首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
In the atmosphere, carbon dioxide acts rather like a one-way mirror—the glass in the roof of a greenhouse which allows the sun’s
In the atmosphere, carbon dioxide acts rather like a one-way mirror—the glass in the roof of a greenhouse which allows the sun’s
admin
2017-02-01
48
问题
In the atmosphere, carbon dioxide acts rather like a one-way mirror—the glass in the roof of a greenhouse which allows the sun’s rays to enter but prevents the heat from escaping.
According to a weather expert’s prediction, the atmosphere will be 31 warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate. If this warming up took place, the ice caps in the poles would begin to melt, thus raising sea level several meters and severely flooding coastal cities. Also, the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere, possibly resulting in an alteration of the earth’s chief food-growing zones. 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.
Satellite pictures show that large areas of Antarctic ice are already disappearing. The evidence available suggests that a warming has taken place. This fits the theory that carbon dioxide warms the earth.
However, most of the fuel is burnt in the northern hemisphere, where temperatures seem to be falling. 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?
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(惯性)of the earth’s climate. If this is right, the warming effect of carbon dioxide might thus be serving as a useful counter-balance to the sun’s diminishing heat.
It can be concluded that a concentration of carbon dioxide in the atmosphere would _____.
选项
A、prevent the sun’s rays from reaching the earth’s surface
B、mean a warming up in the Arctic
C、cause great climate changes in the northern hemisphere
D、raise the temperature of the earth’s surface
答案
D
解析
从第1段对二氧化碳造成温室效应的原理描述,即可判断本题答案为D项。根据第4段第3句“这种情况符合二氧化碳使地球变暖的理论”也可判断D项符合题意。此外,本题也可以根据有关温室效应的常识求解。
转载请注明原文地址:https://kaotiyun.com/show/uEU7777K
0
大学英语六级
相关试题推荐
A、FlytoClevelanddirectly.B、TakeaconnectingflightatSeattle.C、BuytheticketatSeattle.D、Buyadomesticairlineticket
Afterdecadesofdecline,theshareofmotherswhostayhomewiththeirchildrenhas【C1】______risenoverthelastseveralyears,
Afterdecadesofdecline,theshareofmotherswhostayhomewiththeirchildrenhas【C1】______risenoverthelastseveralyears,
A、Itallowsonetoshowhispersonalinformation.B、Itoffersonlythechildren’spersonalinformation.C、Itisagainstparents’
A、Ithadmanymorepagesthannewspapers.B、Itwasgivenawayforfree.C、Itdealtwithissuesratherthanevents.D、Itwasmore
A、Becausetakingthesubwayisfasterthoughlessdirect.B、Becausetakingthesubwayislessexpensive.C、Becausetakingthebu
A、Toobservepeople’sattitudetowardsstrangers.B、Toseehowpeoplegetalongwiththeirfriends.C、Totestpeople’sbehavior
A、Theyarelikeraysofthesunandthesouthernlights.B、Theyrepresentthebeautifulseasonofspring.C、Thereisonlyashor
A、AdocumentarycalledParkLife.B、AdramadirectedbyKeithEdwards.C、ATVseriescalledNorthWhale.D、AmoviestarredClint
随机试题
由于人为活动对自然环境的改变导致人体出现非正常疾病和有害的生理过程,使人类生理素质和健康水平下降的现象叫做()。
窦房结能成为心脏正常起搏点的原因是()
A.剖宫产术B.产钳助产术C.缩宫素点滴D.手转儿头E.人工破膜初产妇,孕38周,宫口开大8+cm,先露头S+1,宫缩时达S+2,ROT位,胎心正常,产妇开始向下屏气用力
下列关于有限责任公司设立的说法中正确的是()。
调整中央银行基准利率是中国人民银行采用的主要利率工具之一,以下哪一项不属于中央银行基准利率?()
从《礼记》中抽出的是()。
下列植物中,不属于国家一级保护植物的是()。
2016年9月21日,国务院总理李克强在纽约联合国总部出席第71届联合国大会以“可持续发展目标:共同努力改造我们的世界”为主题的一般性辩论并发表题为《携手建设和平稳定可持续发展的世界》的重要讲话。下列有关其讲话内容不正确的是()。
假设随机变量X1,X2,…,X2n独立同分布,且E(Xi)=D(Xi)=1(1≤i≤2n),如果Yn=则当常数C=________时,根据独立同分布中心极限定理,当n充分大时,Yn近似服从标准正态分布。
Scientistsusedtothinkthatmenaredifferentfromanimalsbecausetheycanthinkandlearn.Theynowknowhowanimalscanl
最新回复
(
0
)