全国各地接二连三地发生了多起特大安全事故，造成严重的人员伤亡，特别是北京密云、吉林商厦等特大安全事故，引起了党中央和国务院的高度关注Unit 4 Global warmingThe greenhouse effect is the rise in temperature that the Earth experiences because certain gases in the atmosphere (大气；大气层) trap energy from the sun. Without these gases， heat would escape back into space and Earths average temperature would be about 60F colder. Because of how they warm our world， these gases are referred to as 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 (面，板) of the greenhouselet in light butkeep heatfromescaping. 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 Earths atmosphere is all around us.It is the air that we breathe. Greenhouse gases in the atmosphere behave much like the glass panes (窗玻璃) in a greenhouse. Sunlight enters the Earths atmosphere， passing through the blanket of greenhouse gases. As it reaches the Earths surface， land， water， and biosphere (生物圈) absorb the sunlights 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.,The greenhouse effect is important. Without the greenhouse effect， the Earth would not be warm enough for humans to live. But if the greenhouse effect becomes stronger， it could make the Earth warmer than usual. Even a little extra warming may cause problems for humans， plants， and animals.Section_Warming Up & Reading PrereadingTHE EARTH IS BECOMING WARMER BUT DOES IT MATTER?During the 20th century the temperature of the earth rose about one degree Fahrenheit. That probably does not seem much to you or me, but it is a rapid increase when compared to other natural changes. So how has this come about and does it matter? EarthCares Sophie Armstrong explores these questions.There is no doubt that the earth is becoming warmer (see Graph 1) and that it is human activity that has caused this global warming rather than a random but natural phenomenon.Fahrenheit/frnhaIt/adj.华氏的n.华氏温度计compared to 与相比when compared to .是“when过去分词”结构，也可看作时间状语从句的省略，补充完整为when it is compared to .。come about 发生；造成，为不及物动词短语。Sophie/sfI/索菲(女名)Armstrong/mstr/阿姆斯特朗(姓)graph/rf/n.图表；坐标图；曲线图random/rndm/adj.胡乱的；任意的phenomenon/fInmInn; US fnmnn/(复数ena/In； n/)n.现象地球在变暖但是这会带来什么影响吗？第12段译文在20世纪期间，地球温度大约上升了1华氏度。这个数值对你我来说很可能是无所谓的，但是跟其他自然变化相比较而言，这却是一种快速的增长。那么，这种温度的增长是怎么产生的呢？会产生什么影响吗？“关爱地球”组织的索菲阿姆斯特朗就在探究这些问题。毫无疑问，地球在变暖(见曲线图一)，而全球变暖正是人类活动导致的，并非一种随意的自然现象。All scientists subscribe to the view that the increase in the earths temperature is due to the burning of fossilfuels like coal, natural gas and oil to produce energy. Some byproducts of this process are called “greenhouse” gases, the most important one of which is carbon dioxide. Dr Janice Foster explains: “There is a natural phenomenon that scientists call the greenhouse effect. This 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. Without the greenhouse effect， the earth would be about thirtythree degrees Celsius cooler than it is. So, we need those gases. The problem begins when we add huge quantities of extra carbon dioxide into the atmosphere. It means that more heat energy tends to be trapped in the atmosphere causing the global temperature to go up.”subscribe to 同意；赞成；订购subscribe/sbskraIb/vi.同意；捐赠；订阅vt.签署(文件)；捐助fossil/fsl/n.化石；从地下采掘出来的(矿物)fuel/fjul/n.燃料that the increase . is due to .是that引导的同位语从句，对the view作进一步的解释和说明。byproduct/baIprdkt/n.副产品the most important one of which .是“代词ofwhich”引导的非限制性定语从句。Janice/dnIs/贾尼丝(女名)Foster/fst/福斯特(姓或男名)that scientists call .是that引导的定语从句，修饰a natural phenomenon, that在从句中作call的宾语。when small amounts of gases至本句末是when引导的表语从句。methane/mieIn/n.甲烷；沼气warm vt.(使)变暖画线部分是without引导的含蓄虚拟条件句。Celsius/selsIs/adj.(温度)摄氏的quantities of 大量的quantity/kwnttI/n.量；数量tend/tend/vi.趋向；易于；照顾 vt.照顾；护理tend to do 倾向于/往往做go up 上升；增长；升起第3段译文,所有的科学家赞同这种观点：人们为了取得能量而燃烧化石燃料(如煤、天然气和石油)，从而引起了地球温度的升高。这个过程(燃烧化石燃料)的一些副产品就叫作“温室”气体，其中最重要的就是二氧化碳。贾尼丝福斯特博士解释说：“有一种科学家称之为温室效应的自然现象。这种现象就是大气层中少量的气体(如二氧化碳、甲烷、水蒸气等)吸收太阳的热量，因而使地球变暖。如果没有这种温室效应，地球的温度将比现在的温度还要低33摄氏度左右。因此，我们需要那些气体。当我们在大气层中增加了大量额外的二氧化碳时，问题就来了。这意味着更多的热量有被困在大气层中的倾向，从而引起全球气温上升。”We know that the levels of carbon dioxide have increased greatly over the last 100 to 150 years. It was a scientist called Charles Keeling， who made accurate measurements of the amount of carbon dioxide in the atmos