Average concentrations of air particulates in 189 Chinese cities fell by 10 percent in 2015, according to a new Greenpeace report, a sign that pollution overall was decreasing even as catastrophic levels of smog this winter in northern China effectively shut down schools and roads.<br />Overall pollution levels in Beijing were down for the second consecutive year but skyrocketed in December, when a thick gray soup enveloping the capital prompted the government to issue a first-ever "red alert" warning, limiting automobile use and closing schools.<br />The Greenpeace study released Wednesday found the northern Chinese region surrounding Beijing has seen concentrations of microscopic PM2.5 particles drop by a quarter since 2013.<br />Similar improvements were seen in the Yangtze and Pearl river delta areas around Shanghai and Guangzhou.
