The mystery of the expansion of sea ice around Antarctica, at the same time as global warming is melting swaths of Arctic sea ice, has been solved using data from U.S. military satellites.
Two decades of measurements show that changing wind patterns around Antarctica have caused a small increase in sea ice, the result of cold winds off the continent blowing ice away from the coastline. “Until now these changes in ice drift were only speculated upon using computer models,” said Paul Holland at the British Antarctic Survey. “Our study of direct satellite observations shows the complexity of climate change.” The Arctic is losing sea ice five times faster than the Antarctic is gaining it, so on average, the Earth is losing sea ice very quickly. There is no inconsistency between our results and global warming.”
The extent of sea ice is of global importance because the bright ice reflects sunlight far more than the ocean, meaning temperature rises still further. This summer saw a record low in Arctic sea ice since satellite measurements began 30 years ago. Holland said the changing pattern of sea ice at both poles would also affect global ocean circulation, with unknown effects. He noted that while Antarctic sea ice was growing, the Antarctic ice cap—the glacier and snow pack on the continent was losing mass, with the fresh water flowing into the ocean.
The research on Antarctic sea ice, published in Nature Geoscience, revealed large regional variations. In places where warm winds blowing from the tropics towards Antarctica had become stronger, sea ice was being lost rapidly. “In some areas, such as the Bellingshausen Sea, the sea ice is being lost as fast as in the Arctic,” said Holland.
But in other areas, sea ice was being added as sea water left behind ice being blown away from the coast froze. The net effect is that there has been an extra 17,000 sq km of sea ice each year since 1978—about a tenth of a percent of the maximum sea ice cover.
Antarctica is a continent surrounded by an ocean, whereas the Arctic is an ocean surrounded by a continent. For that reason, said Holland, sea ice was not able to expand by the same mechanism in the Arctic as at the southern pole, because if winds pushed the ice away from the pole it quickly hit land.
Holland did the research with Ron Kwok at Nasa’s jet propulsion laboratory in California, where maps of sea ice movements were created from more than 5m individual daily measurements collected over 19 years. The maps showed, for the first time, the long-term changes in sea ice drift around Antarctica. Kwok said: “The Antarctic sea ice cover interacts with the global climate system very differently than that of the Arctic, and these results highlight the sensitivity of the Antarctic ice coverage to changes in the strength of the wind around the continent.”
1. The contradiction of changes in sea ice coverage at both poles has been made clear by______.
2. According to what Holland said, we can draw the conclusion that ______.
3. Which of the following statement is true according to the passage?
4. According to the passage, what is to be blamed for the melting sea ice?
5. Which of the following statement is NOT true?
问题1选项
A.data collected from satellites
B.twenty-year’s measurements
C.computer models
D.the British Antarctic Survey
问题2选项
A.we can rely on satellite to estimate changes in ice drift
B.his research results conflict with global warming
C.the location of Bellingshausen Sea is around the Antarctic
D.the Antarctic ice coverage is sensitive to changes in wind strength
问题3选项
A.The Arctic is losing sea ice as quickly as the Antarctic.
B.The Antarctic is losing sea ice much faster than the Arctic.
C.While some regions of the Antarctic are gaining sea ice, other regions of it are losing sea ice.
D.Sea ice is being lost in the Arctic, not the Antarctic.
问题4选项
A.The wind from the north.
B.The global warming.
C.Ecological unbalance.
D.Unknown factors.
问题5选项
A.Effective measures to curb global warming are not discussed in the passage.
B.The military satellites play a very important role in investigating the rise of sea level.
C.The Arctic sea level is at a record low.
D.The author finds a solution to the losing sea ice.
