For more than a decade, scientists have been trying to determine whether climate change is linked to intense storms, such as 200

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问题     For more than a decade, scientists have been trying to determine whether climate change is linked to intense storms, such as 2005’s Hurricane Katrina. Meteorologist Michael Mann of Pennsylvania State University, and colleagues attacked the question by turning to the past. They looked through drill cores from coastal waters for signs that sediments had been disturbed by major storms. Eight sites along the U. S. East Coast and Puerto Rico provided a reliable record of the number of significant hurricanes going back about 1500 years. Other climate data and models added clues to water temperatures and hurricane intensity.
    As the researchers report tomorrow in Nature, they found strong evidence that Atlantic hurricane activity peaked about 1000 years ago, producing up to 15 hurricanes a year on average — a level matched in recent times only over the past decade and a half. At the time, according to estimates constructed from other geologic data, Atlantic water temperatures were relatively warm, "though not as warm as today," Mann says. And Pacific temperatures were relatively cool, thanks to La Nina events. Warmer Atlantic waters whip up more storms, but warmer Pacific temperatures tend to create stronger jet streams that break up those storms. So the twin conditions a millennium ago produced kind of a "Perfect Storm" for hurricanes, he explains.
    Of particular interest, the sediments reveal a close link between warmer water and the number of hurricanes during the past 150 years or so. Dropping temperatures produced seven or eight hurricanes a year, while a rising thermometer, such as in the earlier part of this decade, pushed the total to 15. "All other things being equal, " Mann says, "this suggests that we are indeed likely to see not only stronger hurricanes in the Atlantic but perhaps more of them" in the near future.
    Meteorologist James Eisner of Florida State University in Tallahassee agrees with the findings, but adds a caveat. The historical data do show that a link between warmer ocean temperatures and higher hurricane frequencies has existed for at least 1500 years, he says. However, there’s a high degree of uncertainty in the data. That and the fact that the physics explaining the link haven’t yet been established, Eisner explains, "indicate this is not the ’ smoking gun’ we’ve been looking for that would allow us to confidently project what will happen as the oceans continue to warm. "
Which of the following can’t be inferred from the findings of the researchers?

选项 A、Hurricane activity is indeed quite sensitive to climate.
B、La Nina events prevent more intense and frequent storms from happening.
C、Current climate conditions resemble those that led to peak Atlantic hurricane activity about 1000 years ago.
D、The increase in storm intensity and climate change are linked.

答案B

解析 推理判断题。通观全文。研究人员通过对过去1500年来飓风发生次数与海水温度关系的研究,发现飓风强度和发生次数与海水温度密切相关,据此推测,[A]与[D]说法正确。原文第二段第一句提到,1000年前平均每年发生飓风15次,后面补充说明了这和过去十五年中每年发生的飓风次数不相上下,再联系气候与飓风发生频率的关系推断[C]说法也正确。[B]是对第二段后半部分内容的曲解。实际上拉尼娜现象出现的那年也是大西洋飓风活动最频繁的一年。
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