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
61
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.
The article was written to explain ______.
选项
A、the greenhouse effect
B、the solar effects on the earth
C、the models of solar-weather interactions
D、the causes affecting weather
答案
D
解析
本文前半篇叙述二氧化碳对地球天气的影响,后半篇则说明太阳发出的热量变化对地球天气的作用。且由于自然原因,地球温度有可能下降。这样,二氧化碳作为地球热量的保护层起到了积极的平衡作用。综上所述,本文的目的是说明影响地球天气的各种因素。
转载请注明原文地址:https://kaotiyun.com/show/aVDd777K
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
Ialwayseatbreakfast,andsuggestthatyoudotoo.Weallneedfoodinthemorningtosupplyourselves【C1】________sourcesofg
Ialwayseatbreakfast,andsuggestthatyoudotoo.Weallneedfoodinthemorningtosupplyourselves【C1】________sourcesofg
ThepagesoftheHarvardBusinessReviewarenotusuallypopulatedbynovelists.ButJosephFinderisjustsuchararity.Recent
ThepagesoftheHarvardBusinessReviewarenotusuallypopulatedbynovelists.ButJosephFinderisjustsuchararity.Recent
ThecontroversialAnglo-Frenchsupersonictransportplane,theConcorde,hadattractedmuchattentionbecauseitisunusuallylo
ThecontroversialAnglo-Frenchsupersonictransportplane,theConcorde,hadattractedmuchattentionbecauseitisunusuallylo
Twofactorsweighheavilyagainsttheeffectivenessofscientificresearchinindustry.Oneisthegeneralatmosphereofsecrecy
随机试题
女性,25岁,停经2个月,不规则阴道出血15天,腹痛5天,妇科检查附件区可触及包块,超声检查见子宫增大程度与孕周不符合,官腔内见多个大小不等的无回声暗区,呈落雪样改变。该患者附件包块可能为
病例对照研究中,调查对象应当是
患者,男,30岁。黎明前泄泻,不思饮食,腹痛腰酸,肢冷乏力,舌淡苔薄白,脉沉迟无力。治疗应首选
法律作为一种行为规范,具有判断和衡量人们行为合法或不合法的作用。这是法律的()作用。(2011年单项选择第1题)
根据《建筑安装工程费用项目组成》的规定,规费包括()。
下列影响扣件式钢管脚手架的整体稳定性的因素中,属于主要影响因素的是()。
当材料、设备已用于或安装在永久工程之中时,材料、设备预付款应从进度付款证书中扣回,扣回期不超过()个月。
()是国民与行政人员之间联系的桥梁。
下列程序段()能够正确实现条件:如果X<Y则A=15,否则A=-15。
TherelationshipbetweentemperatureC,indegreesCelsius,andtemperatureF,indegreesFahrenheit,isgivenbytheformulaF
最新回复
(
0
)