Chinese cities choke on smog

Beijing issued its highest smog alert of the year on November 29, 2015 after air pollution in Beijing and neighboring regions rose to hazardous levels. On Tuesday, the U.S. Embassy said the Air Quality Index (AQI) stood at levels "beyond index" just as the governments of more than 190 countries are meeting at the 2015 Paris Climate Conference this week in an attempt to forge a new global agreement on climate change.