The National Academy of Sciences claimed recently that people should caution rather than panic about the greenhouse effect. It is said that the greenhouse effect will result in global warming, which will elevate the earth's temperature by 3～9 degrees Fahrenheit. The greenhouse effect results when carbon dioxide (CO2) and certain other gases in the atmosphere allow the sun's ultraviolet rays to penetrate and warm the earth, but then absorb the infrared energy the earth radiates back into space—much as glass in a greenhouse does—forming a kind of "thermal blanket" around the planet. The greenhouse effect will mean much more than hotter summers and milder winters. It may alter rainfall, affect crop yields and eventually—as glaciers begin to melt—raise the level of the seas. It had long been reported that the earth's temperature would rise, melting the icecaps, raising the seas, flooding the land. Half of Long Island would be under water. Midwest would become a desert. However, the findings of latest studies have indicated that the earth might not undergo warmer temperatures and rather it may experience colder weather. Due to the variable behavior of the sun, the earth may be confronted with another Ice Age. In the past, concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet. But the weather experts are now paying more attention to West Antarctic, which may be affected by only a few degrees of warming: in other words, by a warming on the scale that will possibly take place in the next fifty years from the burning of fuels.A. [■] Satellite pictures show that large areas of Antarctic ice are already disappearing.B. [■] The evidence available suggests that a warming has taken place. This fits the theory that carbon dioxide warms the earth,C. [■] Scientists conclude, therefore, that up to now natural influences on the weather have exceeded those caused by man. The question is: Which natural cause has most effect on the weather?.D.[■] One possibility is the variable behavior of the sun. Astronomers at one research station have studied the hot spots and "cold" spots (that is, the relatively less hot spots) on the sun. As the sun rotates, every 27.5 days, it presents hotter or "colder" faces to the earth, and different aspects to different parts of the earth. This seems to have a considerable effect on the distribution of the earth's atmospheric pressure, and consequently on wind circulation. The sun is also variable over a long term: its heat output goes up and down in cycles, the latest trend being downward. Scientists are now finding mutual relations between models of solar-weather interactions and the actual climate over many thousands of years, including the last Ice Age. The problem is that the models are predicting that the world should be entering a new Ice Age and it is not, One way of solving this theoretical difficulty is to assume a delay of thousands of years while the solar effects overcome the inertia of the earth's climate. If this is right, the warming effect of carbon dioxide might thus be serving as a useful counterbalance to the sun's diminishing heat. In addition to the variable behavior of the sun, new research has also demonstrated that global warming will probably lead in the end to a period of much colder weather, at least in Europe. Scientists base their theory on what happened the last time the world warmed up, 8300 years ago. They have discovered that when the ice melted from the northern polar ice cap it became trapped in an enormous lake in northern Canada. As more ice melted this lake suddenly burst open, releasing millions of tons of freezing fresh water into the North Atlantic. This flood of water was so large that it prevented the normal flow of water in the Atlantic, which takes warm water from the tropics north to Europe and thus temperatures in Europe dropped by between three and eight degrees Celsius over the next two hundred years. Scientists believe that a similar process could occur in the next century if the Greenland Ice Sheet starts to melt.
单选题
The word elevate in Paragraph 1 is closest in meaning to______. A. modify B. raise C. defend D. collect
【正确答案】
B
【答案解析】[解析] 本题为词汇题，主要考查考生根据上下文对单词elevate的理解。根据elevate所在句“It is said that greenhouse effect will result in global warming，which will elevate the earth's temperature by 3-9 degrees…(温室效应会导致全球变暖，使地球温度提高3～9度)”的意思，可以推断elevate是“提高”的意思，因此选择B。而其他选项A(改变)、C(防御)、D(收集)均不符合题意。
单选题
In Paragraph 1, the author mentions all of the following results of the greenhouse effect EXCEPT______. A. Midwest would become a desert B. half of Long Island would be under water C. the earth's temperature would rise D. Arizona would turn into a rain forest
单选题
In Paragraph 1, the author explains the concept of the greenhouse effect by______. A. identifying different causes of global warming B. comparing the scientific concept to a familiar human experience C. arguing that the greenhouse effect results in global warming D. describing how the greenhouse effect is formed
单选题
According to the passage, what natural phenomenon is most likely to lead to cold weather in the future? A. The flood of water in northern Canada. B. The variable behavior of the sun. C. The warming of carbon dioxide. D. The circulation of the wind.
【正确答案】
B
【答案解析】[解析] 本题为事实信息题，考查考生是否具备抓住文章中阐明的信息并排除干扰项的能力。题目问：根据文章的内容，什么自然现象最可能导致未来的寒冷天气?根据第二段的首句“Due to the variable behavior of the sun，the earth may be confronted with another Ice Age (南于太阳反复不定的活动，地球可能会面临另一个冰川时代)”，可推断出选项B为正确答案。
单选题
According to the passage, which part of the earth did scientists focus their attention on when researching past man-made warming of the earth? A. West Arctic. B. East Antarctic. C. West Antarctic. D. The Arctic.
