Comprehensive assessment of PM2.5 physicochemical properties during the Southeast Asia dry season (southwest monsoon)

• Published in: Journal of geophysical research. Atmospheres Vol. 121; no. 24; pp. 14,589 - 14,611
• Main Authors: Khan, Md Firoz, Sulong, Nor Azura, Latif, Mohd Talib, Nadzir, Mohd Shahrul Mohd, Amil, Norhaniza, Hussain, Dini Fajrina Mohd, Lee, Vernon, Hosaini, Puteri Nurafidah, Shaharom, Suhana, Yusoff, Nur Amira Yasmin Mohd, Hoque, Hossain Mohammed Syedul, Chung, Jing Xiang, Sahani, Mazrura, Mohd Tahir, Norhayati, Juneng, Liew, Maulud, Khairul Nizam Abdul, Abdullah, Sharifah Mastura Syed, Fujii, Yusuke, Tohno, Susumu, Mizohata, Akira
• Format: Journal Article
• Language: English
• Published: Washington Blackwell Publishing Ltd 27-12-2016
• Subjects: Aerosols; Airborne particulates; Atmospheric particulates; Biomass; Biomass burning; Burning; Carbon; chemical compositions; Coal; Coal-fired power plants; Combustion; Correlation analysis; Dry season; Drying; Dust; Dust storms; Earth; Electric power plants; Emissions; Evening; Factorization; Fuels; Geophysics; Identification; Industrial emissions; Industrial plant emissions; Ions; local emission sources; Mathematical models; Meteorology; Morning; Motor vehicles; Nitrogen dioxide; Oil; Organic carbon; Particulate matter; Particulate matter sources; Physicochemical processes; Physicochemical properties; positive matrix factorization; Potassium; Power plants; Properties; Rain; Rare earth elements; Rare species; Salts; Seasons; Secondary aerosols; Southeast Asia dry monsoon; Southwest monsoon; Suspended particulate matter; Traffic engineering; Traffic flow; Trajectories; Vehicle emissions; Vehicles; Water; Southeast Asia
• ISSN: 2169-897X; 2169-8996
• DOI: 10.1002/2016JD025894

A comprehensive assessment of fine particulate matter (PM2.5) compositions during the Southeast Asia dry season is presented. Samples of PM2.5 were collected between 24 June and 14 September 2014 using a high‐volume sampler. Water‐soluble ions, trace species, rare earth elements, and a range of elemental carbon (EC) and organic carbon were analyzed. The characterization and source apportionment of PM2.5 were investigated. The results showed that the 24 h PM2.5 concentration ranged from 6.64 to 68.2 µg m−3. Meteorological driving factors strongly governed the diurnal concentration of aerosol, while the traffic in the morning and evening rush hours coincided with higher levels of CO and NO2. The correlation analysis for non sea‐salt K+‐EC showed that EC is potentially associated with biomass burning events, while the formation of secondary organic carbon had a moderate association with motor vehicle emissions. Positive matrix factorization (PMF) version 5.0 identified the sources of PM2.5: (i) biomass burning coupled with sea salt [I] (7%), (ii) aged sea salt and mixed industrial emissions (5%), (iii) road dust and fuel oil combustion (7%), (iv) coal‐fired combustion (25%), (v) mineral dust (8%), (vi) secondary inorganic aerosol (SIA) coupled with F− (15%), and (vii) motor vehicle emissions coupled with sea salt [II] (24%). Motor vehicle emissions, SIA, and coal‐fired power plant are the predominant sources contributing to PM2.5. The response of the potential source contribution function and Hybrid Single‐Particle Lagrangian Integrated Trajectory backward trajectory model suggest that the outline of source regions were consistent to the sources by PMF 5.0.
Key Points
Physical driving factors govern the concentration of PM2.5
Morning and evening rush hours coincide with enhanced levels of CO and NO2
EC is associated with biomass burning, while OC is mainly due to secondary sources