第一篇：英語演講 環境 溫室效應

The Greenhouse Effect

全球氣候變暖，是到目前為止對地球和人類生存最為緊迫也最為嚴重的威脅因素之一。

Global warming is one of the most urgent and the most serious factors now threaten Earth and human's survival 最近，全世界冰川融化速度創下歷史最快紀錄，從安第斯山脈到北極，冰川消融速度加快。全球氣候變暖將直接導致南、北極以及其它冰川融化，同時一些雪山也將隨著氣溫的不斷升高而消失。而融化后的冰川，將使海平面快速上升，世界很多美麗的城市終將被海水所淹沒。

Recently, The speed of melting glaciers set the record for the fastest, from the Andes to the Arctic glaciers melting faster.Global warming will lead directly to melting of the Antarctic, the Arctic and other glaciers, Meanwhile, some snow-capped mountains will disappear with temperatures rise.The glaciers melted will enable the sea level to rise rapidly, many beautiful cities in the world will eventually be submerged.100年后 南極只曾留下回憶

years later, the Antarctic had left only memories 氣溫升高，全球變暖，極地冰川融化，企鵝失去家園！

Higher temperatures makes global warming and Melting of polar ice, so the penguins lose their homes!30年后的夏季，北極可能是一片汪洋

Summer after 30 years, the Arctic may be an ocean.乞力馬扎羅山的“雪帽”將在15年內被摘掉

Kilimanjaro “snow cap” will be taken off in 15 years.乞力馬扎羅山是非洲最高的山脈，它距離赤道僅僅300多公里，頂部卻終年滿布冰雪。但是，全球變暖導致這座山的終年積雪不斷消融，專家預言，“雪帽”將在15年內被摘掉。

Kilimanjaro is the highest mountain in Africa, it is just over 300 km from the equator, but the top covered with snow all year round.However, Global warming leads to the mountain snow continue to melt, experts predict, “snow cap” will be taken off in 15 years.什么造成了溫室效應? What causes the greenhouse effect? 我認為主要有兩個原因：人類排放二氧化碳和砍伐樹木

I think there are two main reasons: human emissions of carbon dioxide and cuts down trees.人類每秒鐘釋放的二氧化碳已經超過700噸，一年就是230億噸

Carbon dioxide released by humans every second has more than 700 tons ,a year is 23 billion tons.亞馬孫河流域的農民正在焚燒熱帶雨林，以開墾更多耕地。每分鐘，全世界清除掉的熱帶森林的面積，相當于200個足球場的大小。依照現在的這種破壞速度，亞馬孫雨林將在400年以內完全消失。Amazonian farmers are burning rainforest to reclaim more land.Every minute, The world's tropical forests cleared an area equivalent to the size of 200 football fields.According to the current rate of this destruction , The Amazon rainforest will completely disappear within 400 years.我們依靠在地球上的一切，我們需要生存，所以讓我們照顧它。We rely on the Earth for everything, we need to survive, so let’s take care of it.

第二篇：大學生英語演講環境

hello everyone, today i want to give a speech about our environment.as we know , we have a beautiful world.we can see the sun shining.we can see the moon in a full view.we can see the birds flying in the sky.we can see the horses running on the plain.however, the world is not as beautiful as before, for human beings have brought a disaster to the world.so there are many environment problems in our life, for instance, white pollution, global warming, and desertification.all of us know that the earth is our home, but many of us are destroying the earth.as the time pass, maybe we will face to the problem, which more serious and severe.my major is environment engineering.since i entered the campus, my teacher asks me a question, “why you choose this major?” alough this major isn’t my first choose, but i think maybe i be a member in protect our environment in future.we only have one world, we must do something to this word.by saying so, i do not mean we should give a sudden stop to any development.because that will result in a threat to the existence of human society.i mean we should treat nature equally, find a harmony between earth and people.leaving the chance of existence and development to nature as we are obtaining the same thing, and thus we will get the situation of win-win.i am looking forward that environment can be better and better in our protection.that’s all.thank you!篇二：大學生英語演講文章20篇(英漢對照版)大學生英語演講稿i believe in our future

