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Global Warming论文

Global Warming

Abstract：

Global warming is an increase in the earth's temperature due to fuels, industry, and agricultural processes caused by human, natural, and other gas emissions. This results in an increased emission of greenhouse gases. Short-wave solar radiation sinks into the Earth's atmosphere and warms its surface; while long wave infrared radiation emitted by earth's surface is absorbed, and then

re-emitted by trace gases.Climate changes occur in our earth's atmosphere due to a buildup of greenhouse gases. Greenhouse gases can occur naturally as well as a result of human activities. Problems can occur when higher concentrations of greenhouse gases are present in our atmosphere because they have enhanced our earth's heat trapping capability.

Key words:Global warming Greenhouse gas

Introduction：

1.What is the climate problem-Global warming?

Global warming and climate change are terms for the observed century-scale rise in the average temperature of the Earth's climate system and its related effects.

Global warming happens when the earth heats up, this is obviously due to the rise in temperature. There are many skeptics that say otherwise. The earth is heating up, the temperature of the atmosphere and the temperature of the oceans are rising.Global warming is happening because of several key factors, the first one is greenhouse gases like carbon dioxide,water vapor,and methane. These greenhouse gases trap heat and industry is one of the leading causes of carbon dioxide becoming trapped in our atmosphere.

There are many misconceptions about global warming. Some believe that pollution causes global warming, but the fact is global warming is the result of burning fossil fuels, coal, and oil that release carbon dioxide. Another misconception is nuclear power causes climate change. Nuclear power actually reduces emissions of carbon dioxide when used in place of coal. Some believe that global warming means that it will become warmer all over. The name is misleading because in some places, it will actually become colder. The majority of scientists believe global warming is a process underway and that it is human-induced.

2.The effect of Global warming .

Global warming, what effect does it have on the environment? Well global warming can have many effects, and the effects are definitely not good! Global warming can cause many things like mess with the sea level, affect the weather and so on. Global warming effects the environment in

bad ways, and if it is not at least attempted to be stopped, it is only going to get worse. One effect global warming has on the environment is it affects sea level. Global warming raises the overall temperature and cause glaciers and ice caps to melt, which makes the water expand. When this happens, sea levels tend to rise more rapidly than normal. According to the Third Assessment Report by the Intergovernmental Panel on Climate Change, the sea level is expected to rise as much as 88 centimeters in the next century.Ocean acidification is also affected by global warming. Carbon dioxide is one of the greenhouse gases that cause global warming. So due to the rise in sea levels and precipitation, the carbon dioxide is mixed more with sea water. According to a report in the ―Open Democracy‖, this is a major concern for ocean life, especially coral. Most importantly, global warming effects weather. Global warming can affected the weather by making the climate hot or cold, or making it switch back and forth. Global warming is also believe to be the reason for so many bad hurricanes and earthquakes. [1]Although global warming is bad, there are ways to try and prevent it. Just by driving less and taking a bike or walking can help prevent global warming. Cutting down on your garbage can also help, just by buying fewer packaged materials can help prevent global warming. Most importantly, recycling can help. Buying recycled paper products and recycling as much as possible, is a great way to prevent global warming.So many things can be effected just by global warming, but it can also be prevented. Global warming is considered to be the main problem with our environment. So whether global warming is real or not, lets try to prevent it, because the environment is important!

3.Greenhouse gases.

As we all know, greenhouse effect is the absorption and emission of infrared radiation by gases in the atmosphere of a planet warm the lower atmosphere and surface. Source of curbing the greenhouse effect, and that is to reduce the production of greenhouse gases Among the main gas causing the greenhouse effect are: CO2,N2O,CH4etc.[2]

CO2: is raw material for synthesis of carbohydrates of plant photosynthesis. It can be increased to increase light and products, good for agricultural production. However, excessive CO2 emissions, but is also the main culprit of global warming. Rapid increase in CO2 has two causes: 1, since the industrial revolution, the excessive use of fossil energy, emit large amounts of CO2. 2, forest trees, deforestation, reduces the absorption of CO2 by photosynthesis.

CH4: in a environment by methane produced by bacteria or biological corruption. According to statistics the annual methane levels in the atmosphere will be a net increase of 350tg, while it is in the atmosphere, there is an average life expectancy of about 8 years, and extremely difficult to consume through chemical reaction.

N2O: there is life in the atmosphere is about 150 years, despite being chemically inert, solar radiation can also be used to break 90%, the rest of the 10% reaction and active oxygen atom consumed. But even so the atmosphere of N2O in 3TG annual net increase rate.

