球变暖带来最主要的威胁是极地冰盖的融化，并给出了相应的事实和数据加以证明。接着更多例子表明南极洲的冰盖在过去的130万年间至少坍塌过一次。相关高等学府的学者和科学家也相继用实验证明南极洲西部曾是一片汪洋。最后引用Herman Engleheart的话，再次提醒我们，西南极洲大冰原很可能再次融化消失。

其实按常理来说，如果听力文章比较有难度的话，题目的难度相对应会降低。所以大家在遇到此类题型时不必惊慌。提取关键信息、边听边记笔记，运用好背景知识等就能把题目做出来。平时也要注意扩大阅读范围，增长见识。关于环境保护和全球变暖之类的文章屡见不鲜，要求考生在这方面要引起足够的重视。

难点词汇：

West Antarctic ice sheet西南极洲大冰原 ice shelf 冰架 anchored 固定的

fossil 化石 microscopic marine plants 海洋微生物 geological 地质的

答案及解析：

26. What is one of the most frightening threats of global warming according to the passage?

【解析】C) Many coastal cities will be covered with water.

细节题。本题不难，从听力开头即可听到“raising sea level so much that coastal cities from New York to Los Angles to Shanghai will be flooded”所以选C选项。

27. What do scientists disagree on?

【解析】B) How unstable the West Antarctic ice sheet is.

细节题。本题不难。注意关键句“but Antarctic experts disagree strongly on just how unstable it is”即可得出答案。

28. What is the latest information revealed about the West Antarctic ice sheet?

【解析】A）It collapsed at least once during the past 1.3 million years.

细节题。注意提取关键信息“new evidence reveals that all or most of the Antarctic ice sheet collapsed at least once during the past 1.3 million years”所以选A选项。

29. What the scientists’ latest findings suggest?

【解析】A) The West Antarctic region was once a open ocean.

细节题。听力最后的例子说明了这一点“which suggest that the region was once open ocean