六、周怡雪，19歲，上海 i believe in our future honorable judges, fellow students: good afternoon!recently, ther is a heated debate in our society.the college students are the beneficiaries of a rare privilege, who receive exceptional education at extraordinary places.but will we be able to face the challenge and support ourselves against all odds? will we be able to better the lives of others? will we be able to accept the responsibility of building the future of our country? the cynics say we care for nothing other than grades;and we neglect the need for character cultivation.but again, the cynics are wrong.we care deeply for each other, we cherish freedom, we treasure justice, and we seek truth.last week, thousands of my fellow students had their blood type tested in order to make a contribution for the children who suffer from blood cancer.as college students, we are adolescents at the critical turning point in our lives.we all face a fundamental choice: cynicism or faith, each will profoundly impact our future, or even the future of our country.i believe in all my fellow classmates.though we are still inexperienced and even a little bit childish.i believe that we have the courage and faith to meet any challenge and take on our responsibilities.we are preparing to assume new responsibilities and tasks, and to use the education we have received to make our world a better place.i believe in our future.我對未來充滿信心

尊敬的評委，各位同學： 下午好！

最近，社會上有一場很激烈的爭論。大學生是一種稀有特權的享有者，在很棒的地方接受高等教育。但是，我們能面對挑戰而無所畏懼嗎？我們能夠改善他人的生活嗎？我們能夠承擔建設祖國未來的重任嗎？

懷疑論者說大學生是被寵壞的一代，一丁點挫折都受不了。但是他們錯了，我所看到的大學生正在努力的學習獨立生活。我們互相幫助打掃衛生，一起上街砍價購物，一起參加兼職工作來賺零花錢。

懷疑論者說我們除了成績什么都不關心，從而忽略了性格的培養。但是，他們又錯了。我們彼此關心，我們向往自由，我們珍惜公正，我們追求真理。上個星期，很多我的同學去驗血，為了給患血癌的孩子貢獻自己的力量。

作為大學生，我們是處在人生分水嶺的青年。我們都面臨一個重要的選擇：懷疑人生還是相信自己，每一種都會給我們的人生帶來重大的影響，甚至影響我們祖國的未來。我相信我們的同學們，雖然我們依然缺乏經驗，甚至有些志氣，但是我相信我們有勇氣和自信來面對生活的挑戰并承擔我們的責任。我們正努力準備接受新的任務，用我們所學習的知識將世界變得更美好。我對我們的未來充滿信心。

大學生英語演講稿17 change the ingredients of your life

十七、王晨，20歲，安徽

change the ingredients of your life if kindness is added to a strange you will have a friend;but if hostility is added, you will have an enemy.if love is added to a pile of red bricks you will have a home, but if hatred is add to those bricks , you will have an concentration camp.three year ago, i weighed more than 100 hundred kilograms which caused significant embarrassment and frustration in my life.like always failing my p.e examinations, like always being laughed at by girls, like being terrified to speak in public.it was my gr so my dear friend, if faith, hope, love, endurance are added to your life, you will find the confidence to conquer your limitation and embrace new challenges.and hopefully with my speech included, you will have a fantastic speech contest.改變生活的味道

這是一杯白開水，平淡無味，對吧？可是加上點糖呢，他嘗起來會有甜味；如果加的是蘇打水，味道就會變苦。人生同樣如此——個中滋味在于我們的選擇。

善待他人，你會擁有朋友；但如果充滿惡意，則會多個敵人。將愛賦予一堆紅磚，你會擁有一個家；用仇恨來澆鑄這堆紅磚，就會鑄成一座集中營。

因此親愛的朋友們，不要抱怨人生乏味，世間無望。不喜歡生活的味道，那就換一換生活的調料吧！

三年前，我重達100多公斤，這給我帶來了很多尷尬和挫折：體育課老是不及格，總被女孩們嘲笑，更不敢當眾發表意見。幸而由于祖母的鼓勵，我不在消極人生，而是充滿自信。她曾經說過：―孩子，如果體形無法改變，為什么不把它看做自己獨特的風格呢？‖ 我開始這樣來審視人生，通過改變生活的視角，我信心大增地去改變我的人生，很快就發現一個嶄新的世界。

