The argument that human-caused carbon emissions are merely a drop in the bucket compared to greenhouse gases generated by volcanoes has been making its way around the rumor mill for years.And while it seems to be reasonable，the science just doesn't back it up.
According to the US Geological Survey （USGS），the world's volcanoes，both on land and undersea，generate about 200 million tons of carbon dioxide annually，while our automotive and industrial activities cause some 24 billion tons of CO2 emissions every year worldwide.Despite the arguments to the contrary，the facts speak for themselves.Greenhouse gas emissions from volcanoes compose less than one percent of those generated by today's human activities.
Another indication that human emissions surpass those of volcanoes is the fact that atmosphere CO2 levels，as measured by sampling stations around the world，have gone up consistently year after year regardless of whether or not there have been major volcanic eruptions in specific years. "If it were true that individual volcanic eruptions dominated human emissions and were causing the rise in carbon dioxide concentrations，then these carbon dioxide records would be full of spikes-one for each eruption，" says Coby Beck，a journalist writing for online environmental news. "Instead，such records show a smooth and regular trend."
Furthermore，some scientists believe that volcanic eruptions，like that of Mt.St.Helens in 1980 and Mt.Pinatubo in 1991，actually lead to short-term global cooling，not warming，as sulfur dioxide （SO2），ash and other particles in the air and stratosphere reflect some solar energy instead of letting it into Earth's atmosphere.
Scientists tracking the effects of the major 1991 eruption of the Philippines' Mt.Pinatubo found that the overall effect of the blast was to cool the surface of the Earth globally by some 0.5 degrees Celsius a year later.
In an interesting twist on the issue，volcanic activity may be contributing to the melting of ice caps in Antarctica but not because of any emissions，natural or man-made.Instead，scientists Hugh Corr and David Vaughan of the British Antarctic Survey believe that volcanoes underneath Antarctica may be melting the continent's ice sheets from below，just as warming air temperatures from human-induced emissions erode them from above.
（1）According to Paragraph 1，some people argue that BB.
A．their opinion is supported by science
B．volcanoes generate most of the greenhouse gases
C．human activities are to blame for greenhouse gases
D．carbon emissions produced by volcanoes are increasing
（2）What does the underlined word "spikes" in Paragraph 3 probably mean？ AA
A．sudden increases.
B．smooth trends.
C．stable regularities.
D．sharp declines.
（3）According to this passage，what do the scientists believe about volcanic eruptions？ BB
A．They brought about global warming.
B．They actually partly cooled the surface of the Earth.
C．They melted the ice sheets in Antarctic from above.
D．They dominated human emissions in greenhouse effect.
（4）The purpose of the passage is to BB.
A．compare the results of the studies
B．contradict a view held by some people
C．present new findings for greenhouse phenomenon
D．report the effects of CO2 in greenhouse phenomenon
【考點(diǎn)】說明文．
【答案】B；A；B；B
【解答】
【點(diǎn)評(píng)】
聲明：本試題解析著作權(quán)屬菁優(yōu)網(wǎng)所有，未經(jīng)書面同意，不得復(fù)制發(fā)布。
發(fā)布：2024/4/20 14:35:0組卷：3引用：1難度：0.6
相似題
-
1．International students who stayed in the US as their classes moved online during the COVID may be forced to leave，following guidelines of the US Immigration and Customs Enforcement published due to the pandemic（流行?。?
"You know I don't want to put my family at risk，I don't want to put myself at risk to travel during a pandemic and go back to Pakistan，and even if I could delay the program for a year，it is not certain that I will get the visa again." said a Pakistani student.
Many students say they need to be in the US for more than attending cljye.ais.As a PhD student，the library is an extremely important resource for them，although it is because of COVED that those services have been closed，which means even this advantage is gone.
"You know more than 90% of the international students who were studying the US when COVID-19 hit and college campuses were closed have to remain in the US and this creates such trouble in their lives and such uncertainty that is unreasonable." said a lady from a university.
International students staving in the United States say the new ruling has disturbed their plans to return. "I know it is a fact that when it comes to rules，guidelines，laws and stuff like that，international students are sort of treated as low-level citizens.Even I can't even use the word "citizen" to begin with because that's what they make clear we are not."
The government said that the policy speaks for itself and that online coursework is not worth a visa.So far，not any sign of change has been within sight.As students are waiting for the policy to improve，their fall programming and their future remain in limbo.
（1）Why would international students prefer to stay in the US during the pandemic？
A．They couldn't delay the program for a year.
B．They can make full use of the library resource.
C．They wouldn't bring any potential danger to their family.
D．They can learn better with their classes moved online.
（2）What do international students staying in the United States think of the new rule？
A．The new rule treats them as American citizens.
B．The new rule shows great unreasonable opinion against them.
C．The new rule guides them to plan to return to the US.
