Scientists say human activity contributes to ...

Scientists say human activity contributes to climate change, but they do not agree on the rate_______ climate change may be developing.

A. with which    B. with that       C. at which      D. at that

高三英语单项填空中等难度题查看答案及解析

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. .

高三英语阅读理解中等难度题查看答案及解析

Scientists studying the impact of climate change on the Arctic need to consider ways to reduce their own carbon footprints(碳排放量), says Ryan Brook, a researcher who regularly flies north to study the health of caribous(驯鹿).He calls on scientists to show leadership by examining and sharing ways to reduce the impact of working in polar regions.

“The importance of the research is not at question here. It is important to our understanding of and adapting to climate change. But we need to think about better approaches,” says Brook.

“This is an issue for all scientists, though polar researchers often travel particularly long distances using commercial air travel. We also rely extensively on small aircraft, icebreakers, and snowmobiles, all of which produce large amounts of carbon.”

Brook studies the health of caribou herds in Nunavut and Northwest Territories. He works with northern wildlife managers. This work typically takes him north five or six times per year and when he calculated his own carbon footprint, he was not happy with the result.

“My research footprints are about the same as the annual footprints of an average Toronto resident. Basically, I have two footprints — my own personal life, which is moderate, and my research footprint.”

Climate scientists can rightly argue that Arctic research is a specialized field and the community of scientists who travel north is relatively small. Even if all scientists working in the north reduced their carbon emissions, it would not make a big impact on the global scale. For Brook, it’s the option that matters.

There are ways researchers can reduce the amount of carbon they use. Some helicopters use less fuel than others. Solar and wind power are alternatives to gas-fired generators. And while carbon offsets(抵消) don’t reduce the amount of carbon emitted, they are an easy first step.

“There aren’t necessarily any easy answers, but we need to start talking about it,” says Brook. “This is particularly important for the next generation of scientists being trained and I hope to see them become leaders in this issue.”

1.What did Brook find when he calculated his own carbon footprints?

2. Brook’s opinion is challenged by the statement that ________.

3.We can infer from the last paragraph that ________.

4.What’s the main idea of the text?

高三英语阅读理解中等难度题查看答案及解析

Plants are flowering faster than scientists predict in reaction to climate change, which could have long damaging effects on food chains and ecosystems.

“Global warming is having a great effect on hundreds of plant and animal species around the world, changing some living patterns.” scientists say.

Increased carbon dioxide (CO2) in the air from burning coal and oil can have an effect on how plants produce oxygen, while higher temperatures and changeable rainfall patterns can change their patterns of growth.

“Predicting species’ reaction to climate change is a major challenge in ecology,” said the researchers of several U.S. Universities. They said plants had been the key object of study because their reaction to climate change could have an effect on food chains and ecosystem services.

The study, published on the Nature website, uses the findings from plant life cycle studies and experiments across four continents and 1,634 species. It found that some experiments had underestimated the speed of flowering by 8.5 times and leafing by 4 times.

“Across all species, the experiments underestimated the speed of the advance—for both leafing and flowering—that results from temperature increases,” the study said.

“The design of future experiments may need to be improved to better predict how plants will react to climate change,” it said.

Plants are necessary for life on the Earth. They are the base of the food chain, using photosynthesis (光合作用) to produce sugar from carbon dioxide and water. They let out oxygen which is needed by nearly every organism on the planet.

Scientists believe the world’s average temperature has risen by about 0.8 ℃ since 1900, and nearly 0.2 ℃ every ten years since 1979.

So far, efforts to cut emissions of planet-warming greenhouse gases are not seen as enough to prevent the Earth heating up beyond 2 ℃ this century—a point scientists say will bring the danger of a changeable climate in which weather extremes are common, leading to drought, floods, crop failures and rising sea levels.

1.What is the key information the author wants to give in Paragraph 1?

A. The increasing speed of flowering is beyond scientists’ expectation.

B. Climate change leads to the change of food production patterns.

C. Plants’ reaction to weather could have damaging effects on ecosystem.

D. Food chains have been seriously damaged because of weather.

2.We can learn from the study published on the Nature website that _____.

A. scientists should improve the design of the experiments

B. plants’ flowering is 8.5 times faster than leafing

C. there are 1,634 plant species on the four continents

D. the experiments failed to predict how plants react to climate change

3.Scientists pay special attention to the study of plants because _____.

A. they can prove the climate change clearly

B. they are very important in the food chains

C. they play a leading role in reducing global warming

D. they are growing and flowering much faster than before

4.What can be inferred from the last two paragraphs about the world’s temperature?