4.The way to solve this problem in our daily life.

So I think everyone under obligation to keep a balance between the CO2 emission and the uptake of CO2. About this condition, The department for environment, food and rural affairs designed a special calculator, which was called carbon footprint calculator. So, what’s the carbon footprint calculator? This is a software you can use it to complete the amount of carbon dioxide you produced. And you also can use it to figure up how many trees can absorb these carbon dioxide in the same time. And the carbon footprint calculation formula is:

E=Q*C[3]

Nowadays, our country also have this kind calculator software. We can find it in the web extremely. You can use it to count how much carbon dioxide about everything you did in the daily life. Under this condition, you will find what you should do to reduce the carbon dioxide emission is the most effect. And the following is some Suggestions to reduce carbon emissions in our daily life.

Stop driving cars to reduce seventy-six percent of the Thirty-four percent in the transportation sector which also reduce the Twenty-eight percent petroleum refining of the Twenty-eight percent Industrial sector.Reduce the heating level temperatures this winter by two degrees or more.Work four days a week at the office or work from home to reduce the lighting and heating loads on large buildings plus keep the car in the garage.[4]

Conclusions：

Fortunately, we can take actions to slow down global warming. Global warming results primarily f rom human activities that release heat-trapping gases and particles into the air. The most important causes include the burning of fossil fuels such as coal, gas, and oil, and deforestation. To reduce t he emission of heat-trapping gases like carbon dioxide, methane, and nitrous oxides, we can curb our consumption of fossil fuels, use technologies that reduce the amount of emissions wherever po ssible, and protect the forests in the world. We can also do things to mitigate the impacts of global warming and adapt to those most likely to occur,e.g., through careful planning and other strategies that reduce our vulnerability to global warming. But we can’t stop there. We are also advocating p olicies that will combat global warming over the long term, things like clean cars that run on altern ative fuels, environmentally responsible renewable energy technologies, and stopping the clear-cut ting of valuable forests. Clearly, global warming is a huge problem. It will take everyone — gover nments, industry, communities and individuals working together to make a real difference. Fortuna tely you can be part of them.

References:

[1]Changnon, Stanley A.; Bell, Gerald D. (2000). El Ni?o, 1997–1998: The Climate Event of the Century. London: Oxford University Press.

[2]Ramanathan, V.; Carmichael, G. (2008). "Global and regional climate changes due to black carbon". Nature Geoscience1 (4): 221–227

[3]WikipeEngland, Matthew (February 2014). "Recent intensification of wind-driven circulation in the Pacific and the ongoing warming hiatus".

[4]dia(Alexander) , L.A, (2015) Global

warming(title) ,//https://www.wendangku.net/doc/b39339060.html,/wiki/Global_warming(source),p（63-166）

unit4globalwarming单词和句型重点总结

Unit 4 Global warming全球变暖一、词汇 about发生；造成注意：（1）come about是不及物动词短语，不能用于被动语态，常指情况不受人控制的突然发生。有时用it作形式主语，that从句作真正主语。（2）表示“发生”的词或短语有：happen,occur,take place,break ① Many a quarrel comes about through a misunderstanding. ② The moon came out from behind the clouds. ③ I’ll let you know if anything comes up. ④ I’ll come over and see how you are coming along. ⑤ I came across an old friend yesterday. ⑥ When she came to, she couldn’t recognize the surroundings. ① I subscribe to your suggestion. ② Which magazine do you subscribe to? ③ He subscribed his name to the paper（文件）. ④ He subscribed a large sum to the poor students. n.量；数量

① It’s cheaper to buy goods in quantity / in large quantities. ② A large quantity of silk is sold in Japan. ③ A large quantity of drugs are found in his home. ④ Large quantities of rain are needed in this area. ① He tends to get angry when others disagree with her. ② His views tend towards the extreme（极端）. ③ He was tending (to) his son when I saw him in the hospital. ④ Jane is nice but has a tendency to talk too much. =Jane is nice but she tends to talk too much. ① The price of the new house in our area has gone up by 1,000 yuan per square meter（平方米）。That is（也就是说）it has gone up to 5,000 yuan per square meter. ② The wind has gone down a little. ④ The country has gone through too many wars.

