Sep 7, 2014

Using an improved Source Directional Apportionment method to quantify the PM(2.5) source contributions from various directions in a megacity in China

Ying-Ze TianYin-Chang Feng


The transport of particulate matter (PM) and chemical species is an essential mechanism for determining the fate of PM pollutants and their effects. To determine source transport quantitatively, an ambient PM2.5 dataset from a megacity in China was analysed using a novel method called "Source Directional Apportionment" (SDA). The SDA method is developed in this work to quantify contributions of each source category from various directions. The three steps of SDA are (1) to estimate source categories and time series of source contributions to PM with a factor analysis model, (2) to identify directions by trajectory cluster analysis and (3) to quantify source directional contributions for each source category by combining the time series of source contributions to the back trajectories in each direction. For PM2.5 in Chengdu, crustal dust, vehicular exhaust, coal combustion and secondary sulphate are all important contributors to PM; secondary nitrate and cement dust are relatively less influential. Four potential source directions were identified in Chengdu during the sampling period from 2009 to 2011. The percentages of source directional contributions from Directions 1-4 (northeast, southwest to south, southwest and west) were...Continue Reading

Mentioned in this Paper

Sulfates, Inorganic
Engine Exhaust
Air Pollutants, Environmental
Adverse Effects
Particle Size
Hyperbilirubinemia, Neonatal
Factor Analysis, Statistical

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