首页
登录
职称英语
One day, drought may be a thing of the past, at least in any country not too
One day, drought may be a thing of the past, at least in any country not too
游客
2023-12-24
30
管理
问题
One day, drought may be a thing of the past, at least in any country not too far from the sea. Vast areas of desert throughout the world may for the first time come to life and provide millions of hectares of cultivated land where now nothing grows.
By the end of this century this may not be mere speculation. Scientists are already looking into the possibility of using some of the available ice in the Arctic and Antarctic. In these regions there are vast ice-caps formed by snow that has fallen over the past 50,000 years. Layer upon layer of deep snow means that, when melted, the snow water would be pure, not salty as sea-ice would be. There is so much potential pure water here that it would need only a fraction to turn much of the desert or poorly irrigated parts of the world into rich farmland. And what useful packages would come in! It should be possible to hack off a bit of ice and transport it! Alternatively perhaps a passing iceberg could be captured. They are always breaking away from the main caps and floating around, pushed by currents, until they eventually melt and are wasted.
Many icebergs are, of course, much too small to be towed any distance, and would melt before they reached a country that needed them anywhere. It would be necessary to harness one that was manageable and that was big enough to provide a good supply when it reached us. Engineers think that an iceberg up to 11 kilometres long and 2 kilometres wide could be transported if the tug pulling it was as big as a supertanker! Even then they would cover only 32 kilometres every day. However, once the iceberg was at its destination, say at one end of Hong Kong harbour, more than 7,000 million cubic metres of water could be taken from it! That would probably be more than enough for Hong Kong even in the hottest summer! But no doubt a use could be found for it.
Apparently, scientists say, there would not be too much wastage in such a journey. The larger the iceberg, the slower it melts, even if it is towed through the tropics. This is because when the sun has a bigger area to warm up, less heat actually gets into the iceberg. The vast frozen center would be unaffected.
Even with the giant tug that would have to be available to tow an iceberg seven miles long, the voyage would take many months from the Antarctic to Hong Kong, for example, but as stronger engines are built and more is known about sea currents, the journey could get shorter and shorter and thus the wastage less and less. Airline pilots have learnt to use jet streams ten miles above the earth to increase speed and save fuel so, surely, a boat towing an iceberg could make use of fast-flowing currents and avoid warmer water. [br] The difficulty of using ice to solve the drought problem lies in all of the following EXCEPT______.
选项
A、the proper equipment for transportation
B、the time taken on the journey
C、the storage of the fresh water
D、the proper size of icebergs
答案
C
解析
这是道细节题。这道细节题需要通读文中好几段才能找出。所以考生需要通读这几段。 “Engineers think that an iceberg up to 11 kilomctres long and 2 kilometres wide could be transported if the tug pulling it was as big as a supertanker!”(关键词11 kliometers,transport)“The larger the iceberg, the slower it melts, even if it is towed through the tropics.”“The vast frozen center would be unaffected. Even with the giant tug that would have to be available to tow an iceberg seven miles long, the voyage would take many months from the Antarctic to Hong Kong, for example.”(关键词:take many months)从三个句子可以看出,文中提到解决干旱碰到困难在于A:适当的运输设备,B:运送时间,D:适当的保留住冰块。唯独没有提及C。
转载请注明原文地址:http://tihaiku.com/zcyy/3300173.html
相关试题推荐
WhenIfirstcametothiscountry,IthoughtlittlethatIshouldstayheresol
Someobserverssaytherecentcoupofamilitarygovernmentinthatcountrywill
In1986thecountryinitiatedrestrictionsontheuseofpesticides.A、instituted
Heavyrainswerecausinginundationandmuchdamagethroughoutthecountry.A、muc
Itwastheir______decisiontoleavetheircountry,andasaresult,theylostth
Hewasonlya(n)________rulerofthecountry;therealonewashismother,who
Asthecrisisissweepingacrossthecountry,manyyoungpeople,especiallycoll
Thiscountry,withitsinstitutions,belongstothepeoplewhoinhabitit.Whene
Itisreportedthatalmost66%ofthelandinthewesternpartofthecountryar
Itwasherviewthatthecountry’sproblemshadbeenexacerbatedbyforeignaid,
随机试题
A—chefB—carpenterC—receptionistD—flig
个体在遇到新情境时,基本的适应方式包括()A.坚持自己的价值观 B.问题解决
课程实施计划的展开途径是()。A.组织教学活动 B.分析教学任务 C.安排课
Lb4A3133高频阻波器所起的作用是()。(A)限制短路电流;(B)补
下列关于地基处理及桩基的论述,何项是不正确的?( )[2014年真题]A.地基
Doyouknowwhere____now?A.helives B.d
(2018年真题)某企业于当年年初向商业银行A申请了一笔1000万元1年期专用机
(2017年真题)根据《证券公司为期货公司提供中间介绍业务试行办法》的规定,证券
水泥混凝土散水、明沟和台阶等与建筑物连接处应设缝处理。上述缝宽度为( ),缝内
预应力管桩下沉深度可超过( ),能经受较大振动荷载或施工振动,其管壁抗裂性较强
最新回复
(
0
)