The smog is thinning in China’s eastern cities such as Beijing and Shanghai, but worsening in the country’s interior, according to data collated¹ by environmental group Greenpeace.

根据环保组织绿色和平组织(Greenpeace)整理的数据，北京和上海等中国东部城市的雾霾正在减少，而中国内陆城市的雾霾却在加重。

China’s rich coastal² cities have been cracking down on air pollution for the past three years, setting caps on coal use and closing down nearby coal-fired power plants.

过去三年，中国富裕的沿海城市一直在大力整治空气污染，为煤炭的使用设定上限，并关闭附近的燃煤电厂。

As a result, Beijing’s smog — notorious for blighting³ the capital — has continued its recent run of improvement, with an average concentration PM2.5 fine particle pollution falling 28 per cent year-on-year in the first three months of 2016.

其结果是，在北京，曾以笼罩首都闻名的雾霾延续了近来的好转态势，2016年头三个月PM2.5细颗粒物污染平均浓度同比减少了28%。

Shanghai’s pollution fell 12 per cent, according to figures gathered from city air monitoring stations by Greenpeace.

根据绿色和平组织从城市空气监测站收集的数据，上海市的污染下降了12%。

But in spite of the improvements, both cities recorded average PM2.5 levels of at least six times the World Health Organisation⁴ guideline maximum of 10 microgrammes per cubic metre of air (最/m3).

不过，尽管两个城市的污染状况都有所改善，但它们录得的PM2.5平均水平都至少是世界卫生组织(WHO)建议的最大值每立方米空气10微克的六倍。

Beijing’s annual PM2.5 average is 67.7最/m3, placing it behind the world’s most air-polluted city, New Delhi, which recorded 153 in 2013, the most recent year for which the WHO had data. Hong Kong’s air was at 21, with London on 16.

北京的PM2.5年平均值为每立方米67.7微克，低于全球污染最严重的城市新德里。在世卫组织拥有最新数据的2013年，新德里曾录得每立方米153微克。香港的PM2.5浓度为每立方米21微克，伦敦为每立方米16微克。

“While a country is undergoing economic development, urbanisation and industrialisation, one seldom sees these kind of improvements,” said Chen Jining, minister for environmental protection, speaking at March’s People’s Congress. He added that China was also “being affected⁵ by adverse⁶ weather conditions... such as wind speed decreasing compared to previous years”.

中国环保部部长陈吉宁在今年3月的人代会上曾表示：“我可以坦率告诉大家，在经济社会发展进程之中，在城镇化、工业化进程中取得这样的进步是很少有的。”他还补充说，中国也“受到强厄尔尼诺现象的影响，极端地不利……比如风速与往年相比减少了5%”。

Overall, average PM2.5 levels across 355 Chinese cities surveyed fell 9 per cent compared with the first quarter of last year.

总体上，355个被调查中国城市的平均PM2.5水平比去年第一季度下降了9%。

But although China’s eastern cities are cleaning up their act, it is coming at the expense of the rest of the country. While coal power plants have been shuttered in northern Hebei — a neighbour of Beijing — central and western provinces have seen an increase in coal-plant building “specifically because their air pollution and emissions⁷ regulations are more lax”, said Greenpeace.

不过，尽管中国东部城市正变得清洁，这个成就是以其他城市为代价的。绿色和平组织表示，尽管毗邻北京的河北省关闭了多家燃煤电厂，但中西部省份出现了燃煤电厂建设增加的情况，“尤其是因为那里的空气污染和碳排放监管更宽松”。

Of the cities surveyed, 91 saw air pollution intensify⁸ in the period year-on-year. The worst-affected were in China’s centre and west, of which 69 cities saw air pollution increase an average of more than 20 per cent.

在被调查的城市中，91个城市在过去一年的空气污染同比加重了。受到影响最严重的是中国的中西部，那里的69个城市空气污染平均上升逾20%。