D．The new rule treats them like low-level students in school.
（3）What is the government's attitude towards the new rule？
A．Favorable.
B．Neutral（中立）.
C．Unfavorable.
D．Unclear.
（4）What does the underlined phrase "in limbo" in the last paragraph mean？
A．Horrible.
B．Flexible.
C．Uncertain.
D．Unbelievable.發(fā)布：2025/1/6 15:30:8組卷：0引用：1難度：0.5 -
2．Most of us spend our lives seeking the natural world.We go fishing，sit in the garden，have a picnic，live in the suburbs or go to the seaside.The most popular leisure activity in Britain is going for a walk.When joggers jog，they don't run on the streets.Every one of them tends to go to the park or the river.
But despite this，our children are growing up naturedeprived（剝奪）.I spent my boyhood climbing trees.These days，children are robbed of the ancient freedom，due to problems like crime，traffic，the loss of the open space and strange new ideas about what is best for children，that is to say，things that can be bought，rather than things that can be found.
The truth is to be found elsewhere.A study in the US：families had moved to better housing and the children were assessed for ADHD—Attention Deficit Hyperactivity Disorder（注意力缺陷多動(dòng)癥）.Those whose accommodation had more natural views showed an improvement of 19%；those who had the same improvement in material surroundings but no nice view improved just 4%.
ADHD is one of the great problems of modern childhood.One study after another indicates that contact with nature gives huge benefits to ADHD children.However，we spend money on drugs rather than on green places.
The life of old people is measurably better when they have access to nature.The increasing concern for the growing population of old people is in quality rather than quantity of years.And study after study finds that a garden is the single most important thing in finding that quality.Even problems with crime and aggressive behaviour are reduced when there is contact with the natural world.
We need the wild world.It is essential to our wellbeing，our health and our happiness.
（1）According to the author，people enjoyto seek nature.
A．jogging on the street
B．running in the gym
C．shopping in the supermarket
D．sitting in the garden
（2）From the second paragraph，we can see that.
A．Children don't want to approach nature
B．children probably spend less time in nature nowadays
C．climbing trees will certainly do good to the children
D．children tend to be happier as a result of their material satisfaction
（3）In what way do people benefit from their contact with nature？
A．Children with ADHD can be cured.
B．Children's performance at school is greatly improved.
C．Problems with crime and violent behavior will easily be solved.
D．A garden nearby improves the quality of old people's life.
（4）what is the main idea of this passage？
A．Access to nature improves our life.
B．Nature treats children for ADHD.
C．Getting close to nature reduces crime.
D．Man can't live without natural areas.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
3．It is widely believed that biodiversity（生物多樣性）is promoted to save species.But in reality species exist only as part of ecosystems and cannot survive unless their ecosystems are protected along with as much as possible of the diversity they contain.
Protecting habitats（棲息地）is important for keeping biodiversity.In 2003，over 102，000 habitats covering nearly 19 million square kilometres，or 11.5% of the world's land surface，were under some form of protection.Though this is a great improvement since 1962，when just 1，000 protected habitats were listed，it is still not considered enough to stop the ecocide that is endangering the world's biodiversity.
For a number of environmentalist，protecting the world's 25 biodiversity hotspots（熱點(diǎn)地區(qū)）is critical to saving habitats and species.But many hotspots are endangered already，having lost up to three-quarters of their original plants.
The poor state of most biodiversity hotspots results directly from population growth and migration（遷移） into these areas.A study found that by the mid-1990s around 1.1 billion people lived in these hotspots.Moreover，the annual population growth rate in these areas was 1.8%，higher than the global average of 1.4%.The PAI report concluded that human-related environmental changes will continue to put pressure on hotspots.Therefore，keeping biodiversity requires paying close attention to population size.
Protecting hotspots is not simply a matter of putting up fences and employing guards.The best results are achieved when local people are educated about the value of wildlife，and actually gain a share of the benefits from eco-tourism.Only then do they have a chance to see the benefits of protecting hotpots.
（1）What can we infer from paragraph 1？
A．The loss of any species can affect humans.
B．Endangered species are paid more attention to by humans.
C．Species can still survive when their ecosystems are destroyed.
D．Ecosystem protection is as important as diversity protection.
（2）What does the underlined word "ecocide" in paragraph 2 mean？
A．Ecosystem protection.
B．Reduction of the number of species.
C．Serious damage to habitats.
D．Habitats protection.
（3）What's the direct cause of the terrible state of the hotspots？
A．Population growth in hotpots.
B．Migration out of these areas.
C．Global warming.
D．The global average population growth rate.
（4）What's the author's opinion on protecting the hotspots？
A．It's simple to carry out.
B．It leads to the increase of tourists.
C．It's closely connected with local people.
D．It suggests that the local people are well educated.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5
相關(guān)試卷