在备考过程中，深入分析托福综合写作真题及听力原文是把握出题思路的关键。下面，我们就来看一篇具体的听力材料，它针对同一话题的阅读文章提出了不同的科学见解。
First, about the Gulf Stream.
Scientists now know that disrupting the Gulf Stream would cause cooling only in Europe and North America,
but the Little Ice Age also affected the Southern hemisphere, in places like New Zealand and Southern Africa for example.
Since the disruption of the Gulf Stream cannot explain why these southern areas became colder, it cannot explain the Little Ice Age.
Second. the volcanoes theory.
1t's true that if volcanic eruptions put enough dust into the atmosphere, the result can be a cooler climate.
But large amounts of volcanic dust in the atmosphere would have also produced striking visual effect that people would have noticed at the time.
For example. Dramatically colorful Sunsets or snow being grey or brown instead of white.
But there are almost no reports of anything like that routinely happening during the Little Ice Age.
So it seems that the volcanic eruptions during that period were simply not strong enough to release the large amounts of dust needed to lower global temperatures.
Third, about forests on farmland stopping the warming greenhouse effect by removing carbon dioxide.
There just was not enough time for this effect to work.
The human population grew back to previous levels fairly quickly,
which meant that forests were soon being cut down again to clear fields for the crops needed to feed the growing population.
As a result, we know that the forests mentioned in the reading passage were not there long enough to cause the long—term global cooling of the climate.
通过对这篇听力材料的梳理，我们可以清晰地看到其如何逐一反驳阅读观点。这种针对性的反驳逻辑，正是我们研究托福综合写作真题及听力原文时需要重点学习和模仿的核心技巧。
