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
The climate of earth has fluctuated quite a bit over the last 4.6 billion years of our planet’s history and it can be expected t
The climate of earth has fluctuated quite a bit over the last 4.6 billion years of our planet’s history and it can be expected t
admin
2013-06-02
52
问题
The climate of earth has fluctuated quite a bit over the last 4.6 billion years of our planet’s history and it can be expected that the climate will continue to change. One of the most intriguing questions in earth science is whether the periods of ice ages are over or arc we living in an "interglacial" period of time between ice ages?
The geologic time period we are now living in is known as the Holocene (全新世). This epoch began about 11,000 years ago which was the end of the last glacial period and the end of the Pleistocene (更新世) epoch. The Pleistocene was an epoch of cool glacial and warmer interglacial periods which began about 1.8 million years ago.
Since the glacial period known as the "Wisconsin" in North America and "Wrm’ in Europe when over 10 million square miles (about 27 million km2 ) of North America, Asia, and Europe were covered by ice, almost all of the ice sheets covering the land and glaciers in the mountains have retreated. Today, about ten percent of the earth’s surface is covered by ice; 96% of this ice is located in Antarctica and Greenland. Glacial ice is also present in such diverse places as Alaska, Canada, New Zealand, Asia, and California.
As only 11,000 years has passed since the last Ice Age, scientists can not be certain that we are indeed living in a post- glacial Holocene epoch instead of an interglacial period of the Pleistocene and thus due for another ice age in the geologic future. Some scientists believe that an increase in global temperature, as we are now experiencing, could be a sign of an impending ice age and could actually increase the amount of ice on the earth’s surface.
The cold, dry air above the Arctic and Antarctica carries little moisture and drops little snow on the regions. An increase in global temperature could increase the mount of moisture in the air and increase the amount of snowfall. After years of more snowfall than melting, the Polar Regions could accumulate more ice.
An accumulation of ice would lead to a lowering of the level of the oceans and there would be further, unanticipated changes in the global climate system as well. Our short history on earth and our shorter record of the climate keeps us from fully understanding the implications of global warming. Without a doubt, an increase in the earth’s temperature will have major consequences for all life on this planet.
Which of the following statements is TRUE according to the passage?
选项
A、96 percent of the earth’s surface is covered by ice.
B、Over 10 million square miles of the earth’s surface are covered by ice now.
C、Almost all of the ice sheets coveting the land and glaciers in the mountains have been hidden.
D、Most of the ice on the earth’s surface is located in Antarctic and Greenland for the time being.
答案
D
解析
细节题。文章第三段倒数第二句指出,如今地球表面的10%被冰覆盖,其中的96%分布在南极洲和格陵兰岛,所以D正确。
转载请注明原文地址:https://kaotiyun.com/show/l967777K
0
大学英语六级
相关试题推荐
A、Suggestatopicforaresearchpaper.B、Tellherwhattostudyforthehistorytest.C、Writeafavorableletterofrecommendat
IntheUnitedStates,itisrequiredthatallchildrenattendschool,publicorprivate,fortwelveyears.Thereare【B1】______t
IntheUnitedStates,itisrequiredthatallchildrenattendschool,publicorprivate,fortwelveyears.Thereare【B1】______t
______(这些水的痕迹使很多科学家相信)thattheremightbesomeformsoflifeonthatplanet.
A、Hehaslosthishistorybook.B、Hedoesn’tlikethehistorycourse.C、Hehastoreadalotofhistorybooks.D、Hefindshistor
"UnsolvedHistory"IfNASAengineersinventedatimemachinetomorrow,youcanbesurehistorianswouldbeshellingouttop
A、Itsscarceproteins.B、Itsterribletaste.C、Itsmanyvitamins.D、Thedifficultyoffindingit.BWhatisoneofthedrawbacks
A、OtherAmericanstates.B、Foreigncountries.C、Regionsoutsidethecitywherepeoplelive.D、Othercitiesinthestatewherepe
TelevisionhastransformedpoliticsintheUnitedStatesbychangingthewayinwhichinformationisdisseminated,byalteringp
ThehomeserviceindustryinBeijingisexpectedtobecomemoreattractivebothasajobandasanindustry.Sourcesatthe
随机试题
抽油机井分析包括哪些内容?
营养性缺铁性贫血的临床表现不包括
托儿所、幼儿园建筑护栏高度、栏杆间距、安装位置要求正确的是()。
下列合同不属于效力待定合同的类型的是( )。
根据《金融资产管理公司监管办法》,金融资产管理公司集团母公司资本充足率不得低于()。
某商贸企业,今年实现的产品销售收入1800万元,支付合理的工资薪金总额200万元(合残疾职工工资50万元),业务招待费80万元,职工福利费60万元,职工教育经费30万元,利润总额为200万元。另外,企业当年购置环境保护专用设备支出600万元,购置完毕即投入
简述高中美术课程“调节心理状态,促进身心健康”的表现。
三个工程队完成一项工程,每天两队工作、一队轮休,最后耗时13天整完成了这项工程。问如果不轮休,三个工程队一起工作,将在第几天内完成这项工程?
蓝鹰行动
下列叙述中正确的是
最新回复
(
0
)