小学+初中+高中+努力=大学

Unit 4 Global Warming

一、 教学对象分析

本校学生学习自主能力较强，善于思考，认真笔记。喜欢课堂环节紧凑、有序、充实学习方式，但在英语口语表达能力方面还有待提高。本课探讨全球气候变暖话题，学生在生活体验和地理知识方面，有一定的积累和初步的认知，但对于全球变暖的实质与影响了解得还不是特别清楚，有必要通过科普文教学进行探讨，增强责任意识，共同努力保护我们共同的家园。 二、 教材内容分析 〈人教版〉模块六第四单元Reading部分是一篇杂志文章，主要讲述了地球温度上升的现象和原因。20世纪中，地球的温度上升了华氏1度。这看上去是一个很小的数字，但相对于在自然界的其他现象来说，这个增长速度是迅猛的。这种现象是自然发生的还是人为的？这个问题引起了激烈的争论。许多科学家认为，这种变化是人类燃烧矿物所致。这些物质的燃烧产生以二氧化碳为主的温室气体。正因为自然界有温室气体的存在，地球才不至于很冷。但大量排放二氧化碳会使地球普遍升温。对于地球升温，科学家有不同的看法。有些科学家认为，这个问题很严重。地球升温会导致海水上涨、风暴、干旱、饥荒、物种灭绝和疫病等。也有科学家认为，地球升温有利于改善人类生活，比如，庄稼长得更快、产量更高等。文章最后以开放性的问题结尾要求读者思考：对于全球变暖，人类要不要采取措施？ 三、 教学目标

（1）分析全球气候变暖产生的原因

（2）了解科学家对于全球变暖的不同看法。 四、 教学过程

Step 1 Warming-up and lead-in (5 mins) （1）视频导入

教师选用一小段关于北极熊的视频，让学生带着问题观看视频，并由此导入到本课的课题。 T: Hello, class. First of all, Let’s watch a short video about a polar bear and please find out what happened to the polar bear.

① What happened to the polar bear? (It was drowned.) ② Why was it drowned? ( Because the ice melt.)

③ Why did the ice melt? （ Because the earth is becoming warmer.） （2）揭题

[意图说明]教师希望通过视频导入的方式能够让学生马上进入状态，注意力集中，并对本课话题Global Warming这种相对枯燥难理解的科普文产生浓厚的兴趣。 Step 2 Reading （30 mins）

（1） 根据所给的分段大意，让学生通读全文进行分段，并匹配正确的四部分大意。此环

节旨在让学生了解文章的篇章结构，并突出本课时重点解决的两大部分。

T ：Go through the whole text in 5 minutes and divide it into 4 parts according to the main idea of each part.

（2） 阅读第一段 找出谁写了这篇杂志文章，并在文章探究什么问题。

T：This is a magazine article. Read Para.1 second line and find out who wrote the magazine article. (Sophie Armstrong )\\ T: What questions does she explore in the article? ( ① How has this global warming come about? ② Does it matter? )

（3） 齐读第二段找出第一个问题的答案，并给予解释，让学生对这个长难句有清晰的理

解。增强他们学习科普文的信心。 小学+初中+高中+努力=大学

小学+初中+高中+努力=大学

T： First, let’s explore the question how this global warming has come about? （ It’s human activity that has caused this global warming rather than random but natural phenomenon.）

T: What’s the meaning of this sentence? ( 全球变暖是人类活动导致的，而不是随意的自然现象。)

T：How has human activity caused this global warming? Do you want to know? Today we”ll explore it. （4） 读两张图表，获取基本信息，并分析图表之间的联系，让学生进一步理解课文内容。

培养学生读取并分析图表的能力，提高阅读科普文的能力。

T: Have you noticed the two graphs on Page26? Let’s read the two graphs together. First, what are they about? ( Graph1: Temperature difference from long-term average,1860-2000 Graph2: Carbon dioxide content in the atmosphere, 1957-1997) T: Pay attention to the time of the two graphs. It’s clear that the period of Graph1 is longer than that of Graph2. Can we do divide Graph1 into 2 parts. The first period is before 1957. The second period is after 1957. Comparing the two parts, we know the temperature went up more rapidly. T: Now, turn to Graph2. From 1957-1997 the carbon dioxide in the atmosphere increased from about 315 parts to about 370 parts per million. It increased greatly, too. So look at the same years of temperature, compared to the years of CO2, you can see, they both went up rapidly. Can you find some relationship between them？（ The more CO2, the higher temperature.）

（5） 通过将第三段分解阅读，降低科普文阅读难度，帮助学生更好地理解全球变暖，温

室效应，温室气体等专业术语的理解，并进一步解决本课难点。

T : ①Why does more CO2 cause higher temperature?

