplankton in the oceans
Disrupt food chains in the ocean
Laws & Legislation prohibiting CFCs products
Avoid using and buying products made with CFCs
Use reusable cup instead of a plastic foam one
Have home and car air conditioners checked for leaks
Safe disposal of refrigerators and air conditioners

19. Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Write a paragraph to explain why the amount of UV (Ultraviolet radiation) reaching the surface of the Earth is increasing, and describe its effects on the living things, and suggest one action that could help solve the problem. In your answer be sure to include
an explanation of why the amount of UV reaching the surface of the Earth is increasing or one human activity that is thought to contribute to ozone depletion
one negative effect of ozone depletion on the organisms
one possible solution to this problem
The production of CFCs in aerosols, refrigerators and plastic foams destroy the ozone layer.
One negative effect of ozone depletion is the increment of skin cancer in humans.
One possible solution is the use of reusable cups and plates instead of foam disposable ones.

20. Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Do Now: List 3 things you already learned about ozone depletion
One of the causes of ozone depletion is ________________
One of the effects on living things is ____________________
One possible solution is _____________________________
What is ozone?

21. Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
4. What will the continued depletion of the ozone layer most likely cause?
an increase in skin cancer among humans
a decrease in atmospheric pollutants
C) an increase in marine ecosystem stability
D) a decrease in climatic changes
5. The construction of a new coal-burning power plant would have the greatest impact on which environmental issue?
A) depletion of the ozone B) production of acid rain
C) release of radiation D) increase in deforestation
6. The ozone layer of Earth’s atmosphere helps to filter ultraviolet radiation. As the ozone layer is depleted, more ultraviolet radiation reaches Earth’s surface. This increase in ultraviolet radiation may be harmful because it can directly cause
A) photosynthesis to stop in all marine organisms
B) abnormal migration patterns in waterfowl
C) mutations in the DNA of organisms
D) sterility in most species of mammals and birds

22. Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
7. Base your answer to the following question on the diagram below and on your knowledge of biology. The diagram shows some of the gases that, along with their sources, contribute to four major problems associated with air pollution.
Explain why damage to the ozone shield is considered a threat to many organisms.
If the amount of ultraviolet (UV) radiation reaching the Earth will increase,
then, UV radiation will kill phytoplankton in the oceans and disrupt the food chains.

23. Decomposition of the Ozone Layer
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Decomposition of the Ozone Layer
The Earth has long been protected from the harmful radiations of the Sun by a layer of the
atmosphere known as the ozone layer. This layer absorbs ultraviolet light. Recent evidence
indicates that this protective layer is starting to decompose and "holes" are being formed.
The first "hole" was observed in 1983 over Antarctica. Now there is evidence of a second
"hole" over Norway. It is believed that the atmosphere has had an annual ozone loss of three
percent.
Some scientists believe that the "holes" are linked to the use of certain chemicals such as
chlorofluorocarbons (CFC's). CFC's are found in some aerosol sprays, refrigerants, and even
in styrofoam. When CFC's are exposed to sunlight, chlorine is released from the CFC's. This
chlorine acts as a catalyst in the breakdown of ozone. Other scientists believe that the "holes"
are related to solar activity, changing weather patterns, and volcanic activity.
Whatever the cause, scientists agree that the potential dangers are significant. The
Environmental Protection Agency (EPA) estimates that a one percent drop in global ozone
could cause an additional 20,000 cases of skin cancer in the United States. Increases in
ultraviolet radiation could also increase the mutation rate in plants, animals, and
microorganisms, endangering the existence of some life forms.

24. Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
8. Decomposition of the ozone may lead to an increase in mutations because
A) plants can only utilize visible light for photosynthesis
B) it allows more ultraviolet rays to penetrate the atmosphere
C) changing weather patterns act as selecting agents
D) more free oxygen will be available, causing a decrease in carbon dioxide
9. Based on the reading passage, which statement can be made about the decomposition of the ozone layer?
A) The decomposition is due to very reactive oxygen.
B) The decomposition rate is increasing three percent every ten years.
C) "Holes" in the ozone layer are caused by ozone decomposition.
D) All scientists agree on the cause of the decomposition of the ozone layer.
10. When released, the chlorine in the chlorofluorocarbons
A) causes an increase in the pH of the atmosphere
B) adds oxygen to ozone molecules
C) produces acid rainfall
D) functions as a catalyst

25. Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
Objective: Learn about Causes, Effects and Solutions of Ozone Depletion
Key Words: ozone, ozone layer, U.V. (ultraviolet radiation),depletion
11. Based on the reading passage, state one hypothesis to explain the appearance of "holes" in the ozone layer.
12. Describe one action that humans could take to decrease the rate of decomposition of the ozone layer.
Ozone "holes" are linked to the use of certain chemicals such as chlorofluorocarbons (CFC's). CFC's are found in some aerosol sprays, refrigerants, and even in styrofoam
Ozone "holes“ are related to solar activity, changing weather patterns, and volcanic activity.
Avoid using and buying products made with CFCs
For example, use a reusable cup instead of a plastic foam one.

26. More UV rays reach the Earth, increasing incidence of sunburn
1) In the early 1980's, scientists discovered holes in the ozone shield surrounding Earth.
State one negative effect this environmental change could have on humans.
More UV rays reach the Earth, increasing incidence of sunburn
Increased incidence of skin cancers and/or cataracts
Decreased humans’ resistance to disease