Unit4
THE EARTH IS BECOMING WARMER-BUT DOES IT MATTER?
全球在变暖——这会带来什么影响吗？
During the 20th century the temperature of the earth rose about one degree Fahrenheit.在20世纪期间，地球温度大约升了华氏1度。That probably does not seem much to you or me, but itis a rapid increase when compared to other natural changes.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。So how has this come about and does it matter?那么，这种温度的增长是怎么产生的呢？会产生什么影响呢？Earth Care’s Sophie Armstrong explores these questions. “关爱地球”组织的索菲·阿姆斯特朗就在探究这些问题。
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.毫无疑问，地球是在变暖，而地球变暖正是人类活动导致而成的，并非是一种无规律的自然现象。
All scientists subscribe to the view that the increase in the earth's temperature is due to the burning of fossil fuels like coal, natural gas andoil to produce energy.所有的科学家赞同这种观点：人们为了生产能量而燃烧化石燃料（如煤、天然气和石油等），从而引起了地球温度的升高。Some by products of this process are called \gases, the most important one of which is carbon dioxide.这个升温的过程的一些副产品就叫做“温室”气体，其中作用重要的就是二氧化碳。Dr Janice Foster explains:\is a natural phenomenon that scientists call the
'greenhouse effect'.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。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.这种现象发生在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，因而使地球变暖的时候。Without the 'greenhouse effect', the earth would be about thirty-three degrees Celsius cooler than itis.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。So, we need those gases.The problem begins when we add huge quantities of extra carbon dioxide into the atmosphere.因此，我们需要这些气体。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。It means that more heat energy tends to be trapped in the atmosphere causing the global temperature to go up.\这意味着更多的热量被困在大气层中，从而引起全球温度上升。”
We know that the levels of carbon dioxide have increased greatly over the last 100 to 150 years. 我们知道，在过去100~150年期间，二氧化碳的含量急剧增加了。 It was a scientist called Charles Keeling, who made accurate measurements of the amount of carbon dioxidein the atmosphere from 1957 to 1997. 有一位名叫查尔斯·基林的科学家曾经把1957~1997年期间大气层中二氧化碳的含量作了精确的统计。 He found that between these years the carbon dioxide in the atmosphere went up from around 315 parts to around 370 parts per million(see Graph 2).他发现，在这些年里，大气层中的二氧化碳含量从315/1000 000上升到370/1000 000。
All scientists accept this data. 所有科学家都接受这个数据。They also agree that it is the burning of more and more fossil fuels that has resulted in this increase in carbon dioxide. 他们还赞同下述观点，正是由于越来越多燃烧化石燃料导致了二氧化碳的增加。 So how high will the temperature increase go? 那么气温会升到多高？ Dr Janice Foster says that over the next 100 years the amount of warming could be as low as 1 to 1.5 degrees Celsius, but it could be as high as 5 degrees.福斯特博士说，在今后的100年里，全球变暖的量可能低到1~1.5摄氏度，但是也有可能高达5摄氏度。 However, the attitude of scientists towards this rise is completely different. 然而，科学家们在对待升温的态度上却是大不相同的。 On the one hand, Dr Fosterthinks that the trend which increases the temperature by 5 degrees would be acatastrophe. 一方面，福斯特博士认为气温升高5度的趋势可能是一场大灾难，She says, \to know what to expect, but it could be very serious.\她说：“对于未来的气候，我们不可能做出精确的预测，但是那时的天气可能是很糟糕的。” Others who agree with her think there may be a rise of several metres in the sea level, 同意她的观点的其他科学家认为，全球变暖会导致海平面上升好几米；or predict severe storms,floods, droughts, famines, the spread of diseases and the disappearance of species. 也有人预言会出现严重的风暴、洪涝、干旱、饥荒、疫病和物种的灭绝。 On the other hand, there are those, like George Hambley, who are opposed to this view, believe that we should not worry about high levels of carbon dioxide in the air. 在另一方面，还有
英语选修六课文翻译
