首页
登录
职称英语
[img]2016m3x/ct_eyyjsbz2013j_eyyjsbreada_0100_20163[/img] Glaciers consist o
[img]2016m3x/ct_eyyjsbz2013j_eyyjsbreada_0100_20163[/img] Glaciers consist o
游客
2024-08-10
14
管理
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 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 world-wide 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 melt water from glaciers to their fields. Scientists and engineer shave worked together to tap into-glacial resources, using electricity that has been generated in part by damming glacial melt water. [br] Glacial melt water can be dammed to produce______.
选项
答案
electricity
解析
(文章最后一句话提到Scientists and engineers have worked together to tap into glacial re-sources,using electricity that has been generated in part by damming glacial melt water。)
转载请注明原文地址:https://tihaiku.com/zcyy/3713386.html
相关试题推荐
[img]2016m3x/ct_eyyjsbz2014j_eyyjsbreadd_0360_20163[/img]It’snoteasytou
[img]2016m3x/ct_eyyjsbz2014j_eyyjsbreadd_0360_20163[/img]It’snoteasytou
[img]2016m3x/ct_eyyjsbz2014c_eyyjsbreadd_0255_20163[/img]Oneofthegreats
[img]2016m3x/ct_eyyjsbz2014c_eyyjsbreadd_0255_20163[/img]Oneofthegreats
[img]2016m3x/ct_eyyjsbz2014c_eyyjsbreadd_0255_20163[/img]Oneofthegreats
[img]2016m3x/ct_eyyjsbz2014c_eyyjsbreadd_0255_20163[/img]Oneofthegreats
[img]2016m3x/ct_eyyjsbz2015c_eyyjsbreadc_0070_20163[/img]HowdidmodernWes
[img]2016m3x/ct_eyyjsbz2015c_eyyjsbreadc_0070_20163[/img]HowdidmodernWes
[img]2016m3x/ct_eyyjsbz2015c_eyyjsbreadc_0070_20163[/img]HowdidmodernWes
[img]2016m3x/ct_eyyjsbz2014j_eyyjsbreadc_0354_20163[/img]Guernicawasthel
随机试题
Ifsustainablecompetitiveadvantagedependsonwork-forceskills,American
[originaltext]W:ArtDepartment,thetreasurerBrownspeaking.M:Hello,Profes
Asthesayinggoeswell,"(practice)______makesperfect."practice这里用名词形式作主语。该句
24岁,GP,因患葡萄胎住院治疗40天,经清宫后行各项必要化验均在正常范围出院。
A.二尖瓣关闭不全 B.主动脉瓣关闭不全 C.纤维蛋白性心包炎 D.左侧胸
根据《建设工程工程量清单计价规范》,编制工程量清单的过程中,确定项目编码的紧后工
电气上聚集的触头元件是指属于同一控制开关的相邻触头元件,彼此间有足够的绝缘,能接
一房产公司投资3000万元购买了天津某高新技术开发区土地使用权150亩,经过半年
A.龙胆 B.坚龙胆 C.苏龙胆 D.苦龙胆 E.严龙胆根表皮膜质,木质
新生儿生理性体重下降发生在出生后A.第1周 B.第2周 C.第3周 D.第
最新回复
(
0
)