unit4 Global Warming(浙江省台州市)

课件20张PPT。Unit 4 Global WarmingPicture readingScanningThe 1st graph shows the global t between 1860 and . The temperature i and decreased over this period but on the whole it i by around one degree Fahrenheit. During this time, the earth reached its l temperature in about 1910 and its highest in . There was a steady i in the temperature during the 20 years after 1980. We can see from the graph that the earth has become w since early last century.emperature2000ncreasedncreased owest2000ncreasearmerScanningThe 2nd graph shows the amount of c d in the atmosphere from to 1997. The Co2 c steadily i over this forty-year period. It went up from 315 to parts p million. arbonioxide1957ontentncreased370erTip: While reading a graph, you’d better pay attention to the numbers.Reading: The Earth is Becoming Warmer-But Does It Matter?Sophie Armstrong 1.Who wrote the magazine article? 2. What is the name of the magazine?Glance and Answer!Earth Care1. How has global warming come about?
2. Does it matter?Careful Reading1. How has global warming come about?Careful ReadingThere is a fierce debate over it. Human activity
Just a natural phenomenon Dr Janice Foster2. Does it matter?Careful ReadingPositive effects Negative effects cause the sea level to rise
severe storms
droughts
famines
the spread of diseases
destruction of speciesPositive effects Negative effects cause the sea level to rise
severe storms
droughts
famines
the spread of diseases
destruction of speciesPositive effects Negative effects make plants grow faster
crops will produce more
a greater range of animals
make life better George HambleyTrue and False?1.The temperature last century didn’t increase much.
2.Everyone believes that global warming is caused by the activities of humans.
3.Janice Foster believes that global warming is caused by burning fossil fuels. F FTP1: … it is a rapid increase compared to most natural changes… P2: … there is fierce debate over it… 4.Natural gas is a greenhouse gas.
5.Carbon dioxide is a byproduct of burning fossil fuels. F TP3: Fossil fuels: coal, natural gas and oil. 6.People accept Charles Keeling’s data because he took accurate measurements. T7.Flooding could be one of the effects of future global warming.
8.George Hambley believes scientists are just guessing about the effects of global warming.
9.George Hambley is worried about the effects of carbon dioxide on plant growth.
10.It is clear what the effects of global warming will be. T T F FP10: positive P11: No one knows… P10: speculationThe author probably agrees that ________.
A. Actually global warming is good for man.B. We should do nothing about the global warming.C. Catastrophes will happen if the globe keeps on warming.D. A lot remains to be found out about the effects of global warming.Further understanding Idea-sharingShould we do something about global warming ?Group AagreereasonsGroup BdisagreereasonsDebate