Mongabay: China's largest city and one of the world's biggest, Shanghai, is set to ban coal burning in just four years, according to a new Clean Air Action Plan. The city-wide ban on coal burning is one effort among many to get Shanghai's infamous smog under control as well as another sign that China has begun to take its pollution problems more seriously. The ban will require the city's 2,500 coal boilers and 300 industrial furnaces to either shut down or shift to cleaner energy by 2015. "The frequency...