Numerical simulation of extreme air pollution by fine particulate matter in china in winter 2013

In winter 2013, extreme air pollution by fine particulate matter (PM_2.5) in China attracted much public attention. In order to simulate the PM_2.5 pollution, the Community Multiscale Air Quality model driven by the Weather Research and Forecasting model was applied to East Asia in a period from 1 January 2013 to 5 February 2013. The model generally reproduced PM_2.5 concentration in China with emission data in the year 2006. Therefore, the extreme PM_2.5 pollution seems to be mainly attributed to meteorological (weak wind and stable) conditions rather than emission increases in the past several years. The model well simulated temporal and spatial variations in PM_2.5 concentrations in Japan as well as China, indicating that the model well captured characteristics of the PM_2.5 pollutions in both areas on the windward and leeward sides in East Asia in the study period. In addition, contribution rates of four anthropogenic emission sectors (power generation, industrial, residential and transportation) in China to PM_2.5 concentration were estimated by conducting zero-out emission sensitivity runs. Among the four sectors, the residential sector had the highest contribution to PM_2.5 concentration. Therefore, the extreme PM_2.5 pollution may be also attributed to large emissions from combustion for heating in cold regions in China.