初二物理平面镜成像知识点

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3、用垂直等距和光路图找物体的像。光路图的画法。画图中的实线和虚线： (1)实际光线用实线画，加箭头表示光线的行进方向; (2)反向延长线不是实际光线，所以用虚线画，不加箭头; (3)实像用实线画，虚像用虚线画，都要加箭头表示像的正倒; (4)法线等辅助线要用虚线画。 4、球面镜凹面镜：(1)作用：会聚光线(2)应用：太阳灶、汽车头灯凸面镜：(1)作用：发散光线(2)应用：汽车后视镜 5、虚像和实像虚像：非实际光线而是光线的反向沿长线会聚而成的像。实像：实际光线会聚而成的像叫实像。在光学中涉及到的像可分成实像和虚像。它们的共同点是都能被人眼观察到，即都有光线射入人眼。它们的不同点是：实像可以成在光屏上，如小孔成像，照像机成像、幻灯机成像均是实像;而平面镜成像，放大镜成像均是虚像。实像是光线的实际会聚而成，而虚像则是由发散的反射光线或折射光线的反向延长线会聚，形成虚像。 6、凸面镜和凹面镜 (1)用球面的外表面作为反射面的叫做凸面镜，用球面的内表面作为反射面的叫做凹面镜。 (2)凸面镜对光有发散作用，凹面镜对光有汇聚作用。 (3)凸面镜和凹面镜都遵循光的反射定律。 (4)凸面镜成缩小的像，能扩大视野范围。

高中英语《Unit4Globalwarming》课文语法填空新人教版

《Unit 4 Global warming》 Does It Matter? 一、语法填空(根据课文内容、依据语法规则完成下面短文） When 1________ (compare) with most natural changes, that the temperature of the earth rose about one degree Fahrenheit during the 20th century is quite shocking. And it’s human activity 2________ has caused this global warming rather 3________ a random but natural phenomenon. Dr. Janice Foster explains that we add huge 4________ of extra carbon dioxide into the atmosphere by burning fossil 5________. From the second 6________ and the discovery of Charles Keeling, all scientists believe that the burning of more and more fossil fuels 7________ (result) in the increase in carbon dioxide. Greenhouse gases continue to build up. On the one hand, Dr. Foster thinks that the trend would be a 8________. On the other hand, George Hambley 9________ (state) that more carbon dioxide would encourage a greater range of animals and bring us 10________ better life.

初二物理光学知识点梳理

初中光学 1．通过对学生观察\注意力的有效训练，促使学生集中精神学习，激发学生观察的主动性2．通过主动探究的学习，提高学生的独立\主动性，培养学生独立完成任务的意识 3．通过动力观察法，提升学生自我认知能力，引导学生掌握光学的方法及技巧

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2021学年八年级物理上册4.3平面镜成像知识点与考点解析人教版.docx

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Global warming全球变暖全英文介绍

One of the effects of global warming is the destruction of many important ecosystems.Changing and erratic climate conditions will put our ecosystems to the test, the increase in carbon dioxide will increase the problem. The evidence is clear that global warming and climate change affects physical and biological systems. There will be effects to land, water, and life. Already today, scientists are seeing the effects of global warming on coral reefs, many have been bleached and have died. This is due to warmer ocean waters, and to the fact that some species of plants and animals are simply migrating to better suited geographical regions where water temperatures are more suitable. Melting ice sheets are also making some animals migrate to better regions. This effects the ecosystems in which these plants and animals live. Several climate models have been made and they predict more floods (big floods), drought, wildfires, ocean acidification, and the eventual collapse of many ecosystems throughout the world both on land and at sea. There have been forecasts of things like famine, war, and social unrest, in our days ahead. These are the types of effects global warming could have on our planet. Another important effect that global warming will bring is the loss and endangerment of many species. Did you know that 30 percent of all plant and animal species alive in the world today are at risk of extinction by the year 2050 if average temperatures rise more than 2 to 11.5 degrees Fahrenheit. These mass extinctions will be due to a loss of habitat through desertification, deforestation, and ocean warming. Many plants and animals will also be affected by the inability to adapt to our climate warming.

