Open AccessA study of aerosol properties based on observations of particulate matter from the U.S. Embassy in Beijing, China
Author(s) -
Mukherjee Ado,
Toohey Darin W.
Publication year - 2016
Publication title -
earth's future
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.641
H-Index - 39
ISSN - 2328-4277
DOI - 10.1002/2016ef000367
Subject(s) - particulates , beijing , environmental science , aerosol , atmospheric sciences , air quality index , aerodynamic diameter , visibility , meteorology , china , geography , physics , chemistry , organic chemistry , archaeology
The United States Embassy in Beijing, China publicly released a record of mass concentrations of particulate matter 2.5 µm and smaller in aerodynamic diameter (PM 2.5 ), from April 2008 to the present, measured with a beta attenuation monitor ( BAM ). We compare these measurements with observations of particulate matter recorded at the Beijing Institute of Atmospheric Physics and observations of visibility recorded at the Beijing Capital International Airport ( BCIA ) to assess their value as a record of air quality in the greater Beijing metropolitan area. We find that the PM 2.5 observations correlate well with the other observations of particulate matter ( PM ) over the period 1 January–1 February 2013 using a tapered element oscillating microbalance and an aerosol mass spectrometer ( AMS ), and they exhibit a clear inverse correlation with visibility measured at BCIA . Using inverse visibility as a proxy of radiation extinction, we determine a dry mass extinction efficiency and a dependence of radiation extinction on relative humidity, which is consistent with other studies of polluted urban environments. We deduce a strong degree of homogeneity of particulate pollution across the Beijing metropolitan region and conclude that the U.S. Embassy measurements are a reliable sample of this particulate pollution during periods of photochemical smog. The U.S. Embassy observations of PM 2 .5 appear to remain consistent throughout the available record and can serve as a useful dataset for studying future trends in particulate matter as China implements ambitious measures to improve air quality in the region.