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  3. Planes may account for only 2 per cent of the world’s carbon emissions, but it is a figure destined to rise. The aviation indust

Planes may account for only 2 per cent of the world’s carbon emissions, but it is a figure destined to rise. The aviation indust

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问题     Planes may account for only 2 per cent of the world’s carbon emissions, but it is a figure destined to rise. The aviation industry is expanding at a dramatic rate, around 5% a year. Twice as many passengers are likely to be passing through British airports in 2020 compared with today, and three times by 2030.
    As the developed world acknowledges climate change warnings, the carbon emissions from other industries will fall. The aviation industry’s output will therefore account for an even larger percentage of emissions. One calculation, by the Climate Change Research(CCR), suggests the U. K. aviation industry could end up accounting for every gram of our carbon quota by 2040. Such calculations suppose aircraft designers cannot clean up their act, a suggestion firmly rejected by experts who point to a massive research program aimed at cutting fuel use by planes by around 50% by 2020, a move that would also halve their carbon emissions.
    To reach that aim, a key factor will be lightweight composites, materials made of several components, including carbon fibers. These are as strong and flexible as metal but as light as plastic. Planes such as the Airbus A340 are already made of material that is 10 per cent carbon composite. This cuts weight, decreases fuel use and reduces carbon emissions. The next generation of aircrafts, will make even more use of composites: a tremendous saving in weight, fuel and carbon.
    Then there is the simple matter of air traffic control. At present, individual countries have their own routes for aircraft crossing their airspaces. "Essentially aircraft travel on doglegs across Europe, and that is very inefficient in terms of fuel use," said Dr. John Green, of the Royal Aeronautical Society. "We need to rationalize air traffic control so that planes fly in straight, energy-efficient lines, an idea that is now being discussed in the EU. "
    Finally, there is aviation fuel. Making it ecologically friendly poses the greatest challenges of all. Biofuels can be used as petrol and diesel substitutes for cars and lorries, but not in planes. "Biofuel is essentially alcohol, and that burns at the wrong temperature for aircraft engines," says Green. "We can use coal to make kerosene, which we could burn in aircraft engines, but that does not help the issue of global warming, of course. " But this does not stop scientists from dreaming. One idea, put forward by the U. S. geneticist Craig Venter last week, would be to create micro-organisms, fitted with artificial chromosomes, which could convert sunlight into fuels that could be burnt in aircraft. These would not involve burning fossil carbon and would be the perfect green fuel. It is still a far-off prospect but realistic, say biologists.
The fact that passengers passing British airports will double or even triple indicates that
选项 A、the British aviation industry is growing very rapidly.
B、more and more British people tend to choose flying when traveling.
C、the aviation industry develops much faster than other industries in developed countries.
D、the aviation industry will cause more pollutants when compared with other industries.
答案D
解析 途经英国的机场的乘客人数将翻番，甚至翻两倍，这一事实表明[A]英国航空业发展迅速。[B]越来越多的英国人出行选择搭乘飞机。[C]在发达国家，航空业的发展比其他行业快得多。[D]和其他行业相比，航空业将产生更多的污染物。题干所提到的数据实例，表面上是描述乘客数量增加，英国航空业会迅速发展，但是根据本文的主题，开篇就提到了carbon emissions的问题。再根据第二段前两句可以判断，实际上是在说明航空业的快速发展会导致更多的碳排放量，其排放量所占比重和其他行业相比也会随之增长。因此选[D]。[A]、[B]、[C]三项只是涉及表面现象，没有揭示背后的实质含义。
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