globalwarming教案

Teaching Plan Contents: Reading Book 6 Unit 4 Global warming I.Analysis of the Teaching Material This article is from a magazine about global warming, which illustrates how global warming has come about and different attitudes to its effects. The passage is long, abstract and far away from their life. What’s more, there are many mouthful professional terms, which increases students’ difficulty while reading, although they have some knowledge about global warming. II. Analysis of the Students Students from Senior Two are the students in an excellent level, who have good abilities to read and speak. This unit talks about global warming, which has been taught in Geography. It will help students understand the text better and I believe the students will be interested in this class. However,because they pay little attention to this topic in the daily life, they may have few desire to speak something about global warming. III. Teaching objectives 1. Knowledge objective 1) Enable the students to analyze how global warming has come about； 2) Get students know different attitudes towards global warming and its effects. 2. Competence objective Improve the students’ reading and speaking abilities. 3. Emotion objective 1) Develop student s’ teamwork. 2) Raise their awareness of global warming. IV. Important points Enable the students to understand how global warming has come about. V. D ifficult points Get the students understand how global warming has come about. Let the students understand the difficult sentences better. ①It is human activity that has caused this global warming rather than a random but natural phenomenon. (Line 6) ②All scientists subscribe to the view that the increase in the earth’s temperature is due t o the burning of fossil fuels like coal, natural gas and oil to produce energy. (Line 18) ③This is when small amounts of gases in the atmosphere, like carbon dioxide, methane and water vapour, trap heat from the sun and therefore warm the earth.(Line 26-29) VI. Teaching aids: Multimedia classroom, printed material VII. Teaching methods: Task-based teaching, communicative teaching method VIII.Teaching procedures: Step 1. Lead in and pre-reading (5 mins ) It’s reported that global temperatures continue to rise, making July 2016 the hottest month in the history of the earth. Did you feel extremely hot in July? When you felt hot, what did you do? Did you feel global temperatures going up quietly? Let’s look at a flash (global temperatures from 1850 to 2016). What information can you get? The earth is becoming warmer and warmer. Is it natural or caused by human being? Do you think what effects global warming will bring about? Is global warming beneficial or harmful? Today we’re going to read a magazine article about global warming. It will work out your puzzles. Please open your book and turn to P26. Today we are going to

平面镜成像___知识点、经典例题、习题

课题平面镜成像教学目标了解并能描述平面镜成像特点；初步了解凸面镜和凹面镜及其应用；重点、难点平面镜成像特点教学内容一、知识点梳理复习 1、光的反射类型：镜面反射(光滑表面、反光、刺眼) 、漫反射（粗糙表面、各个方向）注：1、镜面反射和漫反射均遵循光的反射定律；2、光反射时，光路可逆，如下图。 2、平面镜成像特点实验名称：探究平面镜成像的特点. 实验目的：探究物与像到镜面的距离, 物、像的大小关系实验器材：两支大小形状相同的的蜡烛、一块玻璃板、玻璃板支架、一个光屏、一把直尺、一张纸和火柴. 实验步骤：参照如图2-3-1所示的步骤完成实验： (1)将玻璃板垂直架在纸上，在玻璃板前面立一支点燃的蜡烛，透过玻璃板观察其后面的蜡烛的像； (2)将另一未点燃的蜡烛放在玻璃板后，前后左右移动，直到看上去这支蜡烛与前面蜡烛的像重合，此时后面的蜡烛就代替等同于前面蜡烛的像，此时对比物与像的大小关系； (3)用直尺量出此时蜡烛和像到玻璃板的距离，并记录；

(4)改变燃着的蜡烛到玻璃板的距离，连做两次，分别观察蜡烛与像的大小关系，量出蜡烛与像到玻璃板的距离，分别记录下来； (5)将光屏放到像的位置，不透过玻璃板，直接观察光屏上有无像； (6)将玻璃板稍微倾斜一下，不再与桌面垂直，看一看像的变化，还能重合吗? (7)整理实验器材，结束实验. 实验结果：平面镜所成像的大小和物体的大小相等；像到平面镜的距离与物到平面镑的距离相等；平面镜成的是虚像，一句话概括：物与像关于镜面对称(距离相等、大小相等),成虚像. 实验存在的问题分析： (1)用玻璃板代替平面镜玻璃既能反光又能透光，用玻璃板代替平面镜是为了准确的找到像的位置,便于比较物与像的大小关系及测定物与像到镜面的距离. (2)实验时选用的玻璃板要薄些，如果用厚玻璃做这个实验，玻璃的两个表面都会发生反射，会看到两个不重合的像，不利于实验. (3)两只完全相同的蜡烛让没有点燃的蜡烛与像重合，这只蜡烛的位置也就是像的位置，这样做的目的是为了便于比较像和物的大小. (4)无论怎样移动物像都无法重合实验中使玻璃板与白纸垂直，否则，会出现玻璃板后的蜡烛无论怎样移动.都不能与前面蜡烛的像重合的现象(玻璃板倾斜时，像成在玻璃板的斜上方). 平面镜成像特点：（1）平面镜成的像和物体等大。（2）像和物到平面镜的距离相等。（3）像与物的连线与平面镜垂直。（4）平面镜成的是正立的虚像。（5）、平面镜的作用：（1）成像（2）改变光的传播方向（潜望镜） 5、虚像和实像虚像：非实际光线而是光线的反向沿长线会聚而成的像。实像：实际光线会聚而成的像叫实像。在光学中涉及到的像可分成实像和虚像。它们的共同点是都能被人眼观察到，即都有光线射入人眼。它们的不同点是：实像可以成在光屏上，如小孔成像，照像机成像、幻灯机成像均是实像；而平面镜成像，放大镜成像均是虚像。实像是光线的实际会聚而成，而虚像则是由发散的反射光线或折射光线的反向延长线会聚，形成虚像。 3、用垂直等距和光路图找物体的像。光路图的画法。

