新世纪英语专业综合教程unit8课后答案lecturenotes解析

Unit 8 Focus on Global WarmingSection One Pre-reading ActivitiesCultural information1. Global warmingGlobal warming is the increase in the average temperature of Earth‘s near-surface air and oceans since the mid-20th century and its projected continuation. Most of the 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 amount 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 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, and practical actions to tackle the problem.2.What’s the author’s purpose of writing?To raise people’s consciousness of the potential dangers of global warming, and to suggest some actions to combat it.II Structural analysis2. Figure out the sub-ideas in the second part.1) the causes of the rising concentration of greenhouse gases in the atmosphere (Paragraphs 3 and4)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 WarmingJohn Weier1Twenty-five years ago if you made a trip to the local library and perused the periodical section for articles on global warming, you’d probably have come up with only a few abstracts from hardcore science journals or maybe a blurb in some esoteric geopolitical magazine. As an Internet search on global warming now attests, the subject has become as rooted in our public consciousness as Madonna2 or microwave cooking.12Perhaps all this attention is deserved. With the possible exception of another world war, giant asteroid, or an incurable plague, global warming may be the single largest threat to our planet.2For 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.3If we don’t curb our greenhouse gas emissions, then low-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 Planet3What has worried many people now is that over the past 250 years humans have been artificially raising 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 methane-belching cattle.Nitrogen-based fertilizers, which we use on nearly all our crops, release unnatural amounts of nitrogen oxide into the atmosphere.4Once these carbon-based greenhouse gases get into the atmosphere, they stay there for decades or longer. According to the Intergovernmental Panel 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 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 Earth’s atmosphere in much the same way that a windshield traps solar energy that enters a car.45Much of the available climate data appear to back these fears.5Temperature 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 over several decades. Worldwide measurements of sea level show a rise of 0.1 to 0.2 meters over the last century. That’s an increase of roughly 1℃every 4,000 years. Readings gathered from glaciers reveal a steady recession of the world’s continental glaciers. Taken together, all of these data suggest that over the last century the planet has experienced the largest increase in surface temperature in 1,000 years.6Not surprisingly, many scientists speculate that such changes in the climate will probably result in hotter days and fewer cool days.6According to the IPCC, land surface areas will increase 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.7As 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. More 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 heatstroke 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 problems.Taking Actions8Fortunately, we can take actions to slow down global warming.8Global 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 deforestation. 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.9We can also do things to mitigate the 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.10But we can’t stop there. We are also advocating policies that will combat global warming over the long term, things like clean cars that run on alternative fuels, environmentally responsible renewable energy technologies, and stopping the clear-cutting of valuable forests.11Clearly, global warming is a huge problem. It will take everyone —governments, industry, communities and individuals working together to make a real difference.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, frequent hurricanes and intense El Ninos.Words and Expressions1. peruse vt. to read through something, especially in order to find the part you are interested ine.g. He opened a newspaper and began to peruse the personal ads.Derivation:perusal n.e.g. a brief perusalHe sent a copy of the report to the governors 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 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 the family’s 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 consciousness?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 she’s 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:unconsciousnessComparison:subconscious a.潜意识的conscience n.良心conscientious a.（指人或行为）认真的，尽责的1. Our ______ mind registers things which our ______ mind is not aware of. (subconscious, conscious)2. My brother is a ______ student. (conscientious)3. My ______ would really trouble me if I wore a fur coat. (conscience)6. deserve vt. to be worthy ofe.g. I’m glad she got the first prize at the English Speech Contest — she thoroughly deserved it.I said some cruel things to him, but he deserved it for the way he treated me.Derivation:deserving a.e.g. The money is only given to the most deserving cases — to the people who need it most.His efforts are certainly deserving of praise.7. threat n. a strong possibility that something very bad will happene.g. With so many new offices being built in the city, a lot of archaeological remains are under threat.Drunken drivers pose a serious threat to other road users.Collocation:be under threat of sth.e.g. She left the country under threat of arrest if she returned.Derivation:threaten v.threatening a.8. with the exception of except, not includinge.g. I think every student, with the exception of Helen, will pass the exam.With the exception of gold, the surfaces of metals are never observed but only their oxides. Collocation:without exceptionhave no exceptionexception to sth.make an exception9. spew vt. to pour out, esp. quickly and violentlye.g. One engine of the plane caught fire and spewed black smoke.He spewed forth what he had recently learned about the true facts.Collocation:spew sth. up: to vomit10. harbinger n. something that indicates or foreshadows what is to comee.g. The crowing of the rooster is a harbinger of dawn.Frost is a harbinger of winter.Collocation:harbinger of sb. / sth.11. curb vt. to stop something that is harmfule.g. This government has made pioneering strides towards curbing air pollution.The only way to curb the spread of the disease is by immunizing the entire population.12. emission n. the act of sending forth; dischargee.g. The Green Party have called for a substantial reduction in the emission of greenhouse gases by the UK.Derivation:emit v.e.g. The alarm emits infra-red rays which are used to detect any intruder.The machine emits a high-pitched sound when you press the button.Activity: DiscussionWhat kind of periodical do you usually peruse? Why do you like that periodical? What thoughts do you come up with after reading that periodical? Share your favorite periodical with your groupSentences1. As Internet search on global warming now attests, the subject has become as rooted in our public consciousness as Madonna or microwave cooking. (Paragraph 1)Paraphrase: An Internet search on global warming proves that the subject has got fixed in people’s mind, just like Madonna or microwave cooking.Translation: 而今因特网上搜索的结果足以证明，全球气候变暖这个话题就像麦当娜和微波炉烹饪一样深入人心。