1、Unit 4 Global WarmingUnit 4 Global WarmingReadingReading ReadingThe Earth is Becoming Warmer-But Does It Matter?Go through the text and think about how to divide the whole passage according to the main idea.Paragraph 1Paragraphs 2&5Paragraph 6Part1Part2Part4Main idea of the textPart3Paragraph 7H

2、ow has global warming come about? List two different attitudes among scientists towards global warming.The earth is becoming warmerShould we do anything?Finish exercise 2 on Page 27.Para.1: Question : How has this global warming come about? Para.2 It is human activity that has caused this global war

3、ming rather than a random but natural phenomenon.全球變暖正是人類活動導致而成的，而全球變暖正是人類活動導致而成的，而不是隨意的自然現象。不是隨意的自然現象。How has human activity caused this global warming?Look at the two graphs .Graph 1:Graph 2:19573151957nFrom the two graphs, can you find some relationship between them? The more CO2, the higher temp

4、erature.nWhy does more CO2 cause higher temperature?Graph 1:Graph 2:Greenhouse gases _ the heat of the sun and therefore _ the earth.It is known as _.greenhouse effecttrapwarmPara.3 (Line 24-36)carbon dioxideFossil Fuelcoal oil gas producenWhy is extra carbon dioxide added into the atmosphere? Para.

5、3 (Line 18-23)& Para.5nIs “global warming” beneficial or harmful to us? Does it matter? Para.61. cause the sea level to rise2. severe storms3. floods4. droughts5. famines6. the spread of diseases7. disappearance of speciesPositive effects Negative effects 1. make plants grow quicker2. crops will

6、 produce more3. a greater range of animals4. make life betterDebateABA : We shall do something about global warming.B: We shall do nothing about global We should do nothing about global It is human activity that has caused this global warming rather than a random but natural phenomenon.全球變暖正是人類活動導致而

7、成的，而全球變暖正是人類活動導致而成的，而不是隨意的自然現象。不是隨意的自然現象。What should we do?DSuggestions 1. Switch off the electrical appliance when not using them.2. Put more clothes instead of turning on the heater.3. Walk or ride a bike if you can instead of driving cars.4. Try not to buy unnecessary shoes and clothes.5. Make an effort to save every drop of water and recycle the u