朋友們，將信念，希望，愛意和忍性溶入生命，你就會找到自信，克服缺點，迎接人生新的挑戰。最后我的演講包括在內，希望你會看到一場精彩的演講比賽。大學生英語演講稿16

十六、楊穎，21歲，海南 kipling said:―east is east, and west is west, and never the twain shall meet!‖

but now, a century later, they have met.when two cultures meet, there may be things in one culture, which do not fit into the tradition of the other.when this happens, we need to learn to understand and respect the customs of another culture.then there are certain things some people may not like.to this, i will say, if you do not like it, please try to tolerate it.to learn to tolerate what you personally don‘t like is a great virtue at a time when different cultures mix and merge.before us, there are two rivers, eastern and western cultures.at present, they may run in different courses.but eventually, they will converge into the vast sea of human culture.right now, i can see peoples of eastern and western cultures, standing side by side, singing the olympic theme song: we are hand in hand, heart to heart, together we will shape a beautiful tomorrow!thank you!讓我們共同感受東西方的融合吉卜林說過:東方是東方，西方是西方，二者永不相聚。但是一個世紀后的今天，東西方相匯了!它們相聚在經濟領域，它們相聚在教育領域，它們相聚在藝術的殿堂。有人爭論說:這種融合需要我們在東方和西方之間做出選擇，但我卻堅信最美好的未來在于東方和西方創造性的融合。我們可以將西方的思想，觀念和技術變為我們自己所用的東西。

我喜愛京劇和河南豫劇，因為它們經常使我想起自己是誰。但我也熱衷于流行音樂，特別是英文歌曲。于是我將東方的旋律和西方的語言結合到了一起，它叫做西方版的河南豫劇。

當兩種文化相結合的時候，也許一方的文化中的某些東西不適應另一方的傳統文化。當此種情況出現時，我們需要試著理解并接受另一種文化中的風俗習慣。然而，也許有些東

西你并不喜歡，對于此，我可以說，如果你不喜歡它，請試著去容忍它。當兩種文化融合的時候，試著去容忍你個人不喜歡的東西是一種美德。在我們面前有兩條河流，東方文化和西方文化。現在，它們也許正朝著不同的方向流去。但是最終它們將匯合到人類文化的海洋里。

就在此時此刻，我看見東方和西方的人肩并肩的站在一起，高唱奧林匹克主題曲:我們手拉手，心靠著心，共同創造美好的明天!大學生英語演講稿英語風采大賽半決賽選手自備演講賞析(大學成人組)

十五、黃揚，21，福建 farewell, indifference who was the most well-known figure in china last month? it‘s ma jiajue—the college student who murdered 4 of his roommates.many people attributed his crime to his poverty and deficient education.in my opinion, his crime also has much to do with his classmates‘ indifference.indifference is a terrible disease in today‘s colleges and the whole society.it‘s not rare that two students who have studied together for 4 years have never spoken to each other.it‘s not rare that a student who has been absent from class for several days is not noticed at all.it‘s also not rare that a student who has severe psychological problems is not cared about at all.some people may say ?what the students with psychological problems like ma jiajue need is not care but psychotherapy.‖ however, when people are ill, what they need most is not only medical treatment, but also care from people around them.every smile and every caring word will bring sunshine to their life.what can we do to prevent the tragedy of ma jiajue from happening again? some people may say ?let‘s open more psychological courses in schools.‘ and other people m篇三：大學生三分鐘英語演講

大學生三分鐘英語演講 a serious problem has arisen in recent several years that more and more college students abandon study because of their taking part-time jobs, so quite a few people are opposed to part-time jobs.however, taking part-time jobs has at least three benefits for college studens in my eyes.first, students can promote their study through part-time jobs.for instance, if a law student finds a part-time job in a law firm, his practice will enable him to better understand what hes learned from books.whats more, the part-time job can offer him opportunities to go beyond what hes been taught in class, and hell learn something that doesnt exist in books but in practice.second, students can also accumulate work experiences through part-time jobs, which will benefit their future job-hunting.actually, part-time jobs act as warm-up exercises for students to take full-time jobs after they graduate, and help them prepare for their future careers.in addition, as fresh blood in the society, graduated students are often unfavored in job-hunting markets for lack of practical work experiences.its easier to find jobs for those who have accumulated experiences in part-time jobs.大學生英語演講稿i believe in our future