A. It has risen nearly 0.2 ℃ since 1979.

B. It is 0.8 ℃ higher in 1979 than that of 1990.

C. It needs to be controlled within 2 ℃ in this century.

D. Its change will lead to weather extremes.

高三英语阅读理解中等难度题查看答案及解析

Climate change will bring and has already brought a wide variety of threatening destruction to human existence. Some of these are well-known and already operative, like the wildfires racing along California’s freeways or the permanent droughts that have been upsetting Mediterranean farmers. But are these all terrible disasters we can come up with that are brought about by climate change?

Absolutely not. None of the challenges posed by our warming climate has appeared larger in the popular imagination than sea-level rise, as global populations and wealth are heavily concentrated in low-lying coastal cities. The best available models suggest that 37 million people currently live in places that will be below high tide by 2050-in an optimistic low-carbon-emissions scenario (设想).

Or rather, that’s what such models suggested before this week. On Tuesday, a new study revealed that those alarming statistics were wildly inaccurate. The actual impacts of sea-level rise are going to be much, much worse.

Previous estimates of the impact that rising tides would have on coastal cities relied on essentially a three-dimensional map of Earth obtained from satellite readings. But those readings were fundamentally unreliable because they often measured the planet’s upper surfaces — such as treetops and tall buildings — rather than its ground level. These mistakes led scientists to overestimate the elevation (海拔) of many regions of Earth.

In a new study published by the journal Nature Communications, scientists from Princeton, University detail this methodological problem, then use artificial intelligence to determine the previous literature’s error rate. Their research yields some amazing updates to our conventional understanding of what the next century has in store for our coastlines.

In its optimistic scenario, the Princeton study projects that lands currently occupied by 150 million people will lie below high tide in 2050. But as warming destroys many of the world’s agricultural regions, climate change could accelerate migration from rural areas to coastal cities.

The new study does include one piece of slightly encouraging news. While previous models suggested that 28 million humans currently live in places that already lie below high tide, the actual number is closer to 110 million — which means seawalls and other barriers have proven sufficient to keep many cities dry even as sea levels have risen around them. Still, the scale of barrier construction necessary to save low-lying cities from collapse is now, apparently, far greater than previously understood when the task already looked terribly expensive, particularly for developing countries.

If the Princeton researchers’ projections are correct, avoiding mass death and suffering in the coming decades will require not only rapidly reducing carbon emissions and strengthening construction of seawalls but also furthering mass migrations away from low-lying cities and islands and toward higher ground.

1.The first paragraph is mainly intended to 　　　　 .

A.introduce the topic of this passage

B.show various disasters caused by climate change

C.call on people to fix attention on climate change

D.lay emphasis on the seriousness of climate change

2.All the following statements are true EXCEPT　　　　 .

A.the Princeton study reveals an optimistic picture of sea rising. . .

B.the three-dimensional map produced by satellite is not accurate

C.some measures are mentioned by the writer to deal with sea rising

D.more people are likely to live in coastal cities in the coming years

3.We can see something encouraging from the Princeton study that 　　　　 .

A.it’s cheap to construct seawalls as well as other barriers

B.the scale of barrier construction is much greater than before

C.developed countries have less trouble in dealing with rising sea levels

D.seawalls do have the function to prevent coastal cities being drowned

4.What can be a suitable title for the passage?

A.How to protect cities from rising seas.

B.Rising seas are going to drown more cities.

C.Climate change is endangering human existence.

D.Less emission of carbon, fewer fires and droughts.

高三英语阅读理解简单题查看答案及解析

Now _____ understanding of climate change is no longer limited to ____ small group of scientists or environmentalists.

A. / ; a            B. an ; a              C. the ; the            D. a ; /

高三英语单项填空中等难度题查看答案及解析

Scientists say it may be five years ______ it is possible to test this medicine on human patients．

A. since                B. until                C. before           D. when

高三英语单项填空中等难度题查看答案及解析

Scientists say it may be five or six years _____ it is possible to test this medicine on human patients.

A. since                   B. after                   C. before     D. when

高三英语单项填空中等难度题查看答案及解析

Scientists say it may be five or six years _____ it is possible to test this medicine on human patients.

A. since　　　　　　　　 B. after　　　　　　 C. before　　　　　　 D. When

高三英语单项填空中等难度题查看答案及解析

Scientists say it may be one year or so ________ it is possible to test the new medicine on human patients.

A. when              B. after                C. before          D. since

高三英语单项填空中等难度题查看答案及解析