平面镜成像知识点的例题及其解析

平面镜成像知识点的例题及其解析【例题1】请利用平面镜成像的特点在图中作出AB物体在平面镜中的像，保留作图痕迹。答案如图所示：解析:先作出端点A、B关于平面镜的对称点A′、B′，用虚线连接A′、B′即为物体AB 的像，如图所示。【例题2】如图是验证“平面镜成像特点”的实验装置，其中A为玻璃板前点燃的蜡烛，B 为玻璃板后未点燃的蜡烛。有关本实验的说法错误的是（） A．玻璃板应该与桌面垂直 B．实验宜在较暗的环境中进行 C．眼睛应从B一侧观察成像情况 D．蜡烛燃烧较长时间后像物不再重合答案：C 解析：解答此题从以下知识点入手： ①实验中玻璃板如果不垂直于桌面，后面的蜡烛无法与前面蜡烛的像完全重合； ②眼睛在A的一侧观察。 ③物体射出的光线对人眼刺激越强，人眼感觉物体越亮，物体经过平面镜反射，反射光线进入人眼的光线越多，人眼感到物体的像越亮。在比较亮的环境中，很多物体射出光都对眼睛有刺激，干扰人的视线； ④平面镜成像特点之一：物像等大。 A.实验时玻璃板如果不竖直，不论怎样移动后面的蜡烛都不可能与前面蜡烛的像完全重合，就无法验证像的位置和大小，所以玻璃板应与水平桌面垂直放置。故A正确； B.在比较明亮的环境中，很多物体都在射出光线，干扰人的视线，在较黑暗的环境中，蜡烛是最亮的，蜡烛射向平面镜的光线最多，反射光线最多，进入人眼的光线最多，感觉蜡烛的像最亮。所以在比较黑暗的环境中进行实验，故B正确； C.寻找蜡烛A的像的位置时，眼睛应在蜡烛A一侧观察，在蜡烛B的一侧不能看到蜡烛A 的像；故C错误；

D.平面镜所成的像，物像等大，蜡烛燃烧较长时间后像物不再重合，故D正确。【例题3】小明身高1.6m，站在距平面镜3m处，能够看到自己的全身像。则他的像高m，像到平面镜的距离为m。答案：1.6；3 解析：根据平面镜成像的特点：①所成的像是虚像；②像和物体形状、大小相同； ③像和物体各对应点的连线与平面镜垂直；④像和物体到平面镜间距离相等来解答此题。（1）根据平面镜成像的特点，像和物体形状大小相同，所以身高1.6m的小明同学她在镜中的像高仍然为1.6m；（2）由平面镜成像的特点知，像和物体到平面镜间距离相等，当人到镜面的距离3m时，像到镜面的距离也为3m。【例题4】如图，A、B两地相距4km，MN是与AB连线平行的一条小河的河岸，AB到河岸的垂直距离为3km，小军要从A处走到河岸取水然后送到B处，他先沿着垂直于河岸的方向到D点取水，再沿直线DB到B处。若小军的速度大小恒为5km/h，不考虑取水停留的时间。（1）求小军完成这次取水和送水任务所需的时间。（2）为了找到一条最短的路线（即从A到河岸和从河岸到B的总路程最短），可以将MN看成一个平面镜，从A点作出一条光线经MN反射后恰能通过B点，请你证明入射点O即为最短路线的取水点。答案：（1）总路程 s=AD+DB=（3+5）km=8km 总时间 t=s/t=8/5h=1.6h （2）如图，根据平面镜成像的特点，作出A点关于MN所成的虚像A′连接A′D和A′O，AO=A′O，且A′、O、B在一条直线上，故取水点为O时的路线长度s=AO+OB=A′O+OB= A′B，在O点以外的河岸上任取一点P，路线的长度s′=AP+PB= A′P+PB 由三角形知识得A′B＜A′P+PB，即s＜s′ 故入射点O为最短路线的取水点。