六、周怡雪，19歲，上海 i believe in our future honorable judges, fellow students: good afternoon!recently, ther is a heated debate in our society.the college students are the beneficiaries of a rare privilege, who receive exceptional education at extraordinary places.but will we be able to face the challenge and support ourselves against all odds? will we be able to better the lives of others? will we be able to accept the responsibility of building the future of our country? the cynics say we care for nothing other than grades;and we neglect the need for character cultivation.but again, the cynics are wrong.we care deeply for each other, we cherish freedom, we treasure justice, and we seek truth.as college students, we are adolescents at the critical turning point in our lives.we all face a fundamental choice: cynicism or faith, each will profoundly impact our future, or even the future of our country.i believe in all my fellow classmates.though we are still inexperienced and even a little bit childish.i believe that we have the courage and faith to meet any challenge and take on our responsibilities.we are preparing to assume new responsibilities and tasks, and to use the education we have received to make our world a better place.i believe in our future.我對未來充滿信心

尊敬的評委，各位同學：

下午好！

最近，社會上有一場很激烈的爭論。大學生是一種稀有特權的享有者，在很棒的地方接受高等教育。但是，我們能面對挑戰而無所畏懼嗎？我們能夠改善他人的生活嗎？我們能夠承擔建設祖國未來的重任嗎？

懷疑論者說大學生是被寵壞的一代，一丁點挫折都受不了。但是他們錯了，我所看到的大學生正在努力的學習獨立生活。我們互相幫助打掃衛生，一起上街砍價購物，一起參加兼職工作來賺零花錢。

懷疑論者說我們除了成績什么都不關心，從而忽略了性格的培養。但是，他們又錯了。我們彼此關心，我們向往自由，我們珍惜公正，我們追求真理。

作為大學生，我們是處在人生分水嶺的青年。我們都面臨一個重要的選擇：懷疑人生還是相信自己，每一種都會給我們的人生帶來重大的影響，甚至影響我們祖國的未來。我相信我們的同學們，雖然我們依然缺乏經驗，甚至有些志氣，但是我相信我們有勇氣和自信來面對生活的挑戰并承擔我們的責任。我們正努力準備接受新的任務，用我們所學習的知識將世界變得更美好。我對我們的未來充滿信心。

大學生英語演講稿13 hold fast to your dreams

十三、張晶晶，21歲，山西 hold fast to your dreams i have a dream today.i have a dream that one day every vally shall be exalted, every hill and mountain shall be made low, the rough places will be made plain, and the crooked places will be made straight, and the glory of the lord shall be revealed, and all flesh shall see it together.wow, what a dream it has been for martin luther king.but the changing world seems telling me that people gradually get their dreams lost somehow in the process of growing up, and sometimes i personally find myself saying goodbye unconsciously to those distant childhood dreams.however, we meed dreams.they nourish our spirit;they represent possibility even when we are dragged down by reality.they keep us going.most successful people are dreamers as well as ordinary people who are not afraid to think big and dare to be great.when we were little kids, we all dreamed of doing something big and splashy, something significant.now what we need to do is to maintain them, refresh them and turn them into reality.however, the toughest part is that we often have no ideas how to translate these dreams into actions.well, just start with concrete objectives and stick to it.don’t let the nameless fear confuse the eye and confound our strong belief of future.through our talents, through our wits, through our endurance and through our creativity, we will make it.hold fast to dreams, for if dreams die, life is a broken-winged bird that cannot fly.hold fast to dreams, for when dreams go, life is a barren field frozen with snow.so my dear friends, think of your old and maybe dead dreams.whatever it is, pick it up and make it alive from today.抓牢你的夢想

我今天有一個夢想。

我夢想有一天，幽谷上升，高山下降，崎嶇之地變平原，曲折之路成坦途。圣光展露，滿照人間。

這對馬丁路德金是怎樣的一個夢想啊。不過這個變化著的世界似乎在告訴我，在成長的過程中，人們卻不知不覺把他們的夢想弄丟了，而我自己也有時會覺得在告別很多童年的夢。然而，我們是需要夢想的。夢想滋養我們的靈魂，夢想代表著我們被現實拉垮時依然具有的希望。它鼓勵我們不斷前進。大多數成功人士都是夢想家，同時也是普通人，只是他們敢于夢想敢于成就偉大。當我們還是孩子的時候，我們都夢想過做一番大事業，現在應當做的就是保存好那些夢想，再度恢復它們，并將它們實現。不過最難的是我們通常不知道怎樣付諸實施。那么，就從最具體的目標開始，堅持去做吧。不要讓那些莫名的恐懼迷惑了我們的雙眼，影響了我們對未來的信念。用我們的天資和智慧，用我們的耐力和創造力，我們一定會實現夢想。

