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
Dr Corell heads a team of some 300 scientists who have spent the past four years investigating the matter in a process known as
Dr Corell heads a team of some 300 scientists who have spent the past four years investigating the matter in a process known as
admin
2013-06-12
21
问题
Dr Corell heads a team of some 300 scientists who have spent the past four years investigating the matter in a process known as the Arctic Climate Impact Assessment (ACIA). The group, drawn from the eight countries with territories inside the Arctic Circle, has just issued a report called "Impacts of a Warming Arctic", a lengthy summary of the principal scientific findings.
Scientists have long suspected that several factors lead to greater temperature swings at the poles than elsewhere on the planet. One is albedo (反照率)-the posh scientific name for how much sunlight is reflected by a planet’s surface, and how much is reflected. Most of the polar regions are covered in snow and ice, which are much more reflective than soil or ocean. If that snow melts, the exposure of dark earth (which absorbs heat) acts as a feedback loop that accelerates warming. A second factor that makes the poles special is that the atmosphere is thinner there than at the equator, and so less energy is required to warm it up. A third factor is that less solar energy is lost in evaporation at the frigid poles than in the steamy tropics.
Arctic warming may influence the global climate in several ways. One is that huge amounts of methane, a particularly potent greenhouse gas, are stored in the permafrost of the tundra. Although a thaw would allow forests to invade the tundra, which would tend to ameliorate any global warming that is going on (since trees capture carbon dioxide, the greenhouse gas most talked about in the context of climate change), a melting of the permafrost might also lead to a lot of trapped methane being released into the atmosphere, more than offsetting the cooling effects of the new forests.
Another worry is that Arctic warming will influence ocean circulation in ways that are not fully understood. One link in the chain is the salinity of sea water, which is decreasing in the north Atlantic thanks to an increase in glacial meltwaters. Because fresh water and salt water have different densities, this "freshening" of the ocean could change circulation patterns. The most celebrated risk is to the mid-Atlantic Conveyor Belt, a current which brings warm water from the tropics to north-western Europe, and which is responsible for that region’s unusually mild winters. Some of the ACIA’s experts are fretting over evidence of reduced density and salinity in waters near the Arctic that could adversely affect this current.
The biggest popular worry, though, is that melting Arctic ice could lead to a dramatic rise in sea level. Here, a few caveats are needed. For a start, much of the ice in the Arctic is floating in the sea already. Archimedes’s principle shows that the melting of this ice will make no immediate difference to the sea’s level, although it would change its albedo. Second, if land ice, such as that covering Greenland, does melt in large quantities, the process will take centuries. And third, although the experts are indeed worried that global warming might cause the oceans to rise, the main way they believe this will happen is by thermal expansion of the water itself.
Nevertheless, there is some cause for nervousness. As the ACIA researchers document, there are signs that the massive Greenland ice sheet might be melting more rapidly than was thought a few years ago. Cracks in the sheet appear to be allowing melt water to trickle to its base, explains Michael Oppenheimer, a climatologist at Princeton University who was not one of the report’s authors. That water may act as a lubricant, speeding up the sheet’s movement into the sea. If the entire sheet melted, the sea might rise by 6-7 metres. While acknowledging that disintegration this century is still an unlikely outcome, Dr Oppenheimer argues that the evidence of the past few years suggests it is more likely to happen over the next few centuries if the world does not reduce emissions of greenhouse gases. He worries that an accelerating Arctic warming trend may yet push the ice melt beyond an "irreversible on/off switch".
Not everybody wants to hear a story like that. But what people truly believe is happening can be seen in their actions better than in their words. One of the report’s most confident predictions is that the break-up of Arctic ice will open the region to long-distance shipping and, ironically, to drilling for oil and gas. It is surely no coincidence, then, that the Danish government, which controls Greenland, has just declared its intention to claim the mineral rights under the North Pole. It, at least, clearly believes that the Arctic ocean may soon be ice-free.
What does the author imply in the last paragraph by the sentence "But what people truly believe is happening can be seen in their actions better than in their words"?
选项
A、Not everybody wants to hear a story like that.
B、One of the report’s most confident predictions is that the break-up of Arctic ice will open the region to long-distance shipping and, ironically, to drilling for oil and gas.
C、The Danish government, which controls Greenland, has just declared its intention to claim the mineral rights under the North Pole.
D、None of the above.
答案
C
解析
作者在最后一段中说“我们更能从人们的行动而不是语言中看出什么才是他们正认为会发生的事情”,作者这样讲有何暗示?注意作者这句话中的讽刺语气。
转载请注明原文地址:https://kaotiyun.com/show/ow4O777K
0
专业英语八级
相关试题推荐
Manisoneofanumberofanimalsthatmakethings,butmanistheonlyonethatdependsforitsverysurvivalonthethingshe
Working-classfamiliesintheUnitedStatesareusuallynuclear,andmanystudiesindicatethatworking-classcouplesmarry
Bigcrimesdeservetoughresponses.Inanycountrythetheftandpublicationof250,000secretgovernmentdocumentswoulddeserv
WhichisthecorrectinformationabouttheBest361CollegessurveycarriedoutbythePrincetonReview?
Withtheconstructoroftherailwaysinthe19thcentury,anewsociologicalphenomenonwasborn:thetravelingcriminal.Until
Formostlearners,skilllearningbeginswiththecognitivestage.Duringthisstage,thelearnersareinstructedhowtodothe
StagesofSecondLanguageAcquisitionStageⅠ:【1】Period:1)inthisstage,moststudentsunderstand【2】thantheycanpro
HowmuchloanwillbeprovidedforthegovernmentofIreland?
A、theU.S.hasdetectedanIranianspyservicenetworkB、theU.S.hasbrokenthecodesusedinIranianspycommunicationsC、the
随机试题
改善过滤效果的关键是什么?
腹膜炎患者采用半卧位,其目的包括()。
一胎龄34周的新生儿,体温34℃,腋肛温差为正值,恢复正常体温的时间最好是( )。
城镇中发现甲类传染病和乙类传染病中的艾滋病、肺炭疽病的病人、病原携带者和疑似病人时,国家规定的报告时间是
患者,男,50岁。左下6缺失,设计双端固定桥时,对于固定连接体的要求正确的是
根据预算法律制度的规定,下列各项中,属于一般公共预算收入的有()。
英文字母A是中心对称图形.()
中国是一个农业社会,聚族而居、_______在农业大环境下,成了传统家庭的重心,由此而衍生出来的道德价值观,首先是儒家倡导的“亲亲”,形成长幼有序、孝悌仁爱的道德观念,并用家庭成员_______和继承下来的风俗习惯,有效地维护血缘秩序,履行个人在血缘等级关
①追求成熟,已经成为当今社会的一种_____________,尤其是涉世不深的年轻人,更想以老到、___________的面孔引起别人对自己的注意和重视。②事物的发展一旦停滞___________趋于保守,就将走向灭亡,___________为新生事物所取
Forsomeemployers,thepolicyoflifelongemploymentisparticularlyimportantbecauseitmeansthattheycanputmoremoneyand
最新回复
(
0
)