For an idea of what kind of air athletes and spectators can expect during the Olympics -- and what Beijingers can expect for some time to come -- the past week has offered telling indications.
At the start of last week, for the fourth day in a row, emissions made it hard to see down the street, despite the fact the government ordered half the city's cars off the road and closed factories. Officials said they would implement an emergency contingency plan on top of the existing anti-smog measures if pollution lingers closer to the Games.
Twenty-four hours later, the difference was night-and-day: thanks to a series of thunderstorms, triggered in part by the government's arsenal of rainmaking rockets, the following days were dramatically better, like a nice day in New York.
And then, on Monday, following a gasp of fresh air over the weekend, and what some thought was the last of the pollution, Beijing breathed through one of its worst pollution days yet. From the Olympic Green, the city was covered in a veil of white, making it, and even the Bird's Nest stadium, practically vanish.
The vast disparity in pollution levels despite serious efforts to control them says as much about Beijing's general grasp on the country's environmental problems as it does about its last-ditch attempt to banish those problems for the months of the Olympics and Paralympics.
To be sure, the city has made great strides in reducing sources of pollution, from phasing out high emission vehicles to transitioning from coal-fired to electric heat to deploying a fleet of clean natural gas buses. It's also succeeded in getting cars off the roads in the world's grandest anti-pollution experiment, thereby reducing emissions in the city by 20 percent, the government says. To clean up the city for the Olympics, it says it has spent $17.6 billion.
But longer-term and systematic issues have not been addressed. For example, there remains debate over what the source of the pollution problem actually is. Is it the exhaust from all those cars the new middle class is buying? The volatile organic compounds that small factories exhale into the atmosphere? The high emissions of old trucks that have been banned from the city center? Dust and sand from the factories and deserts growing in Inner Mongolia? Straw burning farmers in the suburbs?
Last year, the government launched a long-awaited survey of pollution sources. But like many other orders from the top, the survey will struggle against China's biggest enemies: corruption, government-corporate collusion, and the usual accomplices: censorship and lack of transparency.
Sometimes this means downright doublespeak and falsification. For example, pollution is officially referred to in weather reports not as pollution, wuran, but as wumai, or "fog haze."
Even the question of how polluted the city is has yet to be resolved. Steve Andrews, an environmental consultant who left Beijing last year for fear of reprisal, demonstrated in the Wall Street Journal earlier this year that the government had moved its monitoring stations to low traffic areas to make it look like pollution was decreasing.
He also pointed to the dubious "blue sky day" rating system, which gives that name to any day with an API reading of 100 or lower. Last year, the government beat its blue sky target due to a suspiciously high number of days that were exactly 100. It's made a few people wonder if a teeny bit of pollution readings weren't shaved off the top.
It's also important to remember that the threshold for a "blue sky day" is still 6 times more polluted than the World Health Organization's long-term exposure standard for PM10 particulate matter, at a concentration of 20 micrograms/m3. That means that a "blue sky day" isn't necessarily good for your health, nor does it necessarily mean blue skies at all. To make matters worse, because ozone, a toxic gas, is colorless, a day with clear skies can also be terribly polluted. But that's hard to know, because Beijing doesn't release figures for ozone. It also leaves off the books the smallest type of particulate matter, which is the most dangerous kind for people's lungs.
To clear that up: a "blue sky day" isn't necessarily clean, and can still be heavily polluted. And it doesn't necessarily have blue skies. Also, a day with blue skies can be quite polluted. It's okay, catch your breath.
What's more, officials have insisted, a gray sky doesn't mean a polluted one. "Pictures cannot reflect reality," Du Shaozhong, deputy director of the Beijing municipal bureau of environmental protection, warned recently, in reference to recent media coverage. "Clouds and haze are not pollution. This kind of weather is a natural phenomenon. It has nothing to do with pollution." In case that wasn't clear, he added: "If we were sitting in a bathhouse, there'd be a lot of steam. But no pollution."
To be sure, foreign media have been quick to pounce on Beijing's pollution problem with ugly images that may not tell the whole story. But the haze was pollution. Two days before Du spoke, Beijing was breathing in air with a PM10 concentration of 269 microgram/m3 -- 168% above the WHO standard for short-term exposure.
Mr. Du has thrown up smog screens before. At a press conference a few months ago, I asked why Beijing has lowered, not raised its SO2 standards in recent years, and why it doesn't even release figures for noxious ozone. Du responded that SO2 standards were raised "in accordance with Chinese law." He didn't respond to the question about ozone.
For all of Beijing's emphasis on "analyzing the data scientifically," for all it has spent on temporary improvements, environmental success during the Games will depend on something unscientific that money can't buy: chance. "They better start praying to the Mongolian weather gods," says Ken Rahn, an atmospheric scientist who has worked on solving Beijing's pollution problem. He says that barring long-term solutions like phasing out high pollution factories and reducing coal use, strong winds and rain are the only way to flush out the smog.
In an ironic but typical turn, at a time when the city needs rain, it is also hell bent on preventing it at critical moments, like the opening ceremony. But even though Beijing has an arsenal of rockets full of chemicals to shoot the rain out of clouds before they hit, stopping the rain will also depend on luck. Last year, when the chief engineer of the Beijing Meteorological Bureau was asked what the chances were of banishing rain, he resorted to an unlikely call in secular China: "God bless Beijing," he said.
The simultaneous need for rain and the desire for clear skies seems like a good metaphor for Beijing's struggle with pollution, and its panoply of other problems, in the midst of its intense economic growth. Local governments need to keep the rain from their parade: they want factories to stay afloat, providing jobs, tax revenues and payoffs to officials. But citizens desperately need the rain to wash away the grime: they want to be able to raise their children in a healthy environment, without the threat of those same factories dumping waste into the skies and rivers. And because those same citizens are starting to call for rain more loudly than ever before -- the environment is the second biggest reason for protest in China, following land grabs -- the central government is faced with a conundrum: make rain or keep the smoggy skies dry?
And yet, bringing the rain, or keeping it from falling, is not really in the hands of Beijing. The power of chance in a country so hell-bent on control says a lot about the state of things during the Games and afterwards. Beijing may attempt to take a firm grasp over its image, insisting that smog is fog, or that gray is blue. But it has yet to get a grasp over bigger problems. Including, it seems, just coming clean about what they are.
If they don't, no temporary measures are going to be able to change the pollution. Or the weather, or whatever they want to call it.
A version of this article also appears on the China Beat.