Source Apportionment of Submicron Particle Size Distribution and PM2.5 Composition during an Asian Dust Storm Period in Two Urban Atmospheres

Abstract

Asian dust storms (ADS), coming from deserts of China and Mongolia, have serious environmental impact on particulate matter (PM) and other pollutants in Taiwan. This study selected two urban sites, Taipei and Kaohsiung, to evaluate the influence of ADS on air quality. During the ADS periods, the hourly PM 10 mass concentrations were 800 µg m -3 in Taipei and the 400 µg m -3 in Kaohsiung, which was three to five times higher than PM episodes during the non-ADS periods. By using the principal component analysis (PCA) manner, the potential sources, the dust storm contained, can be successfully identified during ADS periods. The other potential sources can be identified as vehicular emission and secondary organic aerosols from local area. There have been many studies conducted on the impact of ADS on airborne coarse particle concentration, but very few on fine particle concentration. This study focused on, using PCA for analysis and discussion, the impact of ADS on submicron particle size distribution. The results showed that there was no close relationship between the ADS and Aitken mode (30-100 nm or D 30-100 nm) or accumulation mode (from 0.1-1 µm). However, it was found that strong correlation existed between the ADS and nucleation mode (10-30 nm or D 10-30 nm). In addition, it was found that nucleation mode appeared first, followed by an air plume of dust particles twelve (12) hours later. The nucleation component from the PCA could be used as predictors of arrival time for an ADS. Taking into account the effects of meteorological conditions and employing technique of backward trajectories, PCA can be utilized as a powerful tool to better identify the source of dust storms and provide accurate results.

Application of Positive Matrix Factorization in the Identification of the Sources of PM2.5 in Taipei City

“…Taiwan’s climate and weather are heavily influenced by monsoon; in summer, there is the southwest monsoon, while, in winter, there is the northeast monsoon. Taipei is typically affected by Asian Dust Storms every year from December to May of the following year [ 29 , 30 ]. To minimize influences from sandstorms, this investigation of PM 2.5 pollution sources in the Taipei metropolitan area was conducted in the summer (from 8–30 August 2017), and samples were continuously collected 24 h for a total of 21 days.…”

The Impacts of Taklimakan Dust Events on Chinese Urban Air Quality in 2015

“…In addition, dust aerosols from the arid and semi-arid regions of China and Mongolia could be transported to the east over long distances by the westerly circulation, thus affecting the atmospheric environmental quality in Taiwan, Korea, Japan, and the North Pacific [43][44][45][46]. A recent study also revealed that the mass concentrations of PM 10 in Taipei and Kaohsiung of Taiwan during Asian dust events were 3-5 times those of non-dust days [47]. Zhao et al [48] found that trans-Pacific transport of Asian dust may even affect the ambient PM levels in North America.…”

Characteristics of Respirable Particulate Metals Emitted by a Beehive Firework Display in YanShuei Area of Southern Taiwan

“…Metal species with characteristic values of over 1 in Principal Component Analysis (PCA) (SPSS v.12.0) can be classified into several groups by their sources (Allen et al, 2001;Marcazzan et al, 2001;Manoli et al, 2002;AlMomani, 2003;Azid et al, 2015;Chen et al, 2015;Liang et al, 2015). In each sampling period, the metal species, based on their characteristic values, exhibited three groups in PCA (Table 3).…”