Some of the world's most notoriously smoggy cities are hoping for relief in a new plan taking aim at what's coming out of their tailpipes. In response to serious air pollution problems and an attempt to meet emissions standards, China plans to decommission more than 5 million aging vehicles by the end of 2014. 330,000 of the cars being retired will come from Beijing, which sees some 31 percent of its PM2.5 particulate matter coming from vehicle emissions. In all, 20 percent of the vehicles being scrapped will come from Beijing, Tianjin, and the surrounding Hebei province. China also plans to remove up to 5 million additional cars next year.

Exactly how China plans to remove the offending vehicles remains unclear.

China's State Council says that due to failing to keep up with pollution targets, the country now needs to work even harder to cut emissions over the next two years. The problem is quite serious, after all. A big part of this plan is removing the "yellow label" vehicles that don't meet China's fuel standards. Exactly how China plans to remove the offending vehicles remains unclear, but past projects suggest the possibility of offering cash subsidies to some drivers. Previously, Beijing has paid drivers who voluntarily gave up their older vehicles, but the incentives weren't given to owners of the yellow label cars. China has trouble enforcing emissions standards, and Li Kunsheng, an official at the Beijing municipal environmental bureau doesn't see fining drivers as a viable option for solving the pollution problem. It'll be interesting to see how China decides to implement this new plan to get rid of old clunkers. Similar, smaller scrapping plans have been tried before.

In addition to controlling the number of cars on the road and scrapping the worst polluters, China will focus on upgrading fuel quality, closing coal-powered heating systems, updating power stations, steel mills and cement plants, and reducing energy consumption in an attempt to reduce carbon emissions and alleviate its pollution problems.