When Beijing experiences bouts of pollution that blacken the skies and burn the lungs, residents often joke that the Chinese capital needs to build giant fans to clear out the toxic air. Mountains to the north and west help trap smog in the city, and a stiff breeze from Mongolia is the surest way to ensure somewhat cleaner air.
Beijing officials are now considering ways to help that process. Though giant fans are not on the menu, at least not yet, city planners are looking at ways to create corridors that encourage wind flow through the capital. The plan is inspired by research on urban heat islands, which shows that large buildings that block the wind are one of the causes of higher average temperatures in cities as opposed to those in the countryside.
Some critics of the plan say that Beijing, a city of 21 million people, is already so developed — with some suburbs expanding 30 miles or more from the city center — that adding restrictions on future construction will have little effect. They say the persistent air pollution problem will be solved only by controlling emissions from cars, factories, power plants and other sources.
“This isn’t controlling pollution. It’s diverting it,” Wang Bing, a Beijing-based author, wrote on Sina Weibo.
But the plan has received some interest from residents who have grown weary of repeated periods of heavy pollution that is several times in excess of domestic and international air quality standards. Because of rigorous short-term pollution controls, including taking huge numbers of cars off the road each day, Beijing enjoyed relatively clear skies when it hosted the Asia-Pacific Economic Cooperation summit meeting this month. But dangerously poor air quality returned soon after the summit-related restrictions were dropped.
The Beijing Municipal Institute of City Planning and Design is now investigating how limits on building height and location along six corridors may improve air flow in four areas, The Beijing News reported on Friday. Those areas are the central north-south axis through the Drum and Bell Towers, the central business district on the city’s east side, the Shilihe District in the southeast and a west-east corridor running through Qianmen.
Peng Yingdeng, an air pollution expert at the Beijing Municipal Research Institute of Environmental Protection, told the newspaper that the plan would not involve any large-scale demolition or construction, but it was more likely to entail an adjustment of current regulations to limit building heights and densities in specified areas. Similar proposals are under consideration in other major Chinese cities including Hangzhou, Nanjing, Shenyang and Wuhan.
“This kind of work to search for ways to reduce pollution is really worth applauding,” the state-run news agency Xinhua said in a commentary. “If scientists confirm it is effective, then we should promote it on a much larger scale.”
Some experts have expressed doubts that the plan would make a significant difference. Episodes of serious pollution are usually associated with periods of little or no wind, and air corridors do little good if the wind isn’t blowing, Song Guojun, an environmental science professor at Renmin University, told The Beijing News. Solving the air pollution problem ultimately requires controlling pollution sources, he said.
“For most parts of the downtown area, counting on air corridors in the suburbs to reduce pollution levels may not be realistic,” Zhang Zengjie, a researcher from the Beijing Municipal Research Institute of Environmental Protection, told the state-run newspaper China Daily earlier this year.