从孙维德的办公室向外望去，最多也就是看到层层灰色。孙维德是北京奥组委(Beijing Olympic organising committee)发言人，他并不担心这种情况对明年奥运会的影响。
今年4月，美国能源部下属阿贡国家实验室(Argonne National Laboratory)发布的一项报告称，北京空气质量在20世纪90年代末和21世纪初所获改善，在过去几年中实际上已经丧失。
电力分销商华北电网公司(North China Grid)表示：“我们可能减少对北京地区的电力供应，但具体细节尚未敲定。”
It was the kind of day that can make Beijing summers a trial： a thick， foul-smelling smog sat low over the city， fed by the Chinese capital's rapidly industrialising hinterland and expanding car population.
But though the view from Sun Weide's office was yielding little more than shades of grey， the spokesman for the Beijing Olympic organising committee was unworried about its implications for next year's games.
“The air quality in Beijing has been improving，” Mr Sun declared. “I think the athletes will be happy.”
Others are not so sure. Sports officials from Japan， Australia and the US have expressed concern about the effects of air pollution on athletes. Britain's swimming director said he would delay his team's arrival to the last moment to limit the risk posed by dirty air.
In April， a report issued by the US energy department's Argonne National Laboratory said improvements made to Beijing's air quality in the late 1990s and the 2000s had actually been lost in the past few years.
Mr Sun stresses that Beijing is working on the problem ? though his example of a recent reduction in spring sandstorms will be of little comfort to competitors arriving in August 2008.
With the sheer pace of Chinese development fuelling pollution， the key to meeting Beijing's promise of a “Green Games” will be temporary measures for the event.
The city plans some kind of cut to the number of cars on the roads after a ban on 800，000 official sedans during an international summit last year had a noticeable impact on local air pollution.
Mr Sun also says he expects some factories to reduce or stop production during the games. But officials decline to give details， and companies say they do not know what is expected of them or whether they can expect compensation.
“It's possible that we will reduce electricity supply to the Beijing area， but the details have not yet been decided，” says North China Grid， a power distributor.
The Argonne report says that under some weather conditions， more than half of Beijing's fine particle pollution and 20 to 30 per cent of its ozone comes from neighbouring Hebei province， while nearby Tianjin city and Shandong province also “exert significant influence”.
Even if Beijing cuts man-made emissions to zero， levels of such pollutants could still hit danger levels during the games， it says.
“Because the limit of zero emissions cannot be achieved in practice， and because China is presently undergoing tremendous economic growth， the threat of higher regional emissions and higher concentrations of fine [particulate matter] and ozone by 2008 is very real，” the report says.