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 concept of obtaining fresh water from icebergs that are towed to populated regions of the world was once treated as a joke m
The concept of obtaining fresh water from icebergs that are towed to populated regions of the world was once treated as a joke m
admin
2014-09-28
74
问题
The concept of obtaining fresh water from icebergs that are towed to populated regions of the world was once treated as a joke more appropriate to cartoons than real life. But now it is being considered quite seriously by many nations, especially since scientists have warned that the human race will outgrow its fresh water supply faster than it runs out of food.
Glaciers are a possible source of fresh water that have been overlooked until recently. Three quarters of the Earth’s fresh water supply is still tied up in glacial ice, a reservoir of untapped fresh water so immense that it could sustain all the rivers of the world for 1, 000 years. Floating on the oceans every year are 7, 659 trillion metric tons of ice encased in 10, 000 icebergs that break away from the polar ice caps, more than ninety percent of them from Antarctica.
Huge glaciers that stretch over the shallow continental shelf give birth to icebergs throughout the year. Icebergs are not like sea ice, which is formed when the sea itself freezes; rather, they are formed entirely on land, breaking off when glaciers spread over the sea. As they drift away from the polar region, icebergs sometimes move mysteriously in a direction opposite to the wind, pulled by subsurface currents. Because they melt more slowly than smaller pieces of ice, icebergs have been known to drift as far north as 35 degrees south of the equator in the Atlantic ocean. To corral them and steer them to parts of the world where they are needed would not be too difficult.
The difficulty arises in other technical matters, such as the prevention of rapid melting in warmer climates and the funneling of fresh water to shore in great volume. But even if the icebergs lost half of their volume in towing, the water they could provide would be far cheaper than that produced by desalination, or removing salt from water.
The main idea of the passage is about______.
选项
A、the movement of glaciers
B、icebergs as a source of fresh water
C、future water shortages
D、the future of the world’s rivers
答案
B
解析
转载请注明原文地址:https://kaotiyun.com/show/pvXd777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
Thereisadifferencebetweenscienceandtechnology.Scienceisamethodofansweringtheoretical(31);technologyisamethod
Thereisadifferencebetweenscienceandtechnology.Scienceisamethodofansweringtheoretical(31);technologyisamethod
Thereisadifferencebetweenscienceandtechnology.Scienceisamethodofansweringtheoretical(31);technologyisamethod
Thereisadifferencebetweenscienceandtechnology.Scienceisamethodofansweringtheoretical(31);technologyisamethod
Fromhervantagepointshewatchedthemaindoomswingopenandthefirstarrivalspourin.Thosewhohadbeenattheheadofth
Whereispopulationgrowthhappening?
StrongYuanPreventsAsia-wideCollapseCHINAwillcontinuetokeeptheyuanstablethisyear,saidanarticleintheFinanc
PersonnelchangesattheInternationalMonetaryFundandproposalsforchangingthefundhavebeenreportedlately.Afteraleng
inGermany
随机试题
肾交感神经节后纤维释放的去甲肾上腺素可调节
代谢性碱中毒的代偿中,哪项是恰当的
腺体鳞状上皮化生后发生恶性变,所形成的恶性瘤称为
最适于地面消毒皮肤
上市公司及其控股股东或实际控制人最近36个月内存在未履行向投资者作出的公开承诺的行为,不得公开发行证券。()
定势是一种消极的心理活动准备状态。()
外交家考虑问题显然不如法学家那么___________,也不如经济学家那样“___________”,能否就某一议题达成共识完全取决于国内政治力量的妥协和谈判桌上的临场发挥。至于最后谈判文本对本国福利的影响以及如何从法律上得以保证文本的执行,外交家们保留了
简述新闻本源和来源的区别。(中南财经政法大学,2008年)
Ibecameinterestedinwritingatanearlyage.Sowhenmyfourth-gradeteachertoldmeabouta【C1】________writer’sconference
Jason:Hi,Jane.Doyouhaveanychange?Ihavetomakeacallonthepayphone.Jane:______
最新回复
(
0
)