托福模拟试题 -TPO20-讲座2- 题目详解以及译文

时间 : 2013-06-11 18:21来源 : VOA官网 收听下载次数 :

1 答案:B

解析:Professor: ... however , for the latest interglacial period, the one we are in now, this pattern did not hold, that is, the concentration of carbon dioxide and methane dipped a little bit after, uh, uh, after peaking at the beginning, near the beginning of the interglacial period, but then it began to rise again. Um ... What was different about this interglacial period than the other ones? ... Now, scientists have tended to regard ... the ... uh ... agricultural revolution as a beneficiary of the ... uh ... fortuitous shift in climate. 通过以上设问及全文来看,教授的主题是提出了个理论,由于人类的活动使得 climate cycle 发生变化。

2 答案:AD

解析:Professor: ...It’s kind of ironic to think that absent that effect, it maybe that we would be heading into an Ice Age again. In fact, back in the 1970s, a lot of theorists were predicting that, you know, the climate would start to cool and we’d slowly enter into the new Ice Age. And then they were puzzled as to why it didn’t seem to be happening.

3 答案:D

解析:Professor: ... When you grow crops and uh, pasture your animals, one of the things you do is you cut down the forests. If you cut down the forests, when you burn the trees for fuel and don’t replace them with other trees, or when you just leave them to rot and don’t allow other trees to grow, you end up with a lot more carbon in the form of carbon dioxide getting into the atmosphere. Um ... another gas associated with the spread of agriculture is methane. Methane forms in large concentration above wetlands, and as it turns out, the cultivation of certain grains creates vast areas of artificial wetlands, and probably drastically increases the amount of methane getting into the atmosphere, over and above what would be there. 根据上述讲解可知,原因是some certain gases 在大气中的quantities 增加。

4 答案:AD

解析:Professor: ... When you grow crops and uh, pasture your animals, one of the things you do is you cut down the forests. If you cut down the forests, when you burn the trees for fuel and don’t replace them with other trees, or when you just leave them to rot and don’t allow other trees to grow, you end up with a lot more carbon in the form of carbon dioxide getting into the atmosphere. Um ... another gas associated with the spread of agriculture is methane. Methane forms in large concentration above wetlands, and as it turns out, the cultivation of certain grains creates vast areas of artificial wetlands, and probably drastically increases the amount of methane getting into the atmosphere, over and above what would be there. 根据教授的解释,predicted ice age 的延迟到来是由于carbon dioxide 和methane 等气体在大气中的含量增加,而增加的原因从上文看是因为the clearing of trees 和the cultivation of certain grains.

5 答案:D

解析:Professor: ... Um... so we are entering into uncharted territory now, in terms of the amount of carbon dioxide, the concentrations of carbon dioxide that are now being put into the atmosphere as a result of industrialization and the use of fossil fuels 从上述内容可知,教授对于工业化的结果对气候的影响是进入了一个 uncharted territory,即未知的内容。
 

教授:我希望能和同学们一起回顾一万一千年前的气候问题,当时,地球进入了最近的一次间冰期。所谓间冰期,指的是两次冰河世纪的相间的时间段。当气候暖和了之后一段时间,冰原就会消退,直到气候重新变冷,另一次冰河世纪开始,而在此之间就是所谓的间冰期。在过去的几百万年里,地球的主要气候特征实际上是冰河纪,但实际上它也有规律地解冻,而上一次解冻,就发生在一万一千年前。我们之前学习过的间冰期的几种气候模式,其中一种是大气中二氧化碳和甲烷含量达到峰值,即在间冰期的开端,大气中的温室气体(二氧化碳和甲烷)含量是最多的。之后,因为一些现在还不是特别明确的原因,温室气体的聚集逐渐下降。那么,为什么气候还一直变得更加暖和呢?是因为,气候的变化相对于温室气体含量的变化存在一定的延迟。但是,嗯,随着温室气体的含量降到一定水平,地球的温度又重新开始下降,最终回到冰冻状态。嗯,但是,在最后一次间冰期之后,即我们现在所处的时代里,这种模式就不适应了。虽然在进入间冰期之后,甲烷和二氧化碳的含量自达到峰值以后有所下降,但之后它又开始上升了。嗯,这一次间冰期和之前的间冰期,有什么不同呢?这次间冰期和之前的相比,最重要的不同,在于人类的活动。

人类种植庄稼,圈养牲畜来获取食物,而不是猎取它们。这是农业的重大革命。而且,这项革命发生在一万一千年前的早期。现在,科学家们都倾向于认为农业革命是,嗯,受益于偶然性的气候变化的。但是,一些新的气候理论学家提出了许多新的气候学理论,提出,自从此次间冰期的开始后的农业革命开始,人类的活动一直都在影响自然气候。当我们种植农作物,喂养牲口时要做的第一件事情就是砍伐森林。当森林被伐之后,人类就把木头作为燃料,并且没有换植其他的植株;或者我们把砍得的木头烂在地里让别的植物没法生长,这样?慕峁牵芏嗵荚鼗嵋远?化碳的形式存在,并进入大气层。另一种随着农业扩张而过量产生的其他是甲烷。甲烷在沼泽上大批形成,而且,随着谷物种植面积的扩大,一大批人造湿地被制造出来,大量增加了进入大气层的甲烷含量,超过了以往的应有的水平。总之,嗯,农业的扩张,我们这里谈论的是成千上万年的农业扩展史,而且这段时间内的农业扩张对地球大气层的成分有着分厂深远的影响。有的科学家忽略了这种影响的存在,认为我们将再次缓慢进入冰河世纪。实际上,回溯到 1970 年代,许多环境理论专家就预测过气候的再次变冷,世界再次重新进入冰河世纪的发生。之后,他们被事实弄得很困惑:为什么地球还没有变冷?嗯,现在,气候变化对我们的未来意味着什么呢?嗯,这其实非常的微妙。我的意思是,人们既可以认为,这个间冰期的人类活动,农业革命是有益的;我们可以认为,这种温室气体的增加,是一种好的现象,因为它推迟了进入冰河世纪的时间。但是,其后的工业革命,大大增加了人类向空气中注入二氧化碳的总量;化石燃料的消耗往大气中灌注了海量的二氧化碳,总之,工业革命的到来使得化石燃料大量消耗,大气层的二氧化碳含量高度聚集。