The continuing smog incidents in China highlight the social effects of relying heavily on coal-fired power generation (in addition to agricultural field burning practices). You can see the scale of pollution in “Beijing’s air pollution as seen from space”, “China enveloped in smog, as seen from space. Again”, “Smog shuts down Harbin, China, as seen from space”. Yale’s e360 blog comments on China’s efforts to rely more on natural gas and less on coal:

Chinese officials have said that to reduce air pollution the most densely populated parts of Beijing should use only gas heat, which limits the supply of natural gas for smaller cities and forces those cities to rely on coal. Pollution levels in Chinese cities commonly exceed World Health Organization guidelines by 40 to 50 times. The problem is most pronounced in northern China, where air pollution from burning coal has already shortened life expectancy by 5.5 years compared to the southern part of the country. China’s natural gas shortage is expected to be 10 percent higher this year than last year, since more users have switched from coal. Authorities are rationing natural gas and prioritizing its use for homes and transportation, but experts don’t expect the shortage to subside anytime soon.

via When, not if, China taps into shale gas | Plugged In, Scientific American Blog Network.