7.Masses of floating ice are so large that they dwarfs your ship,making you question whether your ship still can be spotted among such floating mountains.They are so improbable looking that you simply look in wonder.It seems that nothing that large could be natural-and then it strikes you that something so large could only be natural.
Now,people realize that as climate change is raising global temperatures,more icebergs are being born.Antarctica creates far more of them than Greenland,the source of bergs in Arctic waters.Antarctica's are also much larger,sometimes reaching the size of small countries.Recent data show the average atmospheric temperature has increased about 4.5°F in the western Antarctic Peninsula since the 1940s,making the region,among the fastest warming on earth.This jump has been shown in the recent breaking of major ice shelves along the Antarctic Peninsula.As a result,thousands of new icebergs have broken off,from ice shelves into the Southern Ocean at an accelerated rate.
Even as more icebergs are being created,scientists are learning that these beauties are far from inactive masses of ice.In fact,they strikingly alter their environments biologically,chemically,and physically,making them islands of life in the open sea.Observers at sea had long remarked that they attract seals,and seabirds,and divers had noticed that fish are more numerous near them than in the surrounding sea.Now scientists are learning just what the attraction is all about.
Depending on their size,location,and the season,icebergs can be nurturers or destroyers.During their existence-typically years from breaking off from an Antarctic or Greenlandic glacier to their gradual melting as they float into lower altitudes,they support animals on,around,even inside their splendid ice castle.They fertilize the ocean with nutrients,increasing sea creature production.Grounded bergs can shelter areas of the seafloor,protecting bottom-living creatures from free-floating icebergs.However,large bergs can also trap sea ice,preventing its annual breakup and thus stopping phytoplankton(浮游植物)from getting life-giving sunlight,breaking the food chain at its first link.…
Icebergs will continue to astonish and attract visitors to the polar regions with their size and extraordinary beauty.But now these frozen masses are taking on a new dimension of wonder as we uncover their vital role in the environment of polar seas.No longer can we look at icebergs as mere passive beauties.They are active agents of change,each one an icy oasis with a wake of life as it floats on its unstoppable oceanic journey to melting.
67.Why does the author mention "dwarfs your ship" in the first paragraph?D
A.To explain how natural icebergs are.
B.To show how powerful icebergs are.
C.To describe icebergs as floating ships.
D.To tell the unimaginable size of icebergs.
68.What can we learn from the passage?D
A.The temperature in Arctic is rising faster than that in Antarctica.
B.The ocean food chain breaks due to the melting of icebergs.
C.Floating icebergs help shelter bottom-living ocean creatures.
D.Global warming has kept bringing icebergs into being.
69.From the passage we can conclude that icebergs canA.
A.preserve ocean lifeB.carry ocean nutrients away
C.create a warm polar environmentD.keep sea animals away from polar seas
70.What is the author's attitude towards the icebergs?B
A.Cautious.B.Objective.C.Doubtful.D.Disapproving.
分析 本文属于说明文阅读,作者通过这篇文章主要向我们描述了目前全球变暖趋势明显,随着全球气温的不断上升,冰山数量不断增多.冰山是众多海洋生物赖以生存的,它的增多从生物、化学、物理等多个方面改变着环境,对海洋既有利也有弊.
解答 67.D 细节理解题.根据文章第一段Masses of floating ice are so large that they dwarfs your ship,making you question whether your ship still can be spotted among such floating mountains.大量浮冰是如此之大,他们让你的船如此矮小并质疑你的船能否在这些浮动的山之间被认出.可知文中提到的"使你的船变得矮小"的原因是为了说明这些浮冰不可想象的尺寸.故选D.
68.D 理解推断题.根据文章第二段…the average atmospheric temperature…among the fastest warming on earth.可知A项错误;根据第四段Grounded bergs can…from free floating icebergs可知C项错误;根据第四段However,large bergs…at its first link.可知B项不正确;根据文章第二段"Now,people realize that as climate change is raising global temperatures,more icebergs are being born"可知气候变化导致了全球气温上升,和更多冰川的诞生;故选D.
69.A.细节理解题.根据第四段"They fertilize the ocean with nutrients,increasing sea creature production."冰川给海洋施肥增加营养,能增加海洋生物生产;可知冰川可以庇护海洋生物;故选A.
70.B.推理判断题.通读全文,文章主要描述随着全球气温不断上升,冰山数量不断增多.冰山的增多从生物、化学、物理等多个方面改变着环境,对海洋既有利也有弊,可知作者只是在客观描述事实,并未表达任何个人观点,故选B.
点评 考察学生的细节理解和推理判断能力,做细节理解题时一定要找到文章中的原句,和题干进行比较,再做出正确的选择.在做推理判断题不要以个人的主观想象代替文章的事实,要根据文章事实进行合乎逻辑的推理判断.