Gray skies in Beijing

Photo: melosh

A haze descended on Beijing for four consecutive days earlier this week and made a fitting backdrop for state environmental regulators to announce emergency measures that they’ll put in place if air pollution remains a problem. More power plants and manufacturing facilities could be shut down, and more cars pulled from the roads, according to a news release from the Ministry of Environmental Protection.

This second wave of shut-downs would affect small solvent factories that had previously been overlooked because of their relatively low pollutant emissions as compared to iron factories or coal plants. As The New York Times reports:

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Many smaller factories that use solvents generate volatile organic compounds, commonly referred to as VOCs, which can contribute to ozone and smoggy skies.

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“For Beijing city, a key variable for determining smog levels is VOCs,” said Deborah Seligsohn, China climate program director for the World Resource Institute. “If you cut the car levels without cutting VOCs, you can end up with the problem they’ve faced in the last week. Cutting over 200 factories sounds like the right move.”

Beijing officials report that major air pollutants such as carbon monoxide, carbon dioxide, and particulate matter are generally 20 percent lower this year than in July of last year. However, as The Guardian reported on Monday:

According to the Beijing government, the amount of particulate matter in the air has failed to reach the national benchmark of 100mg a cubic metre for the past four days. [On July 28], it rose to 113, more than double the far tougher ideal standard of 50 set by the World Health Organisation.

Du Shaozhong, vice director of the Beijing Municipal Environmental Protection Bureau, blamed much of the recent air pollution on the weather, citing a rare lack of rain and wind to blow away accumulated emissions. On Tuesday, wind and rain cleared Beijing’s skies and also halved the air pollution index (API) from 90 on Tuesday to 44 on Wednesday. An API above 100 indicates high levels of air pollution, 51-100 is moderate, and 50 and below is considered low in China. However, according to The Week:

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For most of June, pollution in Beijing averaged 87.75 on a government index of 500 — a level that Chinese officials consider safe. But that’s still double the typical levels in most Western cities.

Chinese officials are hoping a storm front will bring relief.