同等学力英语每日一练(-2-28)——学苑教育.pdfVIP

网址： 同等学力英语每日一练（2014-2-28 2014年参加同等学力的考生们，学苑教育献上同等学力英语每日一练，我们将每天发布1--5 道习题，帮助大家夯实基础。大家可随时关注学苑教育同等学力考试频道，我们将第一时间 公布相关考试信息。 Therearehiddenfactorswhich scientistscall “feedbackmechanisms”.No oneknows quitehow theywill interactwith thechangingclimate.Here’soneexample：plants and animals adapt to climate change over centuries.At the current estimate of half a degree centigrade of warming per decade，vegetation （植物 may not keep up. Climatologist James Hansen predicts climate zones will shift toward the poles by 50 to 75 kilometres a year-faster than trees can naturally migrate. Species that findthemselvesinanunfamiliarenvironmentwill die.The 1000kilometre-widestrip of forest running through Canada，the USSR and Scandinavia could be cut by half. Millions of dying treeswould soon lead tomassive forest fires，releasing tons of CO2 and further boosting global warming. Therearedozensofotherpossible “feedbackmechanisms”.Higher temperatureswill fuel condensation and increase cloudiness，which may actually damp down global warming.Others，likethe “albedo”effect，willdotheopposite.The “albedo”effect is the amount of solar energy reflected by the earth’s surface. As northern ice and snow melts and the darker sea and land pokes （戳 through，more heat will be absorbed，adding to the global temperature increase. Even ifwe were tomagically stop all greenhouse-gas emissions tomorrow the impact on global climate would continue for decades. Delay will simply make the problem 1 网址： worse. The fact is that some of us are doing quite well the way things are. In the developed world prosperity has been built on 150 years of cheap fossil fuels. Material progress has been linked to energy consumption. Today 75 percent of all theworld’senergy isconsumedby a quarteroftheworld’spopulation.Theaverage rich wor