抓牢你的夢想，因為如果夢想死亡，生活就成了一只折斷翅膀的鳥再也不能飛翔。抓牢你的夢想，因為如果失去夢想，生命就成了一塊覆蓋著冰雪的貧瘠的凍土。親愛的朋友

們，想想那些過去的或已經死去的夢想吧。不管是什么，重新將它撿起，并從今天開始讓它重生。

大學生英語演講稿12 make every moment count

十二、劉懿，21歲，重慶 make every moment count it is the same with filling the jar.even if you place a dozen fist-sized rocks and a bucket of gravel into the jar, there is still space for sand and water between the rocks and gravel.time is the most valuable of all our possessions, but the most perishable as well.as henry david thoreau said,＂you must live in the present, launch yourself on every wave, find your eternity in each moment.＂ whenever i fell the lack of time in the future, i will tell myself ＂carpe diem , seize the day, make every moment count.＂

抓住每分每秒 星沙英語網

有天晚上，我向媽媽抱怨自己事情太多，時間不夠。她說道：“你抱怨沒有時間就是因為你把珍貴的分分秒秒都浪費在抱怨和焦慮上。關鍵是，無論你的時間表排得多滿，如果你真的努力嘗試了，你還是總能間插地做些事情。”

這同填充廣口瓶是一個道理，即使你將一小堆拳頭大小的石塊和一桶碎石倒進瓶里，也還能繼續倒入沙子和水，使其漏進石塊的間隙中去。

“沒時間”無異于我為自己浪費分分秒秒找的托詞罷了。我相信成功與失敗的一線之差可以用六個字來形容：“我沒足夠時間。” 然而事實上，我卻與海倫．凱勒，帕斯特，杰弗遜和愛因斯坦每天所擁有的時間分秒不差。關鍵是我并未觸及生命的真諦：抓住，享受生命的每一分鐘。不要碌碌無為，不要耽擱推遲，不要牢騷抱怨！往往是在我抱怨和遲疑的時候，我的命運就被決定了。而一旦我能善用分分秒秒，我相信我的煩惱也會被逐漸瓦解。

在我們所擁有的財富中，時間是最珍貴而又最不持久的。正如梭羅所說的那樣：“你得抓住現在，把握機會，在短暫的瞬間中尋找永恒。”

如果將來我再發覺沒時間的時候，我會告誡自己，“carpe diem(拉丁語)，抓住今天，抓住每分每秒。

第三篇：關于環境的英語演講

Dear teacher and my dear friends: I am very pleased to stand here and deliver a short speech to you.And I feel quite lucky to be the first oneto give the speech.Today my topic is about our environment.Environmental problems are becoming more and more serious all over the world.With the development of industry and agriculture, cars make great noise and give off poisonous gas.Trees on the hills have been cut down,and waste water is being poured continuously into rivers.Furthermore,wherever we go today, we can find rubbish carelessly disposed.The whole ecological balance of the earth is changing.The earth is our home and we have the duty to take care of it for ourselves and for our later generations.Sohow to protect the environment? Initially,We must face the situation that exists and take actions to solve our environmental problems.For instance, new laws must be passed to control industrial pollution, the public must receive the education about the disadvantages of pollution and so on.We hope that all these measures will be effective and bring back a healthful environment.As for us, as school students, can also join in recycling activities to protect the environment.For example, set up a recycling center beside, which is very useful.It is used to collect the waste paper and plastic bottles.In the high school, our classmates used to throw all of these into the trashbin.At the very beginning of this collecting activity, it was not so warm-welcomed.Later, more and more people were influenced by the others and joined this collecting activity.Gradually, all the students in our class form a good habit to protect the environment.All of us will now put away the reusable things instead of throwing them into the trashcan.We should always remember in our mind that protecting the environment is our duty that we can never neglect.Finally would you please let me end this speech with a little poem, “Be kind to the river.Be good to the trees.Smile at the sunshine, and bow to the breeze.Be friendly to nature, and nature will be friendly to you!”

