Unit 4 Global warming warming Up We depend on energy to do many things in our daily lives. For example, energy lights our cities and heats our buildings. What other things do we use energy for? Make a list of the things that consume from? Make another list of as many sources of energy as you can. These photos will help you a energy in your home, school, or any other places you can think of. where does all this energy come An energy source is"renewable" when supplies of it never run out and"non-renewable"when one day they will run out. Which energy sources on your list are renewable and which are non-renewable? Pre-reading I Have you ever seen a greenhouse? A greenhouse is made of glass and is used for growing plants, especially during cold weather. 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 2 In the atmosphere surrounding the earth there are gases called "greenhouse gases". What do you think greenhouse gases do? Look at the picture above and explain it to your partner. 25
Reading THE EARTH IS BECOMING WARMER-BUT DOES IT MATTER? During the 20th century the temperature of the earth rose about one degree Fahrenheit That probably does not seem much to you or me, but it is a rapid increase when compared to other natural changes. So how has this come about and does it matter? Earth Care's Sophie Armstrong explores these questions s There is no doubt that the earth is becoming We know that the levels of carbon dioxide warmer(see Graph I)and that it is human activity have increased greatly over the last 100 to 150 that has caused this global warming rather than a years. It was a scientist called Charles Keeling, random but natural phenomenon who made accurate measurements of the amount of carbon dioxide in the atmosphere from 1957 Graph I: Temperature difference from long-term average. to 1997. He found that between these years the 8A2000 carbon dioxide in the atmosphere went up from around 3 15 parts to around 370 parts per million (see Graph 2). All scientists accept this data. They also agree that it is the burning of more and more fossil YEARS AD fuels that has resulted in this increase in carbon INO IXN) In 1930) 199) 10) NN) 30 dioxide. So how high will the temperature All scientists subscribe to the view that the increase go? Dr Janice Foster says that over the increase in the earth's temperature is due to the next 100 years the amount of warming could be 20 burning of fossil fuels like coal, natural gas and as low as I to 1. 5 degrees Celsius, but it could be oil to produce energy. Some byproducts of this as high as 5 degrees process are called"greenhouse gases. the most Graph 2: Carbon dioxide content in the atmosphere important one of which is carbon dioxide. Dr 1957-1997 Janice Foster explains:"There is a natural 2s phenomenon that scientists call the ' greenhouse effect. This is when small amounts of gases in the atmosphere, like carbon dioxide, methane and water vapour, trap heat from the sun and therefore warm the earth. Without the greenhouse effect YEARS AD o the earth would be about thirty-three degrees Celsius cooler than it is. So, we need those gases However the attitudes of scientists towards The problem begins when we add huge this rise are completely different. On the one quantities of extra carbon dioxide into the hand, Dr Foster thinks that the trend which atmosphere. It means that more heat energy increases the temperature by 5 degrees would be 35 tends to be trapped in the atmosphere causing a catastrophe, She says, "We can't predict the the global temperature to go up climate well enough to know what to expect, but 26
it could be very serious Others who agree with is actually a positive thing. It will make plants her think there may be a rise of several metres in grow quicker; crops will produce more; it will the sea level, or predict severe storms, floods, encourage a greater range of animals-all of droughts, famines, the spread of diseases and the which will make life for human beings better disappearance of species. On the other hand, there Greenhouse gases continue to build up in the are those, like George Hambley, who are atmosphere. Even if we start reducing the amount opposed to this view and believe that we should of carbon dioxide and other greenhouse gases not worry about high levels of carbon dioxide in the climate is going to keep on warming for the air. They predict that any warming will be decades or centuries. No one knows the effects 45 mild with few bad environmental consequences. of global warming. Does that mean we should In fact, Hambley states, "More carbon dioxide do nothing? Or, are the risks too great? Comprehending 1 Glance quickly at the magazine article and answer the questions Who wrote the magazine article? What is the name of the magazine? 2 What are the names of the three scientists mentioned in the article? 3 What do they think about global warming? Do they agree with one another? 4 what are the two graphs about? 5 What is the main topic of the article? 2 Read the article carefully Are these statements true or false? Tick the correct boxes. For each false statement write a true one True False The temperature in the last century did not seem to increase much 2 Everyone believes that global warming is caused by the activities of humans 3 Janice Foster believes that she can measure the future global rise in temperature 4 The rise in carbon dioxide is causing a steady increase in global warming 5 George Hambley believes that global warming will do good rather than harm to the earth 6 It is clear what the effects of global warming will be 3 Now you are going to discuss the statement: We should do nothing about global warming. Follow these instructions I 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 students discuss why they agree with the statement: Group B students discuss why they disagree 3 Groups A and B get together. They tell each other the reasons for agreeing or disagreeing with the statement 27
it-t cobi warming Learning about Language Discovering useful words and expressions 1 Find the words in the text that have these two meanings. Take notice of the meaning used in the reading passage, write the words and mark their usage in the chart Possible meanings Word Which used I n a general tendency in the way a situation is changin 2 to start doing something that everyone copies I v. to make something(especially something bad)increase 2 n a substance that can be burned to make heat or energy II the physical or mental condition of someone 2 to formally say or write some information or an opinion I w to use time, energy, goods, etc 2 v.(formal) to eat or drink something I w. to look quickly at someone or something 2 I. to read something very quickly 2 Go over the new words and phrases in the previous sections. Then complete each sentence with one of those new words or phrases I Charles Keeling collected on the carbon dioxide content in the atmosphere over a forty-year period. He found that the amount of carbon dioxide increasing during that time 2 Although we are burning coal in huge every year, we won t of it for centuries s If the amount of greenhouse gases continues to we could be facing a global Many scientists believe that global warming has through the burning of fossil fuels of a rising sea level would be widespread flooding. On the whole the warming of the earth is a that causes great concen shows temperature changes during the 20th century s One hectare of forest can absorb 23 tons of carbon dioxide veal. o The washing machine uses too much energy. but we buy a more economical one. it would still use too much water loThe car accident on the main road yesterday one drivers death 28
nit clobal warming Discovering use/ul structures cOmpare the two sentences below. the second sentence is from the reading passage. Translate them into Chinese and then discuss any difference in meaning and form. Can you explain why "it"is used in the second sentence? Human activity has caused this global warming. It is huuman activity that has caused this global warming In the article there are two more sentences in which"it"is used for emphasis. Find them and then write them down 2 Rewrite each sentence with It is. that/who.. to give more emphasis to the underlined part I Scientists warned that greenhouse gases would warm the earth by trapping heat energy in the atmosphere The greenhouse effect gives the earth's surface the average temperature of 15C s Much of the energy used to light and heat our homes comes from fossil fuels 4 The developed countries consume the most energy in the world Carbon dioxide has the tendency to stay in the atmosphere for centuries while other greenhouse gases stay in the atmosphere only for a day or less 6 Low-lying countries feel their very existence is in danger from rising sea levels Environmentalists have tried to stop the earths temperature rising s Scientists want to find out about future climate changes and their effects on our environment o In the years ahead, the level of the sea could rise by several metres because of global warming 10 In the future outer space might provide us with new energy sources 3 Choose a topic you like(eg global warming, wildlife protection, music, film, etc) for this activity. Work in groups and try to tell the information you know about the topic using emphatic"it EXAMPLE: It was during the 20th century that the temperature of the earth went up about one degree Fahrenheit It is Charles Keeling who made accurate measurements of the amount of carbon dioxide in the atmosphere