2017_2018学年高中英语大题精做04Globalwarming含解析新人教版

Unit 4 Global warming I. 完形填空阅读下面短文，掌握其大意，然后从各小题所给的四个选项 (A、B、C和D) 中，选出最佳选项。 Today the scientific community is in almost total agreement that the earth’s climate is changing and that this represents a huge threat to the planet and to us. According to a survey, with only 69% accepting the earth is warming— only 1/4 Americans see global warming as a major threat, public opinion 1 the scientific conclusion. Climate scientists and campaigners have long debated how to better communicate the message to nonexperts so that climate science can be 2 into action. According to Christopher Rapley, the usual tactic(策略) of climate experts to provide the public wit h information isn’t 3 because ＂it does not address key potential causes.＂ We are all exposed to the evidence of climate change on an almost a daily basis. The information is almost 4 . Then what’s wrong? 5 our brains. Daniel Gilbert mentioned our brains’ failure to accu rately notice gradual change. Robert Gifford also __6__ the point about our brains’ difficulty in grasping climate change because of limited cognition and social __7__ with other people (＂Why should we change if X won’t?＂) .＂ A more powerful barrier is the 8 of perceived(感知的) be havioral control; ‘I’ m only one person; what can I do ?’ is certainly a big one.＂ For many, the first challenge will be in recognizing barriers 9 they can overcome them. But for those of us who understand that climate change is a problem yet make little effort to cut the number of overseas trips we make or the amount of meat we consume, neither the uncaring attitude nor denial really explains the 10 between our actions and beliefs. Lertzman has come to the conclusion that the conflict between __11 _ both the planet and our way of life is too painful to bear. ＂When we don’t 12 the pain of that, that’s when we get 13 and

高中英语《UnitGlobalwarming》阅读训练人教版选修

Global Warming Section A 本文词数:302 参考时间:2'40'' Rising temperatures in coming years would lead to less sea ice in the Southern Ocean that surrounds Antarctica and fewer habitats and feeding grounds for penguins, says the World Wildlife Fund (世界自然基金会) in its report 2 Degrees is Too Much. Antarctica and the Arctic are the most threatened regions from climate change. In the Antarctica, the temperature has risen 2.5 degrees in the past 50 years. This speed is nearly five times faster than that before the Industrial Revolution. It is mainly caused by burning fossil fuels. Unless nations reduce carbon dioxide emission1, the world will warm by an average of 2 degrees in less than 40 years. Rich nations should agree to reduce greenhouse gas emission. Temperatures near the Poles have risen much faster, which has led glaciers2 on the Antarctic Peninsula to melt3 quickly. The situation is quite critical, because in the past 50 years the number of emperor penguins (帝企鹅) has decreased by 50 percent across the whole Antarctica. On the Antarctic Peninsula’s northwest coast, the number of Adelie penguins (阿德里企鹅) has dropped surprisingly over the past 25 years. Fifty percent of the habitats of the emperor penguin and 75 percent of the habitats of the Adelie penguin face a rapid reduction, or even disappearance, if the global temperature rises 2 degrees above pre-industrial levels. With a 2-degree increase in global temperature and the decrease in sea ice thickness, emperor penguins will find it difficult to find new areas to live. With less sea ice, penguins could be pushed further south, but this could prevent them from hunting for food during the dark winters, because they need at least a few hours of daylight to find their food. Notes: 1. emission n. 排放 2. glacier n. 冰川 3. melt v. 融化词数:150处理时间:2′45″ Read the passage and then choose the best answer for each question. 1. The purpose of the passage is to _____. A. introduce readers to the Adelie penguins and emperor penguins B. tell readers about the rising temperatures in the Antarctica C. tell readers about the effect of global warming D. warn people that Antarctica is becoming smaller and smaller 2. In the writer’s opinion, what has caused global warming? A. That the earth is getting hotter and hotter. B. That the atmosphere of the earth is becoming thinner. C. That carbon dioxide emission is too high. D. That the use of oxygen in the air is out of control. 3. From the first paragraph, what do you think the author wants to tell us?