Wednesday was a "blue sky day" in the Chinese capital.
But whether that has anything at all to do with the new traffic restrictions that the Beijing government imposed this week seems highly doubtful. There may be less smoke, but there are just as many mirrors when it comes to presenting pollution statistics in China.
A "blue sky day" in official parlance means a day when the Air Pollution Index is below 100, indicating that the air quality is "excellent" or "good." It doesn't necessarily mean you can see the sky, or even the clouds; nor do Chinese definitions of "excellent" and "good" match international ones, but you can't be picky when you live in Beijing.
Anyhow, the Chinese government went to enormous lengths to ensure breathable air during the Beijing Olympics, and foreign visitors were not the only ones impressed. Beijingers, too, were delighted to see how much brighter their city looked when it was not blanketed by smog.
They said so, too, to each other and to journalists and in Internet chat rooms, and the government paid attention.
"We have noticed that domestic and international public opinion has high hopes that by hosting the Olympics Beijing will be built into a livable city," said Du Shaozhong, deputy head of Beijing's Environmental Protection Agency, 10 days into the Olympics. "The temporary measures we have adopted will continue in one way or another," he promised.
This week, the government explained what "one way or another" means. The most notable new rule is the one that keeps 20 percent of Beijing's cars off the streets every day, a plan that resembles measures taken in other cities around the world.
This restriction is not as draconian as the Olympic rule that allowed drivers to use their cars only every other day. Now they are banned only one day a week, depending on their license plate number.
Opinion polls carried out during the Olympics suggested that as many as 80 percent of the city's residents would support this sort of measure. In Internet chat rooms, however, the new rules have drawn nothing but ire.
"We paid full price to buy cars. Why do we have to drive one month less each year only because you say so?" asked one (anonymous) angry car owner on the state-owned CCTV television network's chat room.
Factories in the Beijing area that do not meet pollution standards have not been allowed to reopen, though most industries are working at full speed again after a two month shut-down over the summer.
The air in Beijing has been pretty good for the past month or so, matching the quality we had allowed ourselves to get used to during the Olympic period. It is tempting to think that the combination of the summer restrictions and the new rules on traffic are working.
But Mr. Du himself acknowledged – even as he expressed pride in Beijing's Olympic air performance – that without the strictest rules the capital's air quality "would have been impossible." And keeping such strict rules in place indefinitely would be economically impossible.
So why is the air clear? For the same reason, it turns out, that it was clear last year at this season. In fact even clearer last year, most of the time. We have the autumn winds to thank, not the new traffic regulations.
In 2007, official figures show, even when the streets were choked with traffic and factories all around Beijing were pumping out pollutants at full steam, only two days between Sept. 15th and Oct. 15th were not "blue sky days." This year, five days were not up to scratch over the same period.
Whether the traffic rules will make any difference to the navigability of Beijing's streets we will have to wait and see. The police are being lenient this week, not levying fines on miscreants who drive when they shouldn't.
"I took my car out yesterday when I ought not to have done, and if anyone had stopped me I would just have played stupid," says chauffeur Min Jianjun. "Next week that won't work."