新世纪英语专业综合教程unit8课后答案lecturenotes解析.docx

1、新世纪英语专业综合教程unit8课后答案lecturenotes解析Unit 8 Focus on Global Warming Section One Pre-reading ActivitiesCultural information1. Global warmingGlobal warming is the increase in the average temperature of Earths near-surface air and oceans since the mid-20th century and its projected continuation. Most of t

2、he observed temperature increase since the middle of the 20th century was caused by increasing concentrations of greenhouse gases, which results from human activity such as fossil fuel burning and deforestation. An increase in global temperature will cause sea levels to rise and will change the amou

3、nt and pattern of precipitation, probably including expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with continuing retreat of glaciers, permafrost and sea ice. Other likely effects include changes in the frequency and intensity of extreme

4、weather events, species extinctions, and changes in agricultural yields. Section Two Global ReadingI Text analysis1.From which perspectives does the text address the issue of global warming? The text addresses the issue from three perspectives the general public concern, its causes and consequences,

5、 and practical actions to tackle the problem.2.Whats the authors purpose of writing?To raise peoples consciousness of the potential dangers of global warming, and to suggestsome actions to combat it.II Structural analysis1. Divide the text into parts by completing the table. ParagraphsMain idea1-2Th

6、e author tells the reason why people are now increasingly concerned about global warming.3-7The author traces the causes of global warming and discusses the consequences of it.8-11The author puts forward some suggestions on what is to be done.2. Figure out the sub-ideas in the second part.1) the cau

7、ses of the rising concentration of greenhouse gases in the atmosphere (Paragraphs 3 and 4)2) the effect of such concentration on climate change (Paragraphs 5 and 6)3) the potential threat of global warming to human health and survival (Paragraph 7)Section Three Detailed ReadingText IFocus on Global

8、WarmingJohn Weier1 Twenty-five years ago if you made a trip to the local library and perused the periodical section for articles on global warming, youd probably have come up with only a few abstracts from hardcore science journals or maybe a blurb in some esoteric geopolitical magazine. As an Inter

9、net search on global warming now attests, the subject has become as rooted in our public consciousness as Madonna2 or microwave cooking.12 Perhaps all this attention is deserved. With the possible exception of another world war, giant asteroid, or an incurable plague, global warming may be the singl

10、e largest threat to our planet.2 For decades human factories and cars have spewed billions of tons of greenhouse gases into the atmosphere, and the climate has begun to show some signs of warming. Many see this as a harbinger of what is to come.3 If we dont curb our greenhouse gas emissions, then lo

11、w-lying nations could be awash in seawater, rain and drought patterns across the world could change, hurricanes could become more frequent, and El Ninos could become more intense. Our Warming Planet3 What has worried many people now is that over the past 250 years humans have been artificially raisi

12、ng the concentration of greenhouse gases in the atmosphere. Our factories, power plants, and cars burn coal and gasoline and spit out a seemingly endless stream of carbon dioxide. We produce millions of pounds of methane by allowing our trash to decompose in landfills and by breeding large herds of

13、methane-belching cattle. Nitrogen-based fertilizers, which we use on nearly all our crops, release unnatural amounts of nitrogen oxide into the atmosphere.4 Once these carbon-based greenhouse gases get into the atmosphere, they stay there for decades or longer. According to the Intergovernmental Pan

14、el on Climate Change (IPCC) since the industrial revolution, carbon dioxide levels have increased 31 percent and methane levels have increased 151 percent. Paleoclimate readings taken from fossil records show that these gases, two of the most abundant greenhouse gases, are at their highest levels in

15、 the past 420,000 years. Many scientists fear that the increased concentrations of greenhouse gases have prevented additional thermal radiation from leaving the Earth. In essence, these gases are trapping excess heat in the Earths atmosphere in much the same way that a windshield traps solar energy

16、that enters a car.45 Much of the available climate data appear to back these fears.5 Temperature data gathered from many different sources all across the globe show that the surface temperature of the Earth, which includes the lower atmosphere and the surface of the ocean, has risen dramatically ove

