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.
According to David Carlson, which one is true about the sea-level rise of Greenland?

选项 A、It would be 39 inches higher than the original seal-level.
B、It would be 16 inches higher than the original sea-level.
C、It is a short-term phenomenon rather than a long-term one.
D、It has little to do with the melting of the sea ice.

答案A

解析 本题关键词是David Carlson和sea—level rise of Greenland,问题是:根据戴维.卡尔森的观点,格陵兰岛海平面上升的情况如何?定位到第四段。根据第四段第五句,卡尔森认为格陵兰岛海平面(sea level)至少会上升1米(39英寸),is one meter (39 inches),水将会淹没到胸口而非仅仅是膝盖。因此选项A与原文一致,为正确答案。选项B属于张冠李戴,因为海平面将上升16英寸(16 inches)是IPCC的观点,而不是戴维.卡尔森的观点。根据第四段第一、二句,冰川融化对海平面上升造成的影响不大(contribute little to sea-level rise),以及海平面上升是暂时(short-term)的失常现象而非长久(long-term)趋势均为IPCC的观点。因此,选项C、D也属于张冠李戴。第四段:数据证明格陵兰岛冰川加速融化,海平面会上升,但后果尚不明确。
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