综合类相同项单选集试卷（综合类）_16.docVIP

试卷第 PAGE 1 页共 NUMPAGES 1 页 综合类相同项单选集试卷（综合类） 姓名:_____________ 年级:____________ 学号:______________ 题型 选择题 填空题 解答题 判断题 计算题 附加题 总分 得分 评卷人 得分 1、A Sunshade for the Planet Even with the best will in the world, reducing our carbon emissions is not going to prevent global warming. It has become clear that even if we take the most strong measures to control emissions, the uncertainties in our climate models still leave open the possibility of extreme warming and rises in sea level. At the same time, resistance by governments and special interest groups makes it quite possible that the actions suggested by climate scientists might not be implemented soon enough. Fortunately, if the worst comes to the worst, scientists still have a few tricks up their sleeves. For the most part they have strongly resisted discussing these options for fear of inviting a sense of complacency that might thwart efforts to tackle the root of the problem. Until now, that is. A growing number of researchers are taking a fresh look at large-scale “geoengineering” projects that might be used to counteract global warming. “I use the analogy of methadone,” says Stephen Schneider, a climate researcher at Stanford University in California who was among the first to draw attention to global warming. “If you have a heroin addict, the correct treatment is hospitalization, and a long rehab. But if they absolutely refuse, methadone is better than heroin.” Basically the idea is to apply “sunscreen” to the whole planet. One astronomer has come up with a radical plan to cool Earth; launch trillions of feather-light discs into space, where they would form a vast cloud that would block the sun’s rays. It’s controversial, but recent studies suggest there are ways to deflect just enough of the sunlight reaching the Earth’s surface to counteract the warming produced by the greenhouse effect. Global climate models show that blocking just 1.8 percent of the incident energy in the sun’s rays would cancel ou