Assessing Beijing's PM _2.5 pollution: severity, weather impact, APEC and winter heating

<jats:p> By learning the PM <jats:sub>2.5</jats:sub> readings and meteorological records from 2010–2015, the severity of PM <jats:sub>2.5</jats:sub> pollution in Beijing is quantified with a set of statistical measures. As PM <jats:sub>2.5</jats:sub> concentration is highly influenced by meteorological conditions, we propose a statistical approach to adjust PM <jats:sub>2.5</jats:sub> concentration with respect to meteorological conditions, which can be used to monitor PM <jats:sub>2.5</jats:sub> pollution in a location. The adjusted monthly averages and percentiles are employed to test if the PM <jats:sub>2.5</jats:sub> levels in Beijing have been lowered since China's State Council set up a pollution reduction target. The results of the testing reveal significant increases, rather than decreases, in the PM <jats:sub>2.5</jats:sub> concentrations in the years 2013 and 2014 as compared with those in year 2012. We conduct analyses on two quasi-experiments—the Asia-Pacific Economic Cooperation meeting in November 2014 and the annual winter heating—to gain insight into the impacts of emissions on PM <jats:sub>2.5</jats:sub> . The analyses lead to a conclusion that a fundamental shift from mainly coal-based energy consumption to much greener alternatives in Beijing and the surrounding North China Plain is the key to solving the PM <jats:sub>2.5</jats:sub> problem in Beijing. </jats:p>