AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Seasonal Variations and Possible Sources of Atmospheric HULIS in Urban Beijing, China
Xinghua Li, Junzan Han, Qing Chang, PHILIP K HOPKE, Beihang University, Beijing China
Abstract Number: 402 Working Group: Urban Aerosols
Abstract Beijing experiences some of the worst particulate air pollution in the world. Thus, understanding the nature of the particulate matter (PM) and its origins is important in the development of effective control strategies. In this study, samples of PM2.5 (particles with aerodynamic diameter less than 2.5 µm) that had been previously analyzed for routine compositional variables (elements, ions, organic and elemental carbon) were further analyzed to measure water-soluble organic compounds (WSOC) and humic-like substance carbon (HULISC). The seasonal variations of the WSOC and HULISC show strong peaks in the winter with lowest concentrations during the summer. There are strong correlations with primary pollutants such as elemental carbon, carbon monoxide, and sulfur dioxide and a weak correlation with ozone. Measurements were made of the emissions of WSOC and HULISC from typical emission sources including a heating stove fueled with wood, corn stover, and coal, as well as light- and heavy-duty vehicles. The relationships among the measured pollutants strongly suggest that there are substantial primary emissions of WSOC and HULISC. Coal combustion in residential stoves is widespread in the region with an estimate of 36 Tg of coal burned per year. The annual emission of HULIS from residential coal burning is estimated to be about 10 Gg with approximately two thirds of this primary HULIS being emitted during the heating season. This study suggests that much of the wintertime OC and sulfate are primary emissions with coal combustion being a major source.