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
考研
Glaciers consist of fallen snow that compresses over many years into large, thickened ice masses. Most of the world’s glacial ic
Glaciers consist of fallen snow that compresses over many years into large, thickened ice masses. Most of the world’s glacial ic
admin
2020-03-21
68
问题
Glaciers consist of fallen snow that compresses over many years into large, thickened ice masses. Most of the world’s glacial ice is found in Antarctica and Greenland, but glaciers are found on nearly every continent, even Africa. Presently, 10% of land area is covered with glaciers. Glacial ice often appears blue because ice absorbs all other colors but reflects blue. Almost 90% of an iceberg is below water; only about 10% shows above water. What makes glaciers unique is their ability to move. Due to sheer mass, glaciers flow like very slow rivers. Some glaciers are as small as football fields, whereas others grow to be over 100 kilometers long.
Within the past 750, 000 years, scientists know that there have been eight Ice Age cycles, separated by warmer periods called interglacial periods. Currently, the earth is nearing the end of an interglacial, meaning that another Ice Age is due in a few thousand years. This is part of the normal climate variation cycle. Greenhouse warming may delay the onset of another glacial era, but scientists still have many questions to answer about climate change. Although glaciers change very slowly over long periods, they may provide important global climate change signals.
The girth of the ice, combined with gravity’s influence, causes glaciers to flow very slowly. Once a mass of compressed ice reaches a critical thickness of about 18 meters thick, it becomes so heavy that it begins to deform and move. Ice may flow down mountains and valleys, fan across plains, or spread out to sea. Movement along the underside of a glacier is slower than movement at the top due to the friction created as it slides along the ground’s surface.
Most glaciers are found in remote mountainous areas. However, some found near cities or towns present a danger to the people living nearby. On land, lakes formed on top of a glacier during the melt season may cause floods. At the narrow part of a valley glacier, ice falling from the glacier presents a hazard to hikers below. When ice breaks off over the ocean, an iceberg is formed.
Glaciers are a natural resource and contain 75% of the world’s freshwater. People worldwide are trying to harness the power of these frozen streams. Some towns rely on glacial melting from a nearby ice cap to provide drinking water. Some farmers spread soil or ashes over snow to promote melting, hoping that the melting will provide water to irrigate crops in drought-stricken areas. Others have channeled meltwater from glaciers to their fields. Scientists and engineers have worked together to tap into glacial resources, using electricity that has been generated in part by damming glacial meltwater.
After reading the passage, what can one conclude about glaciers?
选项
A、There will not be another Ice Age coming.
B、Glaciers have both negative and positive effects on human life.
C、Scientists have difficulty studying glaciers.
D、Scientists have minimal data on the formation of glaciers.
答案
B
解析
推论题。本文通篇讲述了冰川的形成、变化以及给人类生活带来的各种影响。选项[A]文中未涉及;选项[B]符合全文信息总结后得出的结论;选项[C]虽有涉及(第二段后半部分提到,温室效应可能会推迟另一个冰河时代的到来,但气候变化方面的诸多问题仍然有待科学家们回答。)但并非可以通过全文得出的结论;选项[D]文中未涉及。因此,正确答案为[B]。
转载请注明原文地址:https://kaotiyun.com/show/96Y4777K
0
考研英语二
相关试题推荐
ThemajordifferencebetweennarrativesalesandsuggestivesalesisthatWhichofthefollowingisthebesttitleforthepass
To______theworldpeacehasbeenoneofthemostcrucialfunctionsoftheUnitedNationssinceitwasfoundedin1945.
WhichofthefollowingbestdescribestheAmerica’seconomicsituation?Howdoesmonetarypolicyofferhelpforweakeconomica
1.Whenpeopleindevelopingcountriesworryaboutmigration,theyareusuallyconcernedattheprospectoftheirbestandbright
MillionsofAmericansandforeignersseeG.I.Joeasamindlesswartoy,thesymbolofAmericanmilitaryadventurism,butthat’
MillionsofAmericansandforeignersseeG.I.Joeasamindlesswartoy,thesymbolofAmericanmilitaryadventurism,butthat’
Priortothe20thcentury,manylanguageswithsmallnumbersofspeakerssurvivedforcenturies.Theincreasinglyinterconnected
Thereweresomeconsistentpatternsamongtheheavierreaders:Fortheyoungerchildren—ages6to11—beingreadaloudtoregula
Runningmaybethesinglemosteffectiveexercisetoincreaselifeexpectancy,accordingtoanewreviewandanalysisofpastre
Runningmaybethesinglemosteffectiveexercisetoincreaselifeexpectancy,accordingtoanewreviewandanalysisofpastre
随机试题
不属于ACEI类药物禁忌证的是
Theyalwaysgivetheirvacantseatsto______comesfirst.
减小几何模糊,正确的措施是
患者妊娠36周,突然发生剧烈腹痛,面色苍白,血压降至80/60mmHg,脉弱,腹部检查子宫硬如板状,有压痛,胎位触不清,胎心听不清,宫口开大1cm。本病症最恰当的处理是
监理工程师对承包商( )的工程量,不予计量。
进口国要求提供海关发票主要是作为其海关减免关税的依据。
一般来说,居民委员会需要下设哪些委员会()。
(2012年真题)民事权利的私力救济方式包括
Forthispart,youareallowed30minutestowriteashortessayentitledCareerorMarriage?.Youshouldwriteatleast150wor
聘金(endowment)是中国传统习俗的一部分。通常,新郎(bridegroom)需要给新娘家一笔钱作为聘礼来定下婚礼。但是近几年来其标准不断上升,致使大多数家庭都很难达到。快速上涨的生活成本是聘金增加的主要原因。对于大多数年轻人来说,结婚意味着独立组建
最新回复
(
0
)