A major hub on the Silk Road during China’s Tang dynasty, Urumqi means “beautiful pasture” in the Mongolian language of the Dzungar people. However, since industrialization in the 1990s, a thick haze of sulfurous pollution has engulfed the city. The sulfur dioxide from factories mixes with local anthropogenic aerosol and soil dust, leading Urumqi to become a steadfast member of the top 10 polluted cities in the world. This regional transport, cultural and commercial center of about 3 million inhabitants has airborne particle concentrations consistently 10 times levels the U.S. deems safe. Nevertheless, local authorities claim that the recent introduction of gas-fueled power plants has gone some way toward alleviating the problem.