17、r several decades. Worldwide measurements of sea level show a rise of 0.1 to 0.2 meters over the last century. Thats an increase of roughly 1 every 4,000 years. Readings gathered from glaciers reveal a steady recession of the worlds continental glaciers. Taken together, all of these data suggest tha

18、t over the last century the planet has experienced the largest increase in surface temperature in 1,000 years.6 Not surprisingly, many scientists speculate that such changes in the climate will probably result in hotter days and fewer cool days.6 According to the IPCC, land surface areas will increa

19、se in temperature over the summer months much more than the ocean. The mid-latitude to high-latitude regions in the Northern Hemisphere areas such as the Continental United States, Canada, and Siberia will likely warm the most. These regions could exceed mean global warming by as much as 40 percent.

20、7 As far as human health is concerned, those hit hardest will probably be residents of poorer countries that do not have the funds to fend against changes in climate.7 A slight increase in heat and rain in equatorial regions would likely spark an increase in vector-borne diseases such as malaria. Mo

21、re intense rains and hurricanes could cause more severe flooding and more deaths in coastal regions and along riverbeds. Even a moderate rise in sea level could threaten the coastlines of low-lying islands such as the Maldives. All across the globe, hotter summers could lead to more cases of heatstr

22、oke and deaths among those who are vulnerable, such as older people with heart problems. The warmer temperatures may also lead to higher levels of near-surface ozone from cars and factories, which would likely cause more perilous air quality days and hospital admissions for those with respiratory pr

23、oblems. Taking Actions8 Fortunately, we can take actions to slow down global warming.8 Global warming results primarily from human activities that release heat-trapping gases and particles into the air. The most important causes include the burning of fossil fuels such as coal, gas, and oil, and def

24、orestation. To reduce the emission of heat-trapping gases like carbon dioxide, methane, and nitrous oxides, we can curb our consumption of fossil fuels, use technologies that reduce the amount of emissions wherever possible, and protect the forests in the world.9 We can also do things to mitigate th

25、e impacts of global warming and adapt to those most likely to occur,9 e.g., through careful planning and other strategies that reduce our vulnerability to global warming.10 But we cant stop there. We are also advocating policies that will combat global warming over the long term, things like clean c

26、ars that run on alternative fuels, environmentally responsible renewable energy technologies, and stopping the clear-cutting of valuable forests.11 Clearly, global warming is a huge problem. It will take everyone governments, industry, communities and individuals working together to make a real diff

27、erence. Fortunately you can be part of them. Paragraphs 1-2Questions1. Why have people shown increasing concern about global warming? (Paragraph 2)The answer lies in the second paragraph: it is a harbinger of what is to come the threat to low-lying nations, change of rain and drought patterns, frequ

28、ent hurricanes and intense El Ninos.Words and Expressions1. peruse vt. to read through something, especially in order to find the part you are interested in e.g. He opened a newspaper and began to peruse the personal ads.Derivation:perusal n.e.g. a brief perusal He sent a copy of the report to the g

29、overnors for their perusal.2. periodical n. a publication that appears at fixed intervals, esp. one of a serious kinde.g. She has written for several legal periodicals.Derivation: period n. periodic a. occurring or appearing at (esp. regular) intervals 定期的，周期的periodically ad.3. come up with to think

30、 of an idea, plan, reply, etc.e.g. No one has come up with a convincing explanation of why dinosaurs died out.The scientists are beating their brains trying to come up with a solution to the problem.4. attest vt. / vi. to demonstrate, to declare to be truee.g. The luxurious furnishings attested to t

31、he familys wealth.The perfection of their design is attested by the fact that they have survived for thousands of years.Collocation:attest (to) sth.Derivation: attestation n.5. consciousness n.1) the condition of being awake and understanding what is happeninge.g. When will the patient regain his co

32、nsciousness?The blow caused him to lose consciousness.2) all the ideas, thoughts, feelings, etc. of a person or peoplee.g. Love for freedom runs deep in the national consciousness.This experience helped to change her social consciousness.Collocation:consciousness of sth. / that awareness of sth. / that e.g. Her consciousness that shes different makes her feel uneasy. regain / recover consciousness 恢复意识，恢复知觉 lose consciousness 失去意识，失去知觉Antonym: unconsciousness Comparison:subconscious