Unit 4,Global Warming,energy sources,We depend on energy to do many things in our daily lives. For example, energy lights our cities and heats our buildings. Make a list of things that use energy in your home, in your school, or any other places you can think of.,stove,light,things that use energy in your home,micro-wave oven,cassette player,heating,television,hairdryer,video player,fridge,computer,washing machine,stove,things that use energy in our life,heating,hairdryer,fridge,television,things that use energy in our life,washing machine,electromagnetic oven,electric fan,Do you know how energy is produced? How many sources of energy can you list?,Wind energy is used as power to produce electricity .,Windmills,where electricity is produced by burning coals.,The coal power stations,in which oil is refined and made pure.,The Oil Refineries,a facility designed to convert nuclear energy into electricity.,A nuclear power plant,on the roof of a house on a bright sunny day are used to collect solar energy, making your house warm or heating your water.,Solar panels,are used to keep back water and raise its level for irrigation or for producing electricity, etc.,The Hydro-electric dams,An energy source is “renewable” when supplies of it never run out and “non-renewable” when one day they will run out. Which energy sources on your list are renewable and which are non-renewable?,Discussion,Wind (wind power) Sun (solar energy) Water (hydro-electric power) Plant waste 植物性废物 (biomass energy 生物团能量 ) Hot springs or geysers 间歇泉 (geothermal energy) The sea (tidal energy 潮汐能 ),Renewable,Are they renewable or non-renewable?,wind energy,renewable,solar energy,renewable,hydroelectric power,renewable,geothermal energy,renewable,tidal energy,renewable,biomass energy,renewable,Coal Oil Natural gas Uranium化铀 (nuclear energy),Fossil fuels,Non-renewable,nuclear power plant,non-renewable,an oil refinery(精炼厂),non-renewable,coal power station,non-renewable,natural gas,non-renewable,uranium Ore (铀矿石),non-renewable,What are fossil fuels?,Fossil fuels are Ancient animal and plant material below the surface of the earth with a high carbon content, such as coal, oil and natural gas, which can be burnt to produce energy. They are also known as non-renewable energy because once they are run out of /run out, they cannot be renewed.,1. Have you ever seen a greenhouse?,2. How does the greenhouse work?,The air inside was warm because the glass traps(挡住, 吸收) the heat from the sun and keeps it from escaping(逃跑). This makes the greenhouse heat up(热量 上升) and so the plants can grow throughout(在期间) the cold period.,4. Greenhouse Effect,Global warming,Greenhouse gases trapped the heat from the sun, which causes the temperature of earth goes up.,The Earth Is Becoming Warmer But Does It Matter?,Scanning,What is mainly discussed in the passage? A. What has caused the global warming and whether it matters. B. What effects of the global warming will be. C. How serious the global warming could be. D. What the global warming is.,Reading tips skim the title and Para 1: Title: THE EARTH IS BECOMING WARMER BUT DOES IT MATTER? Para 1: how has this come about and does it matter?,What are the two graphs about?,Graph 1 shows the temperature difference (温度差异) from 1860 to 2000.,Graph 2 shows the carbon dioxide content(二氧化碳含量) in the atmosphere from 1957 to 1997.,Graph 1:,Graph 2:,1) How many paragraphs does the reading text consist of? Please find out the topic sentence of each para.,Read the passage quickly (3),2) Make a division of the text.,Fast-Reading,1. the topic sentences of each paragraph.,Para.1 So how has this come about and does it matter? Para.2 that it is human activity that has caused this global warming rather than a random but natural phenomenon. Para.3 All scientists subscribe to the view that the increase in the earths temperature is due to the burning of fossil fuels like. Para.4 the levels of carbon dioxide have increased greatly over the last 100 to 150 years. Para.5 it is the burning of more and more fossil fuels that has resulted in this increase in carbon dioxide. Para.6 the attitudes of scientists towards this rise are completely different. Para. 7 No one knows the effects of global warming. Does that mean we should do nothing?,agree,led to,happen,Paragraph 1,Paragraphs 2&5,Paragraph 6,2.Main idea of each part,Paragraph 7,How global warming comes about? (全球变暖是怎样产生的),Two different opinions about global warming.,The earth is becoming warmer.,Should we do anything?,How has this come about and does it matter?,Whats the question that has confused us a lot?,Who wrote the magazine article? Whats the name of the magazine?,Sophie Armstrong.,Earth Care.,Reading tips: In English, some nouns begin with a capital letter(大写字母), such as names of people and places, titles(标题) of magazines, newspapers, stories and books, peoples titles(头衔), etc,Part I,global warming,Part II,Para.2 Human activity has caused global war