2. 外语
  3. This passage is excerpted from material published in 1997. Scientists have been puzzled by the seeming disparity between models

This passage is excerpted from material published in 1997. Scientists have been puzzled by the seeming disparity between models

admin2019-11-17  83
问题 This passage is excerpted from material published in 1997.
Scientists have been puzzled by the seeming disparity between models of global warming based on greenhouse gas emissions and actual climatological data. In short, the world is not warming up as much as these models have predicted. In the early 1990s, Pat Michaels sought to explain this disparity, suggesting that sulfate emissions in industrial areas had a cooling effect, thus temporarily retarding global warming. Michaels later came to doubt this idea, however, pointing out that since most sulfate is emitted in the Northern Hemisphere, its cooling influence should be largely limited to that hemisphere. Yet, since 1987, warming in the Southern Hemisphere, which had been relatively intense, has virtually ceased, while warming in the north has accelerated. Thus, Michaels not only doubted the idea of sulfate cooling, but came to feel that global warming models themselves may be flawed.
Ben Santer disagrees. Santer contends that, in general, global warming occurs more slowly in the south because this hemisphere is dominated by oceans, which warm more slowly than the landmasses that dominate the Northern Hemisphere. But, according to Santer, the situation remains complicated by sulfate cooling, which peaked in the north in the mid-twentieth century. It drastically slowed warming in the Northern Hemisphere, and warming in the Southern Hemisphere raced ahead. Since 1987, Santer argues, the greenhouse effect has reasserted itself, and the north has taken the lead. Thus, Santer disputes Michaels’s claim that model predictions and observed data differ fundamentally.
According to the passage, Santer asserts which of the following about global warming?
选项 A、It will become a more serious problem in the Southern Hemisphere than in the Northern Hemisphere in spite of the cooling influence of oceans in the south.
B、It is unlikely to be a serious problem in the future because of the pervasive effect of sulfate cooling.
C、It will proceed at the same general rate in the Northern and Southern Hemispheres once the temporary influence of sulfate cooling comes to an end.
D、Until the late 1980s, it was moderated in the Northern Hemisphere by the effect of sulfate cooling.
E、Largely because of the cooling influence of oceans, it has had no discernible impact on the Southern Hemisphere.
答案D
解析 Supporting idea
The second paragraph of the passage discusses Santer’s take on global warming. He is concerned with the effect of oceans and of sulfate cooling on this process, and he argues that the rate of warming in the Southern and Northern Hemispheres has been differently affected by each of these. In general, oceans slow warming in the south, while sulfate cooling temporarily slowed warming in the north until the late 1980s.
A According to the passage, Santer has argued that since 1987 the Northern Hemisphere has warmed more significantly than the Southern Hemisphere.
B Santer maintains that sulfate cooling complicates our attempts to understand global warming. He notes, however, that sulfate cooling peaked in the Northern Hemisphere in the mid-1900s, and that that hemisphere’s warming has increased considerably. So sulfate cooling’s effect is not pervasive and has not mitigated the medium-and long-term problem of global warming.
C Santer argues that, in the absence of sulfate cooling, global warming would occur more slowly in the Southern Hemisphere due to the greater ocean coverage there.
D Correct. Santer says that sulfate cooling slowed warming in the Northern Hemisphere, but that in 1987, the influence of sulfate cooling was no longer significant.
E Santer maintains that global warming happens more slowly in the Southern Hemisphere due to the greater ocean coverage there, not that it has no discerrible impact there.
The correct answer is D.
转载请注明原文地址:https://jikaoti.com/ti/fydYFFFM
本试题收录于： GMAT VERBAL题库GMAT分类
0

GMAT VERBAL

GMAT

相关试题推荐
随机试题
最新回复(0)