This passage is excerpted from material published in 1997.Scientists have been

游客2024-01-12  26

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. [br] The passage suggests that, in the early 1990s, Michaels would have been most likely to agree with which of the following statements about the disparity mentioned in the lines 3-4?

选项 A、This disparity is relatively less extreme in the Northern Hemisphere because of sulfate cooling.
B、This disparity is only a short-term phenomenon brought about by sulfate cooling.
C、This disparity is most significant in those parts of the world dominated by oceans.
D、The extent of this disparity is being masked by the temporary effect of sulfate cooling.
E、The disparity confirms that current models of global warming are correct.

答案 B

解析 Inference
The disparity highlighted in this question is between global warming models and actual climate data— that is, that the models predicted warming that has not occurred. In the early 1990s, according to the passage, Michaels tried to explain this disparity by saying that industrial sulfate emissions had a cooling effect that slowed global warming briefly.
A The passage does not indicate that Michaels came to distinguish between the Northern and Southern Hemispheres until he began to doubt his early 1990s explanation for the mentioned disparity.
B Correct. Michaels claimed in the early 1990s that the disparity was temporary, and that it occurred due to the cooling effect of sulfate emissions.
C Santer’s contention, not Michaels’s, is based on the effect of oceans on global warming.
D In the early 1990s, Michaels used the idea of sulfate cooling to explain the observed disparity, not to suggest that the disparity itself was larger than observed.
E In seeking to explain the disparity, Michaels seems to have assumed, in the early 1990s at least, that the models of global warming were correct. But he did not take the disparity as evidence of their correctness.
The correct answer is B.
转载请注明原文地址:https://tihaiku.com/zcyy/3357164.html
最新回复(0)