SALWANIE MUHAMAD (94899) NOOR FARRA SHAFINAZ BT ZAINAL ABIDIN (95206)

1. PRESENTERS SALWANIE MUHAMAD (94899) NOOR FARRA SHAFINAZ BT ZAINAL ABIDIN (95206) NORHANIZA CHE MOHAMED (95214) NORHAZLINA BT MAT ARIFIN (95216) NEXT

2. LESSON PLAN • Date: 12 August 2008 Class: 4 Science 1 • Time: 80 minutes • Number of students: 25 students • Students’ age: 16 years old • Topic: Endangered Ecosystem • Subtopic: 1) Ozone Layer Thinning • 2) Green House Effect • Main Objective: Students will learn about the effect of ozone layer thinning and green house towards ecosystem. • Specific Objectives: • At the end of this lesson, students should be able to : • Make an analogy of global warming • Explain the phenomenon of green house effect • Explain the phenomenon of ozone layer thinning. • Make the connection between green house effect and global warming phenomenon. BACK NEXT

3. ENDANGERED ECOSYSTEM GREEN HOUSE EFFECT OZONE LAYER THINNING

4. THE INCREASING OF CARBON DIOXIDE GASES IN ATMOSPHERE SINCE 1950 -1985 CARBON DIOXIDE (BILLION TAN) YEAR What are the relationship between the year and the level of CO2??? NEXT BACK

5. O O C FUNCTION?? To carry out photosynthesis process. EFFECTS OF INCREASING OF CO2 ?? The thinning of ozone layer and green house effect are caused by the increasing of the carbon dioxide gases. NEXT BACK

6. OZONE LAYER THINNING

7. Ozone What is Ozone? • The ozone layer is a portion of earth’s atmosphere that contains high levels of ozone. The atmosphere is divided into five layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere.  • The troposphere is the layer closest to earth and is where all weather happenings occur.  The stratosphere is located directly above the troposphere, about 10 - 50 kilometres above the planet, and houses the ozone layer at an altitude of 20-30 kilometres.  NEXT

8. Earth's atmosphere is divided into layers, which have various characteristics. Source:  NOAA Aeronomy Laboratory, 1998 NEXT BACK

9. The ozone found in our atmosphere is formed by an interaction between oxygen molecules (composed of two oxygen atoms) and ultraviolet light. • When ultraviolet light hits these oxygen molecules, the reaction causes the molecules to break apart into single atoms of oxygen. UV light + O2 --> O + O • These single atoms of oxygen are very reactive, and a single atom combines with a molecule of oxygen to form ozone (O3), which is composed of three atoms of oxygen 2O + 2O2 --> 2O3 BACK NEXT

10. Why is Ozone Important? • It filters out harmful UV radiation. This will prevent UV rays from reaching the earth’s surface as excessive exposure to UV radiation that may cause skin cancer. NEXT BACK

11. Ozone Depletion • It is caused by the release of the chlorofluorocarbons (CFCs) into the atmosphere. • It occurs in the stratosphere. • The uses of CFCs include : - in air conditioners as a coolant - for cleaning electronic circuit boards - as a solvent - for making foam product - as a propellant in aerosol cans NEXT BACK

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13. The action of CFCs towards chlorine atoms. NEXT BACK

14. As a propellant in aerosol cans In air conditioners The uses of CFCs include For making foam product For cleaning electronic circuit boards As a solvent NEXT BACK

15. PERCENTAGES OF RESPONSIBILITY FOR OZONE DAMAGE EVERY YEAR Can you guess???? Human Activities ( 1–5 )% ( 15–20 ) % Volcanic Eruption ( 75–85 ) % Natural Sources BACK NEXT

16. EFFECTS OF OZONE LAYER THINNING BACK NEXT

17. The effects are : • skin cancer • premature aging • cataracts • immune system suppression • agricultural damage • ocean stress SKIN CANCER BACK NEXT

18. What Can You Do As Human To Overcome The Ozone Layer Thinning Problems? • Make sure all refrigerants from your car are recovered and recycled during servicing. • Remove the refrigerants from household refrigerators, air conditioners, and dehumidifiers before disposing of them. BACK NEXT

19. Be sure your tires are properly inflated. • Keep car, boat, and other engines tuned up according to manufacturers' specification. • Carpool, use public transportation, bike, or walk whenever possible. • Use environmentally safe paints and cleaning products whenever possible. BACK NEXT

20. Skin cancer Premature aging Ocean stress Serious health and environmental problems on overexposure to UV radiation Agricultural damage Cataracts Immune system suppression BACK NEXT

21. GREEN HOUSE EFFECT BACK NEXT

22. What Is The Green House Effect? • It is responsible for keeping the earth warm and suitablefor life. • It is the rise in temperature the earth experience because certain gases in the atmosphere [water vapour, carbon dioxide, methane, nitrous oxide, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6)] that trap energy from sun. • The main sources- from the combustion of fossil fuels (burning coal), automobiles and factories. BACK NEXT

23. sun Some infrared radiation passes through atmosphere and some is absorbed and reemitted in all directions thus warming the earth’s surface and the lower atmosphere. Some solar radiation is reflected by the earth and the atmosphere. Solar radiation passes through the clear atmosphere. Infrared radiation is emitted from the earth’s surface. Most radiation is absorbed by the earth’s surface and warms it. earth BACK NEXT

24. Sulfur hexafluoride (SF6) Water vapour Methane Nitrous oxide What Are Greenhouse Gases? Carbon dioxide Hydrofluorocarbons (HFCs) Perfluorocarbons (PFCs) BACK NEXT

25. GLOBAL WARMING • Refers to possible excessive heating of the earth surface from the addition of greenhouse gases to the atmosphere and from thinning of the ozone layer. The heat that trap will increase the temperature of earth (climate changes) Sea levels rise Flash floods BACK NEXT

26. FINISHTHANK YOU