Among the phrases you really, really do not want to hear from climate scientists are: "that really shocked us," "we had no idea

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问题     Among the phrases you really, really do not want to hear from climate scientists are: "that really shocked us," "we had no idea how bad it was," and "reality is well ahead of the climate models." Yet in speaking to researchers who focus on the Arctic, you hear comments like these so regularly they begin to sound like the thumping refrain from Jaws: annoying signs of something that you really, really wish would go away.
    Let me explain the phrases above. The "shock" came when the International Polar Year, a global organization studying the Arctic, froze a small vessel into the sea ice off eastern Siberia in September 2006. Norwegian explorer Fridtjof Nansen had done the same thing a century before, and his Fram, carried by the drifting ice, arrived eastern Greenland 34 months later. IPY scientists thought their Tara would take 24 to 36 months. But it reached Greenland in just 14 months, stark evidence that the sea ice found a more open, ice-free, and thus faster path westward thanks to Arctic melting.
    The loss of Arctic sea ice is well ahead of what the Intergovernmental Panel on Climate Change (IPCC) forecast, largely because emissions of carbon dioxide have topped what the panel—which foolishly expected nations to care enough about global warming to do something about it—predicted. "The models just aren’t keeping up with the reality of CO2 emissions", says the IPY’s David Carlson. Although policy-makers hoped climate models would prove to be alarmist, the opposite is true, particular in the Arctic.
    The IPCC may also have been too cautious on Greenland, assuming that the melting of its glaciers would contribute little to sea-level rise. Some studies found that Greenland’s glacial streams were surging and surface ice was changing into liquid lakes, but others made a strong case that those surges and melts were short-term aberrations, not long-term trends. It seemed to be stuck. More reliable data, however, such as satellite measurements of Greenland’s mass, show that it is losing about 52 cubic miles per year and that the melting is accelerating. So while the IPCC predicted that sea level would rise 16 inches this century, "now a more likely figure is one meter (39 inches) at the least," says Carlson. "Chest high instead of knee high." Hence the "no idea how bad it was."
    The frozen north had another surprise in store. Scientists have long known that permafrost, if it melted, would release carbon, aggravating global warming, which would melt more permafrost, which would add more to global warming, on and on in a feedback loop. But estimates of how much carbon is locked into Arctic permafrost were, it turns out, woefully off. It is about three times as much as was thought, about 1.6 trillion metric tons, which has surprised a lot of people," says Edward Schuur of the University of Florida. That 1.6 trillion tons is about twice the amount now in the atmosphere. And Schuur’s measurements of how quickly CO2 can come out of permafrost, reported in May, were also a surprise: 1 billion to 2 billion tons per year. Cars and light trucks in the US emit about 300 million tons per year.
    In an insightful observation in The Guardian this month, Jim Watson of the University of Sussex wrote that "a new kind of climate skeptic is becoming more common": someone who doubts not the science but the policy response. For instance, the G8, led by Europe, has vowed to take steps to keep global warming below 2 degrees Celsius by reducing CO2 emissions. We are now at 0.8 degree. But the amount of CO2 in the atmosphere is already enough to raise 2 degrees. The only reason it hasn’t is that the atmosphere is full
    of crap (dust and aerosols that contribute to asthma, emphysema, and other diseases) that acts as a global coolant. As that pollution is reduced for health reasons, we are going to blast right through 2 degrees, which is enough to aggravate droughts and storms, wreak havoc on agriculture, and produce a planet warmer than it’s been in millions of years. The 2 degree promise is an illusion.
What is the relationship between the melting of Arctic permafrost and global warming?

选项 A、The former is the effect of the latter.
B、The former is the cause of the latter.
C、The two interact as both cause and effect.
D、The two have little to do with each other.

答案C

解析 本题关键词是Arctic permafrost,问题是:北极永久冻土层融化和全球变暖之间的关系是怎样的?定位到第五段。根据第五段第二句,北极永久冻土层融化(the melting of Arctic permafrost)和全球变暖 (global warming)之间的关系是:永久冻土层融化会释放碳元素,加速全球变暖,这样一来会使更多永久冻土层融化,将进一步加剧全球变暖,长此以往,将会形成一个恶性循环。由此可见,二者互为因果关系(the two interact as both cause and effect),因此选项C属于全面概括,为正确答案。原文强调不只是一个简单的后者影响前者的关系,而是互相影响形成恶性循环,所以选项A、B、D均属于以偏概全。第五段:永久冻土层融化释放碳元素,加速全球变暖,形成恶性循环。
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