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
2010-07-14
40
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 3℃ 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 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 inenia (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.
The article was written to explain______.
选项
A、the greenhouse effect
B、the solar effects on the earth
C、the greenhouse effect
D、the causes affecting weather
答案
D
解析
通过全文的阅读我们可以得知,本文的写作目的是为了揭示天气变化的原因。
转载请注明原文地址:https://kaotiyun.com/show/bz7K777K
0
大学英语六级
相关试题推荐
Thereweretwowidelydivergentinfluencesontheearlydevelopmentofstatisticalmethods.Statisticshadamotherwhowasdedi
TheEnglish【B1】______settlementsinNorthAmericabeganinthe17thcenturywhenWesternEuropewas【B2】______greatchanges
A、Talkingaboutifthewomanwaitedinline.B、Exchangingthetelephonenumbers.C、Sayinghellotoeachother.D、Talkingaboutt
ThestudyfoundthatcigarettesmokingamongAmerican【36】______droppedduringthepastyear.Thedropcontinuesageneraldecre
A、Stealingmoney.B、Misuseofthecompanycar.C、Beinglate.D、Misuseofworktime.A
AIDS(AcquiredImmuneDeficiencySyndrome)isafataldiseasethatdestroystheimmunesystem.MorethanfouroutoffiveAIDSc
EasterEasteristhemostimportantfestivalintheChristiancalendar.ItisthecommemorationofJesus’deathandhisrisi
A、Howtohandlespiders.B、SpidersintheUnitedStates.C、People’sfearofspiders.D、Aspecialkindofspider.B
Technologyisatwo-edgedsword.Rarelyisthisasclearasitisintherealmofhealthcare.Technologyallowsdoctorstotest
CharlieBellbecamechiefexecutiveofMcDonald’sinApril.Withinamonthdoctorstoldhimthathehadcolorectalcancer.After
随机试题
原发性糖尿病可分为()、()、()。
进一步检查应做患者行蝶鞍区肿瘤切除术后第二天出现昏迷,不可能的原因是
某企业进行改扩建工程,投资10万元,预计改扩建后,生产能力及产品质量将有所提高,每年增加收入5万元,其中每年节约材料费1万元,节约人工费2万元。项目每年的运营成本为3万元,项目寿命期8年,基准折现率为10%。则该项目的费用效率为()。
投保人对财产拥有的()权具有保险利益
证券公司向客户融资,可以使用()。Ⅰ.自有资金Ⅱ.客户资金账户内存放期达到规定时间的资金Ⅲ.公司贷款所得Ⅳ.客户信用交易担保资金账户内的资金
每位教师在实际教学中必须充分发挥主观能动性,培养提高自己的(),结合实际情况,以合适新颖的方式来应对音乐教学中的突发事件。
关于我国的岛屿,下列说法不正确的是()。
稳健的货币政策要松紧适度。下列不属于货币政策工具范畴的是()。
A.ParentsusuallyhelpthemB.Thekidsaregoingtrick-or-treatingC.butIdon’tknowhowitiscelebratedD.Ifyougo,take
"I’mnotgoingtobuythatbook.""______.It’stooexpensive."
最新回复
(
0
)