【正确答案】
D
【答案解析】[解析] 本题为事实信息题，考查考生抓住文章中阐明的信息并排除干扰项的能力。题目问：根据文章的阐述，关于地球人为变暖这一问题，科学家以前集中关注地球的哪一部分?根据第二段第二句“In the past，concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet (过去，科学家们把对地球人为变暖这一关注的重点放在北极，因为南极更冷且冰层更厚)可知，选项D为正确答案。
单选题
The word this in Paragraph 3 refers to______. A. the effect of the hot and cold aspects by the sun on the earth B. the distribution of the earth's atmospheric pressure C. the solar-weather interactions D. the warming effect of carbon dioxide
【正确答案】
A
【答案解析】[解析] 本题为指代关系题，考查考生能否认定代词与篇章中其他词语的连接指代关系。题目问：文中的this指代的是什么?第三段第三句说“As the sun rotates，every 27.5 days，it presents hotter or 'colder' faces to the earth, and different aspects to different parts of the earth”，即“当太阳运转时，每隔27.5天，它就交替地将其较热或‘较冷’的一面朝向地球，并且南于每个朝向的方位不同也会对地球的不同地区产生不同的影响”。显然，“this”指代的就是前面的整个句子，即“‘这种情况’在很大程度上影响到地球上气压的分布，气流的循环也因此受到影响”，因此选择A。
单选题
The word diminishing in Paragraph 3 is closest in meaning to______. A. developing B. allowing C. decreasing D. suspending
单选题
It can be inferred from Paragraph 3 that the greenhouse effect may be beneficial in______. A. preventing the earth from getting hotter B. delaying the coming of the next Ice Age C. making up for the loss of the sun's heat as indicated D. slowing down the melting of ice in the polar areas
【正确答案】
C
【答案解析】[解析] 本题为推断题，考查考生能否对文章中没有明确阐述但暗示了的信息进行推断。题目问：从第三段可以推论出温室效应的好处是什么?最后一句指出：“If this is right，the warming effect of carbon dioxide might thus be serving as a useful counterbalance to the sun's diminishing heat.”因此，选项C为正确答案。
单选题
In Paragraph 3, it is assumed that the possible reason that the earth is not experiencing an Ice Age as it should be is that A. the sun's heat output does not follow certain regulations B. no rule can be drawn from the sun's rotation C. there is no way to model the sun's rotation D. It takes time for the sun to reduce the inertia of the earth's climate
【正确答案】
D
【答案解析】[解析] 本题为事实信息题，主要考查考生抓住文章中阐明的信息并排除干扰项的能力。题目问：根据第三段的内容，地球本应经历冰川时代但却没有经历，原因是什么?根据第三段倒数第二句“One way of solving this theoretical difficulty is to assume a delay of thousands of years while the solar effects overcome the inertia of the earth's climate”，即“解决这类理论难题的一种方法是：当太阳的作用克服了地球气候的惯性作用时，似定将时间推迟几千年”，所以选项D为正确答案。
单选题
Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. A. The flow of water in the Atlantic takes warm water from the tropics north to Europe, which resulted in the drop in temperature in Europe in the future. B. The temperature in the Europe dropped by between three and eight degrees Celsius over the next two hundred years due to the flood of water. C. Huge amounts of water from northern Canada flooded Europe two hundred years ago, which caused the temperature in Europe to have dropped by between three and eight degrees Celsius. D. The flood of water caused by the ice melting from the northern polar ice cap resulted in the drop in temperature in Europe over the next two hundred years.
单选题
Look at the four squares [■] that indicate where the following sentence could be added to the passage. However, most of the fuel is burnt in the northern hemisphere, where temperatures seem to be falling. Where would the sentence best fit? A. Square Ａ. B. Square Ｂ. C. Square Ｃ. D. Square Ｄ.
问答题Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. The latest research demonstrates that the earth may experience colder weather in the future.
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Answer Choices A. The ice melting from the northern polar ice cap 8300 years ago leads to the release of millions of tons of water from a lake into the North Atlantic. B. The behavior of the sun has more effect on the weather of the earth than greenhouse effect caused by man's burning of fuels. C. Since the sun's heat output is going down at present, scientists claim that the earth is likely to experience cold temperature thousands of years in the future. D. Greenhouse effect might not do harm to humans and rather may bring benefits to human beings. E. It is pointed out that humans' burning of fuels will eventually cause the ice sheet in the polar areas to melt and thus flood the whole earth. F. The facts of the last Ice Age show that the earth may undergo much colder weather in the next century if the Greenland Ice Sheet begins to melt.
【正确答案】
B. The behavior of the sun has more effect on the weather of the earth than greenhouse effect caused by man's burning of fuels.
C. Since the sun's heat output is going down at present, scientists claim that the earth is likely to experience cold temperature thousands of years in the future.
F. The facts of the last Ice Age show that the earth may undergo much colder weather in the next century if the Greenland Ice Sheet begins to melt.