课件26张PPT。 Unit 4 Global warming Warming-up and lead-in
As we all know, global warming
is related to the use of energy.
And we depend on energy to do many things in our daily life. Some people even say we could
do nothing without energy. Then what do we use energy for? light things that use energy in your homeCD player mp4 television hairdryer fridge computer washing machine1. look at the pictures and list
the things that use energy
in your home.a coal power stationoil refinery
(炼油厂)nuclear power plant(工厂)2. List some energy sources according to the pictures. coalnuclearoilRenewable or non-renewable?(SB P25)√(1)(2)(3)2. List some energy sources according to the pictures. (4)(5)(6)a windmill(风车)watera hydro-electric dam(水力发电大坝)windsolar
panels
(太阳能
电池板)solar
powerRenewable or non-renewable?√renewablenon-renewablefossil fuels(矿物燃料)carbon dioxide( Co2 )global warming3.negative effects of using energy sourcesHow does global warming come about?Have you ever seen a greenhouse?How does it work?The glass traps the heat from the sun, making the air in the greenhouse warm so that plants can grow better.The air inside is warm because the glass trap 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”?
What do you think greenhouse gases do?greenhouse effectWhat’s greenhouse gases effect?Greenhouse gases perform the same fun_ction as the glass in a greenhouse --- they trap the heat of the sun and keep the air surrounding the earth warm.
It is called the greenhouse effect.二. ReadingThe Earth is becoming Warmer ---But Does it Matter?(1)What is the main topic?
The earth.
Global warming.
C. Becoming warmer doesn’t matter.
(2)What is the writing style?
Expositive说明文
Descriptive. 记叙文
C. Argumentative.议论文
Step I Fast Reading1.Skim the title and think:2. Skim the text and divide it into four parts. Para. 1Para. 2-5Part1Part2Para. 6Part3Para 7Part4
Introduction Body Conclusion(3) The organization
of an expositive: IntroductionA titleBodyConclusion3.Match the main idea of each partPart 1(para1)Part 2
(para 2—5)Part 3（Para 6)
Part4(para 7)B. It is up to readers to decide whether they should stop global warming or notA. state how global warming comes about C. introduce the issue
of global warmingD. list two different attitudes towards global warmingMain ideas of each part
Part 1: introduce a debate over the issue of global warming
Part 2:state how global warming comes about
Part 3:list two different attitudes among scientists towards global warming
Part 4:It’s up to readers to think and decide whether people should do something about global warming or not.Writing techniques
Using a question leaving readers to think over the issue
Giving examples, using graphs, explanation
Raising a question
Giving examples, making contrast4. Match the writing techniquesABDCABCDStep II Careful Reading1. Part 1 (Para 1)Listen and answer the following questions:(1).Who wrote the magazine article?
(2).What is the name of the magazine?→ Earth Care.→ Sophie ArmstrongStep II Careful Reading2. Part 2 A. Para 2Listen, read at the same time, and think:(1).What is Graph 1 about?
(2).How has the global warming come about?Graph 1 shows the temperature _______of
___ degree Fahrenheit from ____ to ____.increaseone18602000It is ______ ______ that has
caused this global warming.humanactivityStep II Careful Reading2. Part 2 B. Para 3(1). Listen and choose:
Greenhouse gases include ___, ___ and ___.
A. water vapor; B. natural gas; C. carbon dioxide
D. methane ; E. fossil fuels.
Key words in Para3 include ___ and ___.
A. coal ; B. greenhouse gases ; C. 33oC ;
D. Energy ; E. greenhouse effectACDBEStep II Careful Reading2. Part 2 B. Para 3(2). Read and fill in the blanks( Key Words Analyze):
A greenhouse is made of
_____ which traps ____
from the ____ and makes
the ____ inside _____ so
the ____ can grow during ____ weather.Greenhouse effect happens when gases like _____ _____
trap ___ from the ____ and therefore ____ the earth.
glassheatheatsunsunairwarmwarmcarbondioxideFirst, read P25/1 Now, read P26/Para3 againThen, enjoy a flash about
greenhouse effectplantscoldStep II Careful Reading2. Part 2 C. Para 4&5
The levels of Co2 have increased greatly over the past
150 years.
(2) Graph 2 show Co2 content in the atmasphere,1957-1977.
(3) Most scientists accept the data made
by Janice Foster.
(4) The burning of fossil fuels lead to the increase in Co2.
(5) The amount of warming could be as high as 1 degree.
First listen, then read and do “T” or “F” exercise:50(Para4, Line 1-2)FFFTT(Graph 2)All(Para5, Line1)Charles Keeling(Para4, Line 3)(Para5)5 degrees(Para5, the last line)The different ideas between Dr. Janice Foster & George Hambleygo upcatastrophevery seriouspositiveproducea greater range of animalsStep II Careful Reading3. Part 3 (Para 5)The author probably agrees that___.
actually global warming is good for human.
catastrophes will happen eventually due to global warming.
a lot remains to be found out about the effects of global warming
Step II Careful Reading4. Part 4 ( Para 7)cStop global warming
Good bye
