首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
The Greenhouse Effect Earth’s climate has been changing constantly over its 5-billion-year history. Sometimes, the clima
The Greenhouse Effect Earth’s climate has been changing constantly over its 5-billion-year history. Sometimes, the clima
admin
2010-09-10
37
问题
The Greenhouse Effect
Earth’s climate has been changing constantly over its 5-billion-year history.
Sometimes, the climate has warmed so that the oceans have risen and covered much of the Earth. Each of the changes may seem extreme, but they usually occurred slowly over many thousands of years.
Ancient Climate History
The first people arrived in America between 151 000 and 30, 000 years ago. During that time, much of North America was covered by great ice sheets. Some 14, 000 years ago, the last ice sheet began to melt very quickly. By 7, 000 years ago, the ice was gone.
This end to the ice ages caused big changes on the Earth. The changes caused many kinds of plants and animals to die. For example, mastodon-elephant-like animal-and other large mammals that preferred cold climates may not have been able to live in the warmer, drier conditions.
The Little Ice Age
Starting in the 14th century, Europeans lived through what is known as the "Little Ice Age." The Little Ice Age lasted for several hundred years. During the Little Ice Age, the advance of glaciers along with hard winters and famines caused some people to starve and others to leave their homes.
Recent Climate History
The Earth has warmed about 1°F in the last 100 years. And the four warmest years of the 20th century all happened in the 1990s. Periods of increased heat from the sun may have helped make the Earth warmer. But many of the world’s leading climatologists think that the greenhouse gases people produce are making the Earth warmer, too.
Scientists think the sea has risen partly because of melting glaciers and sea ice. When some glaciers melt, they release water into the sea and make it higher than it was before. Scientists also think that warmer temperatures in the sea make it rise even more. Heat makes water expand. When the ocean expands, it takes up more space.
What Might Happen?
Scientists are not fortune-tellers. They don’t know exactly what will happen in the future. But they can use special computer programs to find out how the climate may change in the years ahead. And the computer programs tell us that the Earth may continue to get warmer.
Together, the melting glaciers, rising seas, and computer models provide some good clues. They tell us that the Earth’s temperature will probably continue to rise as long as we continue increasing the amount of greenhouse gases in the atmosphere.
Scientists have to think like detectives. They look for clues to help them understand how the world works. Then they investigate the clues to find evidence -- real facts that can give them a better idea of what is going on. Here are some of the ways that scientists gather evidence about climate, both past and present:
Weather Stations
Weather stations help us find out the temperature on the surface of the Earth. Weather stations use special thermometers that tell us the temperature. They can be set up almost anywhere on land. Weather stations also can tell us how fast the wind is moving and how much rain falls on the ground during a storm.
Weather Balloons
Almost everyone likes balloons -- including scientists! Weather balloons are released to float high up into the atmosphere. They carry special instruments that send all kinds of information about the weather back to people on the ground.
Ocean Buoys
A buoy is an object that floats on water, and is often used to warn boats away from dangerous places in the ocean or on a river. But some buoys have special instruments on them. These buoys can tell us the temperature and other things about the conditions of the atmosphere.
Weather Satellites
Humans send satellites into space to travel around the Earth. The satellites send back information to scientists on the ground. Some of the information they give us is about the weather and the Earth’s temperature.
Ice Cores
Some scientists who want to find out more about climate study ice for clues. Not just any ice - they are studying the ice from glaciers that have been around for a very long time. They cut pieces of ice and look for air bubbles that were trapped in the ice hundreds or even thousands of years ago. The air bubbles help them discover what the climate used to be like on Earth. The evidence they uncover is creating a historical record of regional temperatures and greenhouse gas concentrations dating back 160, 000 years.
Sediment Analyses
Sediment is the earth and rock that has built up in layers over time. Scientists are learning a great deal about past climate from studying these layers. Sediment layering pro vides information about where glaciers have been in the past. Ocean sediments provide a map of how ocean currents have flowed in the past. And fossilized pollen found in sediment layers tells us about where different plants have grown in the past.
Tree Rings
You can tell how old a tree is by counting its rings because it grows a new ring every year. Tree rings also can tell us how much precipitation fell each year in the place where the tree lives.
What Does All of This Mean?