第四篇：environment,環境,英語演講

開場白：Morning, everyone.Today I will share something about the environment with you.1、Look at this picture.Does it remind you of anything? You see that river, gently flowing by;you notice the leaves, rusting with the wind;you hear the birds;you hear the frogs;in the distance, you hear a cow, you feel the grass, the mud gives a little bit on the river bank.It‘s quiet, it‘s peaceful.And all of a sudden, it’s a great shift inside you, and it’s like taking a deep breath and going,(深吸一口氣)oh, yeah, I almost forgot about this.2、This is a picture of the earth from space that any of us ever saw;it was taken on Christmas Eve, 1968, during the Apollo8 mission.We can see the earth within relatively comfortable boundaries.But we are filling up that thin shell of atmosphere with pollution.3、This is the central park of Bit.I took it by myself on November, 1, 2013.On the picture, we see the whole park is covered with heavily thick smog.It was right on that evening, I had been playing the badminton outside with my friends for three solid hours.Thank god, I’m still alive.Do you feel a little frustrated just the same as me? Yes, we are always missing something only when we do not own it anymore.4、It comes to me another well-known wisdom that what gets us into trouble is not what we don’t know;it’s what we know for sure that just ain’t so.----Mark TwainThis is actually an important point believe it or not, because there is an assumption that a lot of people have in their mind right now about the air pollution.They just think so, the assumption sounds like this, the earth is so big, we can’t possibly have any lasting harmful impact on the earth environment.Maybe that was true at one time, but it’s not anymore.And one of the reasons it is not true anymore is that the most vulnerable part of the earth ecological system is the atmosphere.Vulnerable, because it’s so thin.That is to say, anything what we had done can truly make a big difference to the environment.This is meant to be the end but we won’t end it here.5、It’s so lucky for me that I toke this picture at the right same spot after I finished the preparation for today’s presentation.You see the blue sky;and the central park is filled up with warm sunshine and fresh air.Sometimes you feel some soft wind from nowhere.（放出第二張圖片）Is it not beautiful?

結束語：thank you for listening.

第五篇：溫室效應教案

化學與生活 第一單元 空氣質量的改善

第二課時 溫室效應

一、教學設計思路

“以學生發展為本”作為指導思想，以貼近生活實際的污染大氣環境實例為素材，以科學探究學習活動為主線，遵循學生的認知規律，按照“知地—明理—說理—析事”的序列設計問題，提高學生獲取、加工、應用信息的水平，培養學生探究性學習和創新學習的能力及團體合作意識，增強學習的興趣。

二、教學目標

1.知識與技能：了解溫室氣體的種類，導致全球氣候變暖的原因、危害及防治措施。2.過程與方法：聯系實際，調查當地大氣污染狀況，提出防治措施，培養學生自主探究學習的能力。

3.情感態度與價值觀：認識環保的意義，樹立科學的環境觀念、全球觀念和可持續發展觀念。

三、教學重點、難點：

溫室效應的危害，如何有效地控制溫室效應的產生

四、教學方法：討論法： 自主閱讀、分組討論

五、教學課時：1課時

六、教學過程

【創設情景導入】 1982年冬天，美國紐約出現22度高溫，創百年記錄；1987年夏天，希臘雅典出現罕見持續46度高溫天氣；1988年7月中國武漢高溫天氣持續25天之久。【提問】這個材料反映了什么問題？ 學生回答：全球氣候變暖。

【過渡】全球氣候變暖是由溫室效應引起的。今天我們就一起重點來研究溫室效應的危害，如何有效地控制溫室效應的產生。【板書】溫室效應

1、溫室效應的原理

【講述】大氣中的二氧化碳濃度增加，阻止地球熱量的散失，使地球發生可感覺到的氣溫升高，這就是有名的“溫室效應”。破壞大氣層與地面間紅外線輻射正常關系，吸收地球釋放出來的紅外線輻射，就像“溫室”一樣，促使地球氣溫升高的氣體稱為“溫室氣體”。二氧化碳是數量最多的溫室氣體，約占大氣總容量的0.03%，許多其它痕量氣體也會產生溫室效應，其中有的溫室效應比二氧化碳還強。

【講述】我們可以通過一個演示實驗來模擬大氣中的溫室效應，請大家閱讀教材第4頁的“觀察與思考”欄目。

【活動與探究】在兩個錐形瓶中分別充入CO2和空氣，用帶溫度計的單孔橡皮塞塞住瓶口。把它們并排放在實驗桌上，底部各放一塊黑紙板。用100W的燈泡均勻地照射，觀察現象并解釋原因。

