编辑点评: 研习GRE作文考试的优秀范文不仅可以学到有用的词汇和句子,更能从中学习逻辑的构建方式和作文框架的结构等内容,这里为大家提供GRE的范文,希望对同学们的备考有所帮助。
The concept of obtaining fresh water from icebergs that are towed to populated areas and arid 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 has 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 10000 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 desalinization, or removing salt from water.
下一篇: GRE写作范文——Bacteria
2017届高考英语一轮复习限时训练:7-4 Sharing(新人教版)
2017届高考英语一轮语法专题复习课件:7 非谓语动词(重大版)
2017届高考英语一轮语法专题复习课件:1 名词和冠词(重大版)
2017届高考英语一轮复习限时训练:7-2 Robots(新人教版)
2016年高考+联考模拟英语试题分项版解析:专题02 动词的时态和语态及情态动词(解析版)
近三年高考(2017-2016)英语试题分项版解析:专题24 图画式(原卷版)
2017届高考英语一轮复习限时训练:7-3 Under the sea(新人教版)
2017届高考英语一轮复习限时训练:4-3 A taste of English humour(新人教版)
近三年高考(2017-2016)英语试题分项版解析:专题07 非谓语动词(原卷版)
2017届高考英语一轮复习限时训练:3-4 Astronomy :the science of the stars(新人教版)
2016年高考+联考模拟英语试题分项版解析:专题01 词、短语辨析(名词、动词、形容词、副词、代词和介词)(原卷版)
2017届高考英语一轮复习限时训练:4-4 Body language(新人教版)
近三年高考(2017-2016)英语试题分项版解析:专题10 名词性从句(解析版)
2017届高考英语一轮复习限时训练:1-2 English around the world(新人教版)
2017届高考英语一轮复习限时训练:6-3 A healthy life(新人教版)
2017届高考英语一轮语法专题复习课件:3 介词和介词短语(重大版)
近三年高考(2017-2016)英语试题分项版解析:专题25 开放式(解析版)
2017届高考英语一轮复习限时训练:6-1 Art(新人教版)
2017届高考英语一轮复习限时训练:5-1 Great scientists(新人教版)
2016年高考+联考模拟英语试题分项版解析:专题02 动词的时态和语态及情态动词(原卷版)
2017届高考英语一轮复习限时训练:6-4 Global warming(新人教版)
2017届高考英语一轮复习限时训练:6-5 The power of nature(新人教版)
近三年高考(2017-2016)英语试题分项版解析:专题08 定语从句(原卷版)
2016年高考+联考模拟英语试题分项版解析:专题04 从句(原卷版)
2017届高考英语一轮复习限时训练:5-3 Life in the future(新人教版)
2016年高考+联考模拟英语试题分项版解析:专题04 从句(解析版)
2017届高考英语一轮复习限时训练:6-2 Poems(新人教版)
2017届高考英语一轮复习限时训练:4-2 Working the land(新人教版)
2017届高考英语一轮语法专题复习课件:10 定语从句(重大版)
近三年高考(2017-2016)英语试题分项版解析:专题10 名词性从句(原卷版)