第六篇 Arctic Melt (C级)
Earth’s North and South Poles are famous for being cold and icy. Last year, however, the amount of ice in the Arctic Ocean fell to a record low.
Normally, ice builds in Arctic waters around the North Pole each winter and shrinks during the summer. But for many years, the amount of ice left by the end of summer has been declining.
Since 1979, each decade has seen an 11.4 percent drop in end-of-summer ice cover. Between 1981 and 2000, ice in the Arctic lost 22 percent of its thickness -becoming 1.13 meters thinner.
Last summer, Arctic sea ice reached its skimpiest levels yet. By the end of summer 2007, the ice had shrunk to cover just 4.2 million square kilometers. That’s 38 percent less area than the aver-age cover at that time of year. And it’s a very large 23 percent below the previous record low, which was set just 2 years ago. This continuing trend has scientists concerned.
There may be several reasons for the ice melt, says Jinlun Zhang, an oceanographer at the University of Washington in Seattle. Unusually strong winds blew through the Arctic last summer. The winds pushed much of the ice out of the central Arctic, leaving a large area of thin ice and open water.
Scientists also suspect that fewer clouds cover the Arctic now than in the past. Clearer skies allow more sunlight to reach the ocean. The extra heat warms both the water and the atmosphere. In parts of the Arctic Ocean last year, surface temperatures were 3.5°Celsius warmer than average and 1.5°C warmer than the previous record high.
With both air and water getting warmer, the ice is melting from both above and below. In some parts of the Beaufort Sea, north of Alaska and western Canada, ice that measured 3.3 m thick at the beginning of the summer measured just 50 centimeters by season’s end.
The new measurements suggest that melting is far more severe than scientists have seen by just looking at ice cover from above, says Donald K. Perovich, a geophysicist at the U. S. Army Cold Regions Research and Engineering Laboratory in Hanover, N.H.
Some scientists fear that the Arctic is stuck in a warming trend from which it may never recover.
练习：
1. Which of the following is closest in meaning to the word “build” in the first sentence of the second paragraph?
A) Construct.
B) Extend.
C) Create.
D) Expand.
2. What is the ice cover in the Arctic by the end of 2007 summer?
A) 4.2 million square kilometers.
B) 11.4 million square kilometers.
C) 1.13 million square kilometers.
D) 38 million square kilometers.
3. What are the reasons for the ice melt according to the scientists?
A) Strong winds and clear skies.
B) Long summer and short winter.
C) Open water and thin ice.
D) Light clouds and light winds.
4. Why is the ice melting from both above and below?
A) Because extra heat warms the air.
B) Because extra heat warms the water.
C) Because the temperature above the water is higher.
D) Both A and B.
5. What can be a possible title for the passage?
A) What are scientists looking for in the Arctic Ocean?
B) What are scientists doing in the Arctic Ocean?
C) Why are scientists worrying about the Arctic Ocean?
D) Why are scientists interested in the Arctic Ocean?
2010职称英语理工阅读新增文章-第6篇参考答案
D A A D C
2010职称英语理工阅读新增文章-第6篇参考译文
第六篇 北极冰山融化
地球的北极和南极都以冰冷闻名。但是，去年北冰洋上的冰含量跌到了历史最低点。
正常情况下，每年冬天在北极附近的北冰洋开始结冰，并在夏天缩减。但是多年以来，在夏天结束时冰的含量在下降。
自从1979年以来，每10年在夏季末的冰覆盖量都下降11．4％。在1981到2000年之间，北极冰的厚度下降了22％——变成了1．13米这么薄。
去年，北极的冰雪覆盖达到了最薄的程度。在2007年夏天快结束的时候，冰层已经缩减到只覆盖四百二十万平方公里。这比那年的平均覆盖面积少38％，比两年前最低记录少23％。这个持续的趋势令科学家们万分担忧。
冰雪融化有许多原因，西雅图华盛顿大学的海洋学家张金伦说，有许多原因导致了冰层融化。极不寻常的强风去年刮过大西洋，风把大西洋中部的冰散去，留下大面积的薄冰和没有冰覆盖的海面。
科学家们还怀疑在大西洋上空有比过去越来越少的云层。晴朗的天空使更多的阳光照射大西洋。升高的温度使水和空气都变温暖。在去年大西洋的部分海域，表面温度比平均温度高3．5摄氏度，比历史最高点还高1．5摄氏度。
由于空气和水都变暖，冰从上面和下面都开始融化。在波弗特海的部分海域，阿拉斯加的北部和加拿大的西部，夏天开始时冰的厚度为3．3米，但到了季末仅仅为50厘米。
新的测量表明，情况远远比科学家们仅仅从表面上看到的要严重得多，新罕布什尔州汉诺威市的地球物理学家Donald K．Perovich说。
一些科学家担心北极已经深陷变热的趋势不能恢复。
2010年职称英语考试教材现货已到，先到先得，欲购从速！