【現象】充入二氧化碳的瓶中溫度上升較多。

【解釋】由于二氧化碳的存在，使錐形瓶內吸收的熱能與散發的熱能之比大于另一支錐形瓶內吸收的熱能與散發的熱能之比，導致盛二氧化碳的錐形瓶內溫度升高。【提問】那么引起溫室效應的氣體主要有哪些呢？ 【板書】

2、主要的溫室氣體

學生閱讀討論回答：二氧化碳、甲烷、水蒸氣等。(二氧化碳的含量最多)【材料】據有關資料記載，二氧化碳正以每年0.4％的增長率在增加，科學家預測，到2050年大氣中二氧化碳濃度將增加1倍，全球平均氣溫將上升1.5－4.5度。觀測表明，近百年來全球海平面已經上升了10～20厘米。

【提問】為什么二氧化碳的含量在不斷的增加呢？ 學生分組討論： 自然原因

人為原因：

1、燃燒大量的煤、石油等礦物燃料，向大氣中排放大量二氧化碳；

2、亂砍濫伐導致森林面積急劇減少，特別是對熱帶雨林的破壞。

【過渡】由此可見，大氣中二氧化碳含量的增多導致了大氣的保溫效應，大氣的保溫的效應導致了全球氣候變暖。氣候變暖給人類和社會帶來的影響是利弊參雜，但總的來說是弊大于利。

【提問】溫室效應的加劇會給人類帶來什么樣的危害？ 【板書】

3、溫室效應的危害 【學生討論，歸納小結】： 它會帶來以下列幾種嚴重惡果：

（1)地球上的病蟲害增加；

（2)海平面上升；

（3)氣候反常，海洋風暴增多；

（4)土地干旱，沙漠化面積增大。

【介紹】科學家預測：如果地球表面溫度的升高按現在的速度繼續發展，到2050年全球溫度將上升2－4攝氏度，南北極地冰山將大幅度融化，導致海平面大大上升，一些島嶼國家和沿海城市將淹于水中，其中包括幾個著名的國際大城市：紐約，上海，東京和悉尼。【思考討論】全球變暖弊大于利，為緩解目前狀況，你有哪些錦囊妙計呢？

【學生討論交流、回答】為減少大氣中過多的二氧化碳，一方面需要人們盡量節約用電（因為發電燒煤），少開汽車。另一方面保護好森林和海洋，比如不亂砍濫伐森林，不讓海洋收到污染以保護浮游生物的生存。我們還可以通過植樹造林，減少使用一次性方便木筷，節約紙張（造紙用木材），不踐踏草坪等等行動來保護綠色植物，使它們多吸收二氧化碳來幫助減緩溫室效應。

【總結】通過共同交流，同學們都獻計獻策，共同保護我們的家園，爭做“綠色家園”的環保衛士，精神可佳可賀，但愿能積極投入于行動。6月5日已成為“世界環境保護日”，這足以說明國際社會已達成共識，聯起手來共同保護我們的“綠色家園”。【板書】防治措施：1.提高能源的利用效率，采用新能源

2.加強國際間的合作，減少二氧化碳的排放量 【課堂鞏固】

1、導致二氧化碳增多的原因是（）A、制冷工業

B、森林遭破壞 C、大量使用礦物能源

D、新能源的使用

2、下列敘述，正確的是（）

A、全球變暖，會使降水增加，農作物增產 B、保護大氣環境，需要獨立努力

C、保護熱帶雨林，是減少CO2含量的有效措施 D、我國遠離南極，可不參與臭氧層保護

【課堂小結】通過今天的學習，我們了解了由于人類活動導致了全球氣候變暖，氣候變暖給人類和社會帶來很大的危害。為了保護我們的“綠色家園”也為了我們自己，讓我們攜起手來，從現在做起，從自我做起，從身邊的小事做起，為保護環境做一些我們力所能及的事情！【布置作業】作業本 【板書設計】 溫室效應

1、溫室效應的原理

2、主要的溫室氣體

3、溫室效應的危害

4、溫室效應的防治措施 【教學反思】

本節課主要介紹了溫室效應的危害和防治措施，內容較簡單，所以引導學生閱讀教材，自主去發現教學內容，明確目標任務，能有效激發學生的學習動機；創設問題情景，再通過討論、自主閱讀等方式引導學生分析問題、解決問題。通過學生分組討論，讓學生認識到環保的意義，自覺樹立環保的意識。

湖州一中生化組 王費華