经济学人:空气污染:吹走它(1)

 　　Science and technology: Air pollution: Blown away 科技：空气污染：吹走它

　　Retired 1 jet engines could help clear the smog that smothered 2 big cities. 退役喷射发动机可以用来驱逐笼罩大城市的雾霾。
　　To land at Indira Gandhi Airport is to descend 3 from clear skies to brown ones. 飞机在英迪拉甘地机场着陆的过程中，天空会由明朗转为棕黄。
　　Delhi’s air is toxic 4. 德里的空气是有毒的。
　　According to the World Health Organisation 5, India’s capital has the most polluted atmosphere of all the world’s big cities. 据世界卫生组织报道，印度首都是全世界空气污染最严重的大城市。
　　The government is trying to introduce rules that will curb 6 emissions 7—allowing private cars to be driven only on alternate days, for example,  政府正努力制定控制排放的条例，比如：私家车单双数出行、
　　and enforcing better emissions standards for all vehicles. 强制提高所有车辆的排放标准。
　　But implementing 8 these ideas, even if that can be done successfully, will change things only slowly. 但即使这些方法都能顺利实施，情况也不会立刻好转。
　　A quick fix would help. 速效对策将有所帮助。
　　And Moshe Alamaro, a researcher at the Massachusetts Institute of Technology, thinks he has one. 麻省理工学院的一名研究员Moshe Alamaro有一个速效对策。
　　His idea is to take a jet engine, put it next to one of India’s dirty coal-fired power plants, point its exhaust nozzle at the sky and then switch it on. 他的想法是在印度肮脏的燃煤发电厂的旁边放置一个喷气发动机，将其排气喷嘴对准天空然后开启。
　　His hope is that the jet’s exhaust will disrupt a meteorological phenomenon known as “inversion 9”, in which a layer of warm air settles over cooler air, trapping it,  他希望喷气机的排气能破坏“逆温”这一气象现象（逆温层里暖空气位于冷空气之上，困住冷空气），
　　and that the rising stream of exhaust will carry off the tiny particles of matter that smog is composed of. 上升的排气能带走形成雾霾的细小颗粒物质。
　　Inversion exacerbates 10 air pollution in Delhi and in many other cities, from Los Angeles to Tehran. 逆温加剧了德里市和许多其他城市的空气污染，这些城市从洛杉矶一路到德黑兰。
　　A particularly intense example caused the Great Smog of London in 1952, when four days of air pollution contributed to 12,000 deaths. 最严重的便是1952年伦敦烟雾事件——持续四天的空气污染导致了12000人死亡。
　　Dr Alamaro thinks a jet engine could punch through the inversion layer to create a “virtual chimney” which would carry the trapped pollution above it,  Alamaro博士认为，喷射发动机可以打破逆温层，制造一个“虚拟烟囱”，将被困住的污染物带到逆温层之上，
　　so that it could be dispersed 11 in the wider atmosphere. 这样污染物便可以分散到更广阔的大气层中了。
　　He calculates that all the emissions from a gigawatt coal-fired power plant could be lifted away using a single engine with a nozzle speed of 460 metres a second. 根据他的计算，用一个喷气速度为460米/秒的喷射发动机就可以带走一个千兆瓦燃煤电厂的全部排放量。
　　However, he has not calculated whether a jet engine could disrupt the inversion layer and allow the pollution to escape the city—so he is now going to test that hypothesis. 然而他还没有算出一个喷气发动机是否足以穿透逆温层并把污染物带出城市，所以他现在要验证这一假设。
　　Within eight months, Dr Alamaro plans to put one of his updrafters next to a coal-fired power plant and monitor what happens using a fleet of drones. 在接下来的八个月内，Alamaro博士计划将气流上升装置放在燃煤发电厂旁边并用一队无人机进行监控。
　　He is in discussions with Tata Group, a conglomerate 12 with an electricity-generating arm, to run it next to one of the firm’s power stations. 他正在与塔塔集团（拥有一家发电厂）进行商议，准备在该公司的一家发电站旁进行实验。