②Have you learnt something from your Geography teacher? Will you share it with us? If you have difficulty in speaking in English, you can try it in Chinese. ( 温室气体，温室效应…….)

③What is greenhouse effect? Para3 Line24-36 will help you. ( Greenhouse gases trap the heat of the sun and therefore warm the earth. It is known as greenhouse effect.)

④ What are greenhouse gases? ( Gases like carbon dioxide, methane and water

vapour)

⑤ Is “greenhouse effect” beneficial or harmful to us? ( It is harmful.) ⑥ Why? ( The earth is becoming warmer and warmer.)

⑦ Without the greenhouse effect, what would the earth be like?( It would be

thirty-three degree Celsius cooler than it is.)

⑧ T: So we need the greenhouse gases. They do good to us. However, when we

add huge quantities of extra carbon dioxide into the atmosphere. What will happen? ( More heat energy tends to be trapped in the atmosphere causing the global temperature to go up.)

⑨ Why is extra carbon dioxide added into the atmosphere? Read Para3 Line18-23

and Para.5, and you will find the answer. （ It is the burning of more and more fossil fuels that has resulted in this increase in carbon dioxide. The increase in carbon dioxide resulted in the increase in the earth’s 小学+初中+高中+努力=大学

小学+初中+高中+努力=大学

temperature.）

（6） 阅读第六段，解决本课的第二个重点知识，对于全球气候变暖所造成的后果的两种

截然不同的观点。

① Is “global warming” beneficial or harmful to us? Or does it matter? Para6

lists two different attitudes, please find out what attitudes they take? ( Dr. Foster says: “ An increase of five degrees would be a catastrophe and serious. Scientists like George Hambley are opposed to the view and believe we should not worry about high levels of carbon dioxide in the air. More carbon dioxide is a positive thing.)

② Is it clear that what effects of global warming will be? (No. No one knows

the effects of global warming.)

③ Does it mean we should do nothing? We are not sure now. We’ll leave it to

the next class and have a debate about it.

Step3 Summary (3min)

(1) 根据板书提供的线索对文中重点知识: ① How has this global warming come about? ② Does it matter? 进行回顾，使学生对整篇科普材料能够有清晰的脉络和全面的理解。 T: Let’s look at the blackboard together. During this lesson, we explored the question how global warming has come about. It’s human activity that has caused the global warming and we learnt different attitudes towards global warming. Dr. Foster thinks it would be a catastrophe and serious, but those scientists like George Hambley are opposed to the view. They believe we should not worry about high levels of carbon dioxide in the air. More carbon dioxide is a positive thing. However, no one knows what effects it will cause.

(2) 设计一个小火车小游戏，让学生先以前后桌四人为一小组，全班有12个小组。每

小组成员根据板书提示，合作提出3-5个问题，让其他组别来挑战。如第一组请第二组来回答，第二组介绍挑战之后，也提出问题，让第三组来挑战回答，以此类推。让全班同学一起动起来。组员合作出题，答题，并对课文内容进行巩固理解；既有写，又有听，还有说，达到多种训练，并活跃了课堂气氛。

T：Let’s play a game called “ Run a Choo- Choo Train” . 4 students a group. Each group writes down 3-5 questions together on the sheet according to the information on the blackboard and the screen. And then ask other groups to challenge. Step4 Assignment

文章结尾提出了一个开放性的问题“Should we do nothing?” .针对这个问题让学生们课后上网等渠道查阅更多全球变暖带来的影响（利或弊）的资料，形成自己的观点, 并对问题展开辩论。 T：Assignment：①Search for some more materials and think about what’s your attitude towards global warming. ② Prepare for the debate about “Should we do something about global warming?” 五、 板书设计

How?

Global warming ← Human activity etra

Higer temperature ↑ ← CO2↑ ← the burning of fossil fuels 小学+初中+高中+努力=大学