On December 8, China News reported that, for the past two months, a serious "haze" has covered nearly half of mainland China. In addition to heavy “foggy” weather in northern China, this haze has spread to Shanghai, Jiangsu, and Zhejiang, and Anhui in East China. Beijing, Tianjin, Hebei, and Shandong were hit once again by heavy haze. According to reports released by the Ministry of Environmental Protection, 104 cities across 20 provinces have been suffering “heavy air pollution.” Experts called for temporary cancellations of all outdoor sports and all outdoor physical education activities. Many freeways were closed due to visibility as low as 30 meters. Some provinces closed almost their entire highway system. The primary pollutant of this round of haze is PM2.5 particles. Shanghai’s PM2.5 pollution indicator reached its record high on December 6. PM2.5 particles are air pollutants with a diameter of 2.5 micrometers or less, small enough to invade even the smallest airway passages. These particles generally come from activities that burn fossil fuels, such as traffic, smelting, and metal processing.
Source: China News, December 8, 2013
http://www.chinanews.com/gn/2013/12-08/5593177.shtml