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题库解析   >   现象解释型题型   >   RC33-35篇
    本题由lindy提供
2967次学习
RC33-35篇

Since the 1850s researchers have tried to show that variations in seasonal weather are connected in some ways with sunspots

, the outward sign of an increase in the Sun's activity. However, sciences lacked evidence supporting such a link until the mid-1980s, when van Loon and Labitzke compiled statistical evidence suggesting that a link exists and that it involves winds in the upper atmosphere above the equator which reverse their direction from east to west or west to east, every twelve to fifteen months. This phenomenon is called the quasi-biennial oscillation (QBO), and although meteorologists have known about the QBO since the 1950s, until the 1980s no one recognized a subtle but statistically significant link between the QBO and certain pattern of weather. When the west to east direction of winds in the upper atmosphere coincides with periods of high solar activity that occur approximately every eleven years, winters in the eastern and central United States are very cold.

On this basis, some meteorologists predicted that the winter of 1988-1989 in the United States would be severe. However, the winter was a mild one overall, and the meteorologists' attempt to make the connection between the Sun and weather on the Earth appeared unsuccessful, until Barston and Liverzey proposed a hypothesis explaining why the prediction had failed. They argued that the prediction had not taken into account another important element in the climate: the more or less regular pattern of fluctuations in the temperature of the surface waters of the tropical Pacific Ocean.

Barston and Livezey noted that when the water temperature is abnormally high-the phenomenon called EL Nino—the changes of cold winter weather over North American increase. The opposite situation, when surface temperatures are well below normal—La Nina—is far less common. In fact, until late 1988 no one had seen the combination of La Nina, westerly winds in the upper atmosphere, and high solar activity.

Thus, according to Barston and Livezey, La Nina cancelled out the effect of the other two climatic factors and caused the mild winter of 1988-1989. Although this hypothesis is plausible, much research remains to be done before meteorologists can establish and explain the effects of increased solar activity on seasonal weather changes.

Which of the following most accurately describes the organization of

the passage?


    A. A hypothesis is presented, a theory is constructed on the basis of the hypothesis, and then further research to expand the scope of the theory is proposed.

    B.A hypothesis is presented, an example that contradicts it is described, and then a hypothesis accounting for the apparent contradiction is proposed.

    C. Two opposing hypotheses are stated, and evidence confirming one of the hypotheses is considered.

    D. A phenomenon is described, a prediction about that phenomenon is made, and evidence confirming the accuracy of the prediction is presented.

    E. A prediction about a phenomenon is detailed and evaluated, and evidence demonstrating the inaccuracy of the prediction is presented.


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答案:
B
首先提出了
猜想气候变化和太阳活动有关,sun activity和赤道上方的wind direction两种因素一起影响气候温度,根据这猜想预测了1988-1989年美国冬天将会非常严寒。预测失败之后,提出了新的猜想,temperature of the surface waters of the tropical Pacific Ocean.会影响气候。 就是先提出一个猜想,一个反例,然后提出另外一个猜想去解释这个反例,选B 选项A a theory is constructed on the basis of the hypothesis错误,并没有在这个猜想上面建立一个理论 选项C Two opposing hypotheses are stated错误,是一个是在之前一个的基础上提出 选项D evidence confirming the accuracy of the prediction is presented错误 选项E evidence s presented.错误,并没有列举出证据

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