空气污染

　　The big smoke

　　雾都

　　Britain needs to do more to clean up its dirty air

　　英国需要采取更多措施来净化污浊的空气

　　VISITING Oxford Street, a road teeming with tatty shops and overcrowded with people, is plainly a trial. Less plainly, levels of nitrogen dioxide (NO2), a noxious gas, have been found to be around three times higher there than the legal limit. In 2013 the annual mean concentration of NO2 on the street was one of the highest levels found anywhere in Europe.

　　来到牛津街，你会看到街道两边布满了各式杂乱的商店，而道路上人满为患。行走在这条街上，很明显是个磨练。不为人觉察的是，这里有毒气体二氧化氮(NO2)测出含量超出法定水平的约三倍以上。２０１３年，这条街的NO2年均浓度是欧洲最高之一。

　　空气污染.jpg

　　British air is far cleaner than it was a few decades ago. Fewer people use coal-burning stoves; old industrial plants have been decommissioned. But since 2009 levels of nitrogen oxides and particulate matter, coarse or fine particles that are linked to lung cancer and asthma, have fallen more slowly. The exact number of deaths caused by dirty air is unknown. But in 2010 a government advisory group estimated that removing man-made fine particulate matter from the atmosphere would increase life expectancy for those born in 2008 by an average of six months.

　　英国的空气比几十年前干净多了。使用燃煤炉灶的人越来越少；老工业厂已经停产。但自2009年起，氧化氮、微粒物质、以及与肺癌和哮喘相关的粗、细颗粒含量的下降速度减慢了。因污浊空气所引发的死亡人数是未知的。但2010年，一个政府顾问组估算如果将大气中人为造成的微粒物质除去的话，2008年的出生人口人均寿命将增加六个月。

　　Much of the slowdown is the result of fumes from diesel cars, which were championed by successive governments because they use less fuel and thus produce less carbon dioxide than petrol cars. In 2001 only 14% of all cars ran on diesel; by 2013 the proportion had increased to 35%. (Greener “hybrid” and electric cars have increased ninefold since 2006, but account for just 0.5% of the entire fleet.) Second-hand cars are particularly noxious, but even newer ones have not been as clean as hoped. Many cars that belched out few pollutants in tests produced more when on the roads.

　　下降速度放缓的大部分原因在于柴油汽车排放的尾气—这为历任政府所支持，因为柴油汽车耗用更少的能源，比汽油汽车排放更少的二氧化碳。2001年，仅14%的汽车使用柴油。2013年，这个比例上涨到了35%。（更绿色的“混合动力”和电瓶车自2006年以来增加了九倍，但仅占汽车总量的0.5%。）二手汽车尤其有害，但新车也没所期望的那样清洁。很多车在污染物排放测试中排放量低，车在上路时却排放了更多。

　　Government dithering has not helped. Part of the problem is that several departments are responsible for air pollution. This means nobody has taken a lead on it, complains Joan Walley, a Labour MP who chairs an environmental committee that has released a series of damning reports. And few politicians are keen to bash drivers. Talking to Britons about car ownership is “like talking to an American about hand guns”, quips one air-pollution scientist.

　　政府的犹豫不决并没有起到作用。部分问题在于有好几个部门都对空气污染负有责任。这意味着没有人愿意出头，琼·沃利抱怨道，她是一名工党议员，也是一个已发布一系列谴责报告的环境委员会的主席。很少有政客愿意解雇司机。一名空气污染科学界嘲讽说，跟英国人谈论汽车所有权就像“跟美国人谈论手枪一样。”

　　Some improvements have been made. In 2008 a “low-emission zone” was created in London, which targets large vans and coaches. A smaller “ultra low-emission zone” has been proposed for 2020, which would charge all vehicles that are not of a certain standard 12.50 (18.80) a day. European Commission fines for breaching limits may encourage cities to do more. But other countries are more ambitious: 60 such zones exist in Germany, targeting private cars as well as vans. In December Anne Hidalgo, the mayor of Paris, announced that she wanted to ban diesel cars by 2020. Cities in Denmark and the Netherlands do more to boost cycling.

　　成效还是有的。2008年，伦敦设置了一个“低排放区域”，针对的是大卡车和长途公车。已有提案建议在2020年建立一个更小的“超低排放区”，对没达到一定标准的所有车辆一天收费12.5英镑（18.8美元）。欧盟委员会对排烟限制的罚款措施可能促进城市采取进一步的行动。但是其他国家更加具备野心：德国有60个类似的区域，既针对卡车也针对私人汽车。12月，巴黎市长安娜·伊达尔戈宣布她希望在2020年前淘汰柴油汽车。丹麦城市和挪威更侧重于鼓励骑自行车。

　　When a thick “pea souper” smog enveloped London in 1952, causing the deaths of around 4,000 people in one week, the government was compelled to push through legislation to clean the air. Perhaps the largest problem now is that, with rare exceptions such as a Saharan dust smog that covered the capital in April 2014, this new pollution is invisible. But policy-makers should not lose sight of it.

　　当1952年伦敦被浓浓的”淡黄色烟雾”笼罩时，在一周内造成了约4，000人死亡，政府不得不立法来净化空气。也许现在最大的问题是，除了像2014年4月笼罩首都的撒哈拉沙尘烟雾这样的少数情况外，这种新污染是看不见的。但是政策制定者们不能看不见这一点。