选修六 4.5Unit 4 Reading.ppt
新课标人教版课件系列,高中英语选修(模块）6-4.5,Reading,What is the greenhouse made and used for?,A greenhouse is made of glass and is used for growing plants,especially during cold weather.,How does it work?The air inside is warm because the glass traps the heat from the sun and keeps it from escaping.This makes the greenhouse heat up and so the plants can grow throughout the cold period.,What are the“greenhouse gases”?In the atmosphere surrounding the earth there are gases,which are called“greenhouse gases”,including carbon dioxide,methane(甲烷,沼气)and water vapor.,What do you think greenhousegases do?They trap heat from the sun and therefore warm the earth.,(Paragraph 1),Introduce a debate over the issue of global warming.,Raising a question,(Paragraphs 2-4),Illustrate how global warming comes about.,Giving examples,using graphs,explanation.,(Paragraphs 5-10),List two different attitudes among scientists towards global warming.,Giving examples,making contrast.,(Paragraph 11),Its up to readers to think and decide whether people should do something about global warming or not.,Using a question,leaving readers to think over the issue.,浓度单位,Glance quickly at the magazine article and answer the questions.Who wrote the magazine article?What is the name of the magazine?Sophie Armstrong wrote the magazine article.The name of the magazine is Earth Care.,What are the names of the three scientists mentioned in the article?They are Dr.Janice Foster,Charles Keeling and George Hambley.,3.What do they think about global warming?Do they agree with one another?They dont agree with each other.Dr.Janice Foster thinks the effects of global warming could be very serious.,George Hambley thinks global warming will be mild with few bad environmental consequences.Charles Keeling believes it is the burning of more and more fossil fuels that is resulting in a big increase in carbon dioxide.,What are the two graphs about?Graph I shows the temperature increase of one degree Fahrenheit between 1860 to 2000.Graph 2 is about the carbon dioxide content in the atmosphere,1958-1990.,What is the main topic of the article?Global warming/the warming of the earth.,2.True:3,5,6,7,8 False:1,2,4,9,10Correct sentences:1.The temperature last century increased much.2.Not everyone believes that global warming is caused by human activities.,4.Natural gas is not a greenhouse gas but a fossil fuel.9.George Hambley thinks that more carbon dioxide is a positive thing and it will make plants grow faster.10.It is unknown what the effects of global warming will be.,DebateInstructions Get into groups of six.Decide which three in your group are going to agree with the statement(Group A)and which three are going to disagree with the statement(Group B).,Group A discuss why they agree with the statement;Group B discuss why they disagree.Group A and B get together.Tell each other the reasons why agree or disagree with the statement.,Supplementary materials for debating Global warming 1.The planet has warmed anywhere from 0.5 to 1.0C(1 to 2F)over the last century.,This small amount makes a huge difference,causing glaciers to melt and,potentially(潜在的),sea level to rise.We could see even more of this in the future,(maybe another 3C,or 5F),global warming,global warming,2.A definition of global warming would have to include a measurable,consistent temperature rise,like the one we have seen in recent history.A question remains Is it an unusual change?Much debate about that one.,3.The earth gets one kind of energy(visible light)from the sun and gives off another kind(infrared红外线).This kind is what gets trapped by green house gases(GHGs)in the atmosphere.,Green house gases4.The global warming green house effect really is a bogus(假的)term.A greenhouse keeps warm by physically trapping the air inside and preventing convection(对流).,The atmosphere helps keep the planet warm by trapping outgoing radiation instead.,5.The leading gasses are Carbon-dioxide,Methane,Ozone(臭氧)and Nitrous Oxide(一氧化二氮).Gas analyzers show the concentrations of this stuff have increased somewhat since the beginning of the industrial revolution.,6.The greenhouse effect raises the average temperature of the Earth by more than 30 degrees,so without it the Earth would be a very cold place!,green house effect,green house effect,GREENHOUSE Feeling helpless to do anything about global warming?Find out how one family cut their own personal greenhouse-gas emissions by 65 percent-and how you can do the same.,green house effect,Homework 1.Read the passage again and review the new words and expressions.2.Prepare the debate in groups.3.Preview Using Language-WHAT CAN WE DO ABOUT GLOBAL WARMING?,