第1题:A
第2题:D
第3题:C
第4题:B
第5题:D
1.【试题答案】A
【试题解析】细节事实题。由题干可以定位到文中第一段第一句The mystery of the expansion of sea ice around Antarctica, at the same time as global warming is melting swaths of Arctic sea ice, has been solved using data from U.S. military satellites.（在全球变暖导致北极海冰融化的同时，南极洲周围海冰的扩张之谜已经通过美国军事卫星的数据得到了解决。）A选项“从卫星收集的数据”，文章第一段提到，南极洲周围海冰扩张，美国卫星的数据解决了这个问题，因此A选项正确。B选项“20年的测量”，文章所说，20年来的测量表明，南极洲周围不断变化的风模式导致了海冰的小幅增加，B选项可排除。C选项“计算机模型”，文章所说，冰川漂移的变化只是通过计算机模型推测出来的，而不是海冰覆盖范围，可排除C选项。D选项“英国南极考察队”，文章没有提到这个内容，可排除D选项。因此A选项正确。
2.【试题答案】D
【试题解析】推理判断题。D选项“南极冰的覆盖范围对风力强度的变化很敏感”，文章最后一段提到Antarctic ice coverage to changes in the strength of the wind around the continent.（这些结果突出了南极海冰覆盖对大陆周围风力强度变化的敏感性），D选项正确。选项A“我们可以依靠卫星来估计冰漂移的变化”，可以定位到文章第二段第二句Until now these changes in ice drift were only speculated upon using computer models.（到目前为止，这些冰川漂移的变化只是通过计算机模型推测出来的），这些冰川漂移的变化只是通过计算机模型推测出来的，没有提到卫星可以估计冰漂移情况，A选项可排除。选项B“他的研究结果与全球变暖相矛盾”，文章第二段最后一句There is no inconsistency between our results and global warming.（我们的研究结果与全球变暖并不矛盾），研究结果与全球变暖并不矛盾，可排除B选项。C选项“别林斯高森海位于南极附近”，文章并没有提到此内容，可排除。因此D选项正确。
3.【试题答案】C
【试题解析】推理判断题。C选项“南极一些地区的海冰正在增加，而另一些地区的海冰却在减少”，可以定位文章第二段第一句Two decades of measurements show that changing wind patterns around Antarctica have caused a small increase in sea ice.（20年来的测量表明，南极洲周围不断变化的风模式导致了海冰的小幅增加），可推测南极洲周围不断变化的风模式导致了海冰的小幅增加，以及文章第四段最后一句In some areas, such as the Bellingshausen Sea, the sea ice is being lost as fast as in the Arctic.（在一些地区，比如别林斯高森海，海冰的消失速度和北极一样快）。因此可知南极地区的海冰正在增加，其他地区的海冰正在减少，C选项正确。A选项“北极的海冰正在以和南极一样快的速度消失”，文章第二段倒数第二句The Arctic is losing sea ice five times faster than the Antarctic is gaining it, so on average, the Earth is losing sea ice very quickly.（北极海冰融化的速度是南极海冰融化速度的五倍，所以平均而言，地球海冰融化的速度非常快），A选项可排除。B选项“南极海冰的融化速度比北极快得多”，文章第二段倒数第二句The Arctic is losing sea ice five times faster than the Antarctic is gaining it, so on average, the Earth is losing sea ice very quickly.（北极海冰融化的速度是南极海冰融化速度的五倍，所以平均而言，地球海冰融化的速度非常快），B选项可排除。D选项“海冰正在消失的是北极，而不是南极”，可定位到文章倒数第四段第二句In places where warm winds blowing from the tropics towards Antarctica had become stronger, sea ice was being lost rapidly.（在从热带吹向南极洲的暖风变得更强的地方，海冰正在迅速消失），可排除D选项。因此C选项正确。
4.【试题答案】B
【试题解析】推理判断题。通读全文。B选项“全球变暖”，文章第二段最后一句There is no inconsistency between our results and global warming.（我们的研究结果与全球变暖并不矛盾），研究结果与全球变暖并不矛盾，可推测海冰的消失与全球变暖脱不开关系，B选项为正确答案。A选项“来自北方的风”，文章所说，风会造成海冰的减少，也会造成海冰的增加，A选项可排除。C选项“生态不平衡”，文章没有提到此内容，C选项可排除。D选项“未知因素”，文章已经有研究结果，不存在未知因素，D选项可排除。因此B选项正确。
5.【试题答案】D
【试题解析】推理判断题。D选项“作者找到了解决海冰融化的办法”，作者并没有找到解决海冰融化的办法，海冰的消失作用于环境变化，作者不可能找到办法，D选项正确。A选项“文章没有讨论遏制全球变暖的有效措施”，文章没有提到解决全球变暖的办法，可排除A选项。B选项“军事卫星在调查海平面上升方面起着非常重要的作用”，文章第一段最后一句has been solved using data from U.S. military satellites.（南极洲周围海冰的扩张之谜已经通过美国军事卫星的数据得到了解决），B选项正确，可排除。C选项“北极海平面处于历史最低水平”，文章第三段第二句This summer saw a record low in Arctic sea ice since satellite measurements began 30 years ago.（今年夏天，北极海冰数量创下了30年前卫星测量以来的新低），可排除。因此D选项正确。
