首页
登录
职称英语
Ozone in the stratosphere blocks deadly ultraviolet rays from the sun, but chlor
Ozone in the stratosphere blocks deadly ultraviolet rays from the sun, but chlor
游客
2025-02-25
7
管理
问题
Ozone in the stratosphere blocks deadly ultraviolet rays from the sun, but chlorofluorocarbons (CFCs) in aerosols and other products have thinned this protective layer. Evidence of this is the ozone hole that forms over the South Pole every Antarctic spring as temperatures drop below -78°C, the temperature at which ozone depletion occurs. Measurements of the ozone hole taken at various times this spring show that, compared with the same times the previous year, its area diminished by four million square kilometers. Nevertheless, scientists have not concluded that the ozone layer is recovering.
Which of the following would, if true, provide the strongest reason for the scientists’ reaction to the measurements?
选项
A、The ozone hole has steadily grown in size every year for the past decade except this year.
B、The length of time that the ozone hole persists fluctuates from year to year.
C、As a result of international treaties, CFCs have been completely banned for several years.
D、Weather patterns allowed unusual amounts of warm air to mix into the polar regions this year.
E、Human-made CFCs retain their ability to destroy ozone molecules for seventy-five to one hundred years.
答案
D
解析
This question requires us to identify which of the answer choices would provide the strongest reason
to support the scientists’ skepticism about whether the ozone layer is recovering.
This skepticism exists despite the fact that measurements of the ozone hole taken at various times during the Antarctic spring have shown that the hole has diminished significantly from its size at the same times the previous year.
One major reason to be skeptical would be if there were some factor other than a recovery of the ozone layer that could reasonably account for the diminished size of the hole.
A This does not give much reason to be skeptical that the ozone layer is recovering. Certainly one would not want to be too hasty in declaring a recovery after noting a trend of growth in the ozone hole’s size. Nevertheless, something must account for this year’s divergence from the trend. It seems reasonable to conclude, barring the discovery of some other factor that would explain the change, that a recovery in the ozone layer could be a factor in this year’s divergence.
B Each of the measurements was smaller than at the same time in the previous year. This fact would seem to indicate that fluctuations in the length of time the ozone hole persists do not justify the scientists’ skepticism.
C The fact that CFCs—which led to the thinning of the ozone layer—have been banned counts against the scientists’ skepticism rather than supports it.
D Correct. The hole forms when the temperature drops below -78°C during the Antarctic spring. If much of the area where the hole appears was significantly warmer than the previous year—perhaps above -78°C—there exists a reason other than a recovery in the ozone layer that explains the smaller size of this year’s hole in the ozone. This would support the scientists’ skepticism.
E Even if CFCs retain their ability to destroy ozone molecules for many decades, something must account for the decrease in the size of the hole. Nothing in the passage indicates whether the amount of CFCs in the atmosphere has been increasing or decreasing. If it has been decreasing for a long time, then this fact is compatible with a belief that the ozone layer is recovering.
The correct answer is D.
转载请注明原文地址:https://tihaiku.com/zcyy/3971592.html
相关试题推荐
Ozoneinthestratosphereblocksdeadlyultravioletraysfromthesun,butchlor
Whileridingabicycle,apersontraveled5blocksin2minutes.Atthisrate,h
A、LowtemperaturesB、UltravioletradiationC、AcidicenvironmentsD、Hightemperat
Theskinofthepoisondartfrogcontainsdeadlypoisonscalledbatrachotoxins.
随机试题
Whyisthenightflightmoreharmful?A、Becauseitisnotsaferthandaytimeflig
Manystudentsfindtheexperienceofattendinguniversitylecturestobeac
设备监理实施细则的主要内容中不包括()。A.各个专业工程的特点和设备专业监理
进程PA不断地向管道写数据,进程PB从管道中读数据并加工处理,如下图所示。如果采
某公司只生产和销售一种产品,销售价格为75元/件,全年产销量为400万件,固定成
某省的生物中考满分为100分,某同学得了55分,最终成绩单上给出的成绩是“B”。
关于尿蛋白干化学法测定,正确的是( )。A.尿液pH3~9之问,测定最合适
正确贮存的情况下,硫酸庆大霉素注射剂的外观性状为A:淡红色的澄明液体 B:无色
“以退为进”形象说明了以下哪种问题解决的策略() A.算法B.手段一目的分析
请认真阅读下文,并按要求作答。 问题(一):如指导中年段小学生学习
最新回复
(
0
)