Weather stations, balloons, ocean buoys, and satellites tell us the Earth’s temperature today. Ice cores, sediment layers, and tree rings tell us about what the Earth’s climate has been like in the past. With this evidence, scientists are learning how climate changes over time.
What Are Scientists Still Unsure About?
How do clouds respond to changes in temperature and precipitation? How do oceans transport heat? How do climate and intense weather events like hurricanes affect each other? As scientists try to answer these and other questions, they will discover many more clues about how the Earth’s climate system works.
It may seem hard to believe that people can actually change the Earth’s climate. But scientists think that the things people do that send greenhouse gases into the air are making our planet warmer.
Once, all climate changes occurred naturally. However, during the Industrial Revolution, we began altering our climate and environment through agricultural and industrial practices. The Industrial Revolution was a time when people began using machines to make life easier. It started more than 200 years ago and changed the way humans live. Before the Industrial Revolution, human activity released very few gases into the atmosphere, but now through population growth, fossil fuel burning, and deforestation, we are affecting the mixture of gases in the atmosphere.
Since the Industrial Revolution, the need for energy to run machines has steadily in creased. Some energy, like the energy .you need to do your homework, comes from the food you eat. But other energy, like the energy that makes cars run and much of the energy used to light and heat our homes, comes from fuels like coal and oil-fossil fuels. Burning these fuels releases greenhouse gases.
Both weather balloons and ocean buoys can collect information about the temperature.
选项
A、Y
B、N
C、NG
答案
C
解析
Both weather balloons and ocean buoys can collect information about the temperature.词汇线索明显是weather balloons,ocean buoys,都是小标题内容,所以专门寻找这两个段落中是否出现 temperature的信息即可。观察后发现,前者的段落内没有这方面信息,所以正确答案NG。
转载请注明原文地址:https://kaotiyun.com/show/bU87777K
0
大学英语四级
相关试题推荐
Forthispart,youareallowed30minutestowriteacompositiononthetopicElectronicDictionariesAreNotGood.Youarerequ
Trytoseethingsfromtheotherperson’sperspective.Ifyouempathizewiththatperson,youmayrealizethatheorshewasact
Manyayoungpersonstellsmehewantstobeawriter.【M1】______Ialwaysencouragesuchpeople,butIalsoexpla
Manyayoungpersonstellsmehewantstobeawriter.【M1】______Ialwaysencouragesuchpeople,butIalsoexpla
Women’spositioninsocietyhasimprovedwhenthemiddleofthelast【M1】______century.Theynowenjoytherighttov
Women’spositioninsocietyhasimprovedwhenthemiddleofthelast【M1】______century.Theynowenjoytherighttov
Livinginasecondculturecanbelikeridingonarollercoaster.Sometimesforeignvisitorsareelated;sometimestheyaredep
Livinginasecondculturecanbelikeridingonarollercoaster.Sometimesforeignvisitorsareelated;sometimestheyaredep
GlobalWarmingandClimateChangeWhatAreGlobalWarmingandClimateChange?Globalwarmingandclimatechangereferto
随机试题
汉民族共同语的基础方言是()
“元曲四大家”指________、________、________、________。
某男孩,5岁,症见睡中遗尿,面色萎黄,纳差便溏,常自汗出。其病机为
下列哪些人员可以参加基本养老保险,由个人缴纳基本养老保险费?()
在累计投标询价报价阶段,询价对象管理的每个配售对象只能申报一次,一经申报不得撤销或者修改。()
甲公司销售A型号彩色电视机1000台,每俞不含增值税销售价格5000元,每台销售成本为4000元;同时回收100台A型号旧彩色电视机,每台回收价格为500元;款项均已收付。对于上述业务,下列会计处理正确的有()。
出租人既出租某项资产,又以该项资产为担保借入资金的租赁形式是()。
“揠苗助长”说明遵循()的重要性。
结合材料,回答问题:材料1中国革命和中国共产党的发展道路,是在这样同中国资产阶级的复杂关联中走过的……当我们党的政治路线是正确地处理同资产阶级建立统一战线或被迫着分裂统一战线的问题时,我们党的发展、巩固和布尔什维克化就前进一步;而如果是不正确地
Anexpertinanyfieldmaybedefinedasapersonwhopossessesspecializedskillsandiscapableofrenderingverycompetentser
最新回复
(
0
)