选修六unit4Globalwarming概要.pptVIP

【问题导读】 Read the text and try to tell if these sentences are True(T) or False(F)． 1．The greenhouse gases could trap energy from the sun.(　　) 2．Much of the energy reflected by the earth surface is trapped in the atmosphere due to the greenhouse gases.(　　) 答案：1.T　2.T 温室效应又称“花房效应”，自工业革命以来，人类向大气中排放的二氧化碳等吸热性强的温室气体逐年增加，大气的温室效应也随之增强，已引起全球气候变暖等一系列严重问题，引起了全世界各国的关注。 The greenhouse effect is the rise in temperature that the Earth experiences because certain gases in the atmosphere1 (water vapor，carbon dioxide，nitrous oxide，and methane，for example)trap2 energy from the sun.Without these gases，heat would escape back into space and Earth’s average temperature would be about 60°F colder.Because of how they warm our world，these gases are referred to as3 greenhouse gases. Have you ever seen a greenhouse？Most greenhouses look like a small glass house.Greenhouses are used to grow plants，especially in the winter.Greenhouses work by trapping heat from the sun.The glass panels of the greenhouse let in light but keep heat from escaping.This causes the greenhouse to heat up，much like the inside of a car parked in sunlight，and keeps the plants warm enough to live in the winter. The Earth’s atmosphere is all around us.It is the air that we breathe.Greenhouse gases in the atmosphere behave much like the glass panes4 in a greenhouse.Sunlight enters the Earth’s atmosphere，passing through the blanket of greenhouse gases.As it reaches the Earth’s surface，land，water，and biosphere absorb the sunlight’s energy.Once absorbed，this energy is sent back into the atmosphere.Some of the energy passes back into space，but much of it remains trapped in the atmosphere by the greenhouse gases，causing our world to heat up. 【日积月累】 1．atmosphere n．气氛；大气；空气 2．trap vt.诱捕；使……受限制；使……陷入困境 3．be referred to as 被称为 4．pane n．窗格；边；面；窗格玻璃；嵌板 【佳句欣赏】 1．Without these gases，heat would escape back into space and Earth’s average temperature would be about 60°F colder. 如果没有这些温室气体，那么热量会从地球表面散发到太空，地球的平均温度也会降低大约60°F。 此句运用了虚拟语气，“如果没