Question

    Air travel is growing around the globe, and so is its contribution to climate change. The climate cost of flying has drawn more public attention in recent years, even leading to“ flight shame” in some places, especially for local or avoidable flights.

And while a decline in air travel would help with climate change，flight shame can also be added by other ways that make air travel more environmentally friendly. That includes switching to cleaner，renewable fuel , but as a new study indicates , there's also another, less obvious option: flying at lower altitudes.

In a new study, researchers used computers to predict how adjusting aircraft altitudes might reduce the number of contrails(尾迹)，which we see as white lines across the sky containing black carbon particles (颗粒)，thus reducing their warming effect. The study found that aircraft would only need to adjust their altitudes by about 2 ,000 feet, and since some flights have a larger climate effect than others , only a small part of flights would need to make any adjustments.

Of course flying at a lower altitude might increase flying time and it also means burning significantly more fuel, and thus giving off more C02, but the benefits of controlling contrails are worth it.

In addition to changing altitudes，better engine technology could also help control contrails, the researchers add, since black carbon particles are produced by incomplete fuel combustion ( 燃烧). With more efficient engines, aircraft could reportedly reduce their contrail by as much as 70%。Combined with slight altitude adjustment for a small part of flights, this could help reduce overall contrail problems by 90%，the study suggests.

This is promising, but more research i still needed, and it may be a while before improvements like these take effect at a significant scale. So, while it's good to know air travel can have a smaller effect on the climate, for now the best way to achieve that is often by simply staying on the ground whenever possible.

1.What might be the effect of“flight shame" ?

A.People will avoid traveling by plane.

B.Airline companies will limit service targets.

C.The cost of air travelling will become higher.

D.People will feel shamed if they haven't taken a plane.

2.Why did the researchers suggest flying at lower altitudes?

A.Planes can travel faster. B.Planes can save more fuel.

C.Planes may give off less C02. D.Planes may have less warming effect.

3.What is mainly talked about in paragraph 5?

A.A way to change altitudes. B.The future of engine technology.

C.An approach to reducing contrails. D.The concept of incomplete combustion.

4.In which section of a website might this text appear?

A.Energy. B.Climate.

C.Finance. D.Safety. .

Answer

1.A

2.D

3.C

4.B

【解析】

本文是一篇说明文。作者介绍了一项新的研究发现，如果飞机在较低的海拔飞行，则能减少飞机对大气的不良影响，从而能够降低温室效应。

1.

推理判断题。根据第一、二段内容可知，飞行耻辱会让人们感觉自己坐飞机是在增加碳排放，造成更多的温室气体，对气候的恶化起到了推波助澜的作用，因此人们会减少乘坐飞机旅行。故选A。

2.

细节理解题。根据第三段第一句In a new study, researchers used computers to predict how adjusting aircraft altitudes might reduce the number of contrails(尾迹). which we see as white lines across the sky containing black carbon particles (颗粒)，thus.reducing their warming effect 可知，在一项新的研究中，研究人员使用计算机来预测如何调整飞机高度来减少飞机尾迹的数量，我们看到的天空中含有黑碳颗粒的白线，从而减少了它们的变暖效应。可以判断出研究人员建议低海拔飞行是因为飞机会减少增温影响。故选D。

3.

主旨大意题。根据本段首句In addition to changing altitudes，better engine technology could also help control contrails, the researchers add（除了改变高度，更好的引擎技术也可以帮助控制尾迹，研究人员补充说，因为黑碳颗粒是由不完全的燃料燃烧产生的）,结合本段内容可知，本段主要介绍的是减少飞机尾迹的另一种办法。故选C。

4.

推理判断题。文章主要讲了研究人员发现，如果飞机在较低的海拔飞行，则能够减少飞机对大气的不良影响，从而能够降低温室效应。由此推断，这篇文章应该出现在气候版面。故选B。