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 su
In the atmosphere, carbon dioxide acts rather like a one-way mirror -- the glass in the roof of a greenhouse which allows the su
admin
2010-07-06
12
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~C 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 metres 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 relation 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 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.
Although the fuel consumption is greater in the northern hemisphere, temperatures there seem to be falling. This is ______.
选项
A、mainly because the levels of carbon dioxide are rising
B、possibly because the ice caps in the poles are melting
C、exclusively due to the effect of the inertia of the earth’s climate
D、partly due to variations in the output of solar energy
答案
D
解析
根据文章第六段第一句(主题句)和本段最后一句(结论句),可知 D是正确答案。
转载请注明原文地址:https://jikaoti.com/ti/jLisFFFM
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
Ialwayseatbreakfast,andsuggestthatyoudotoo.Weallneedfoodinthemorningtosupplyourselves【C1】________sourcesofg
Ialwayseatbreakfast,andsuggestthatyoudotoo.Weallneedfoodinthemorningtosupplyourselves【C1】________sourcesofg
WhydoesDr.Johnsonsuggestbuildingagreenhousenearapowerstation?Whichofthefollowingcanbeusedasfertilizer?
EFirstofall,we’dliketoknowsomethingaboutyou,soI’mgoingtoasksomequestionsaboutyourselves.EWhatdoyouusually
ThedailycirculationoftheDailyMirrorandtheDailyExpressis______.
ThedailycirculationoftheDailyMirrorandtheDailyExpressis______.
Whilefashionisthoughtofusuallyinrelationtoclothing,itisimportanttorealizethatitcoversamuchwiderdomain.Iti
Researcherssaidthatchildrendonotnecessarilydevelophealthybonesinareportthatstresses______consumptionofcalcium-
Twofactorsweighheavilyagainsttheeffectivenessofscientificresearchinindustry.Oneisthegeneralatmosphereofsecrecy
Twofactorsweighheavilyagainsttheeffectivenessofscientificresearchinindustry.Oneisthegeneralatmosphereofsecrecy
随机试题
根据所给资料,下列说法正确的是:
患者,女,20岁。左乳外上方圆形肿块,质地坚韧,表面光滑,活动度较好,边界清,无压痛。应首先考虑的诊断是
紫癜与充血性皮疹的主要区别是
[1995年第036题]我国已知的四合院建筑最早实例是:
下列关于财政的主要职责的说法,错误的是()。
局部突出屋面的楼梯间、电梯机房、水箱间、烟囱等在城市一般建设地区()。
张老师上课幽默风趣,但是对学生要求很严格。有一次一个学生在黑板上演示题目时做不出来,张老师一怒之下便扇了这个学生一耳光,并用很粗俗的话骂他,则下列说法正确的是()。
自行车:传送带
AVerySlowRideThesurfaceoftheearthmayseemverystabletoyou.Butyoumightbeamazedifyouknewsomeofthething
______thesetrainstoBeijingwouldyouliketotake?
最新回复
(
0
)