TY - JOUR
T1 - Seasonal variabilities in chemical compounds and acidity of aerosol particles at urban site in the west Pacific
AU - Pan, Xiaole
AU - Uno, Itsushi
AU - Wang, Zhe
AU - Yamamoto, Shigekazu
AU - Hara, Yukari
AU - Wang, Zifa
N1 - Funding Information:
This work was supported by the National Nature Science Foundation of China (Grant No. 41675128 and 41620104008 ) and in part supported by MEXT/JSPS KAKENHI Grant JP25220101 from the Japan Society for the Promotion of Science .
Funding Information:
This work was supported by the National Nature Science Foundation of China (Grant No. 41675128 and 41620104008) and in part supported by MEXT/JSPS KAKENHI Grant JP25220101 from the Japan Society for the Promotion of Science.
Publisher Copyright:
© 2017 The Authors
PY - 2018/6
Y1 - 2018/6
N2 - Mass concentrations of chemical compounds in both PM2.5 (particle aerodynamic diameter, Dp < 2.5 μm) and PM2.5-10 (2.5 < Dp < 10 μm), and acidity of aerosol particles were measured at an urban site in western Japan using a continuous dichotomous Aerosol Chemical Speciation Analyzer (ACSA-12) throughout 2014. Mass concentrations of both PM2.5 and sulfate had distinct seasonal variabilities with maxima in spring and winter, mostly due to long-range transport with the prevailing westerly wind. Mass concentration of nitrate in PM2.5 (fNO3) showed an obvious warm-season-low and cold-season-high pattern as a result of both gas-aerosol phase equilibrium processes under high temperature conditions as well as transport. Nitrate in PM2.5-10 (cNO3) increased during long-range transport of dust, implying the great importance of heterogeneous processes at the surface of coarse mode particles. In this study, Δ[H+] (derived from the difference in pH of extract liquid with/without sampling) was used to indicate the acidity of particles. We found that acidity of particles in PM2.5 (fΔH) was mostly positive with a maximum in August because of the large fraction of nitrate and sulfate. Acidity of particles in PM2.5-10 (cΔH) was negative in winter and spring due to presence of alkaline matter from crustal sources. This study highlights the great importance of anthropogenic pollutants on the acidity of particles in the western Pacific Ocean and further impact on the marine environment and climate. Meteorology and transport played a key role in the allocation of aerosol phase nitrate in PM2.5, PM2.5-10. Seasonal variability of acidity of PM2.5 was mainly attributed to fraction of water-soluble secondary inorganics and source regions.
AB - Mass concentrations of chemical compounds in both PM2.5 (particle aerodynamic diameter, Dp < 2.5 μm) and PM2.5-10 (2.5 < Dp < 10 μm), and acidity of aerosol particles were measured at an urban site in western Japan using a continuous dichotomous Aerosol Chemical Speciation Analyzer (ACSA-12) throughout 2014. Mass concentrations of both PM2.5 and sulfate had distinct seasonal variabilities with maxima in spring and winter, mostly due to long-range transport with the prevailing westerly wind. Mass concentration of nitrate in PM2.5 (fNO3) showed an obvious warm-season-low and cold-season-high pattern as a result of both gas-aerosol phase equilibrium processes under high temperature conditions as well as transport. Nitrate in PM2.5-10 (cNO3) increased during long-range transport of dust, implying the great importance of heterogeneous processes at the surface of coarse mode particles. In this study, Δ[H+] (derived from the difference in pH of extract liquid with/without sampling) was used to indicate the acidity of particles. We found that acidity of particles in PM2.5 (fΔH) was mostly positive with a maximum in August because of the large fraction of nitrate and sulfate. Acidity of particles in PM2.5-10 (cΔH) was negative in winter and spring due to presence of alkaline matter from crustal sources. This study highlights the great importance of anthropogenic pollutants on the acidity of particles in the western Pacific Ocean and further impact on the marine environment and climate. Meteorology and transport played a key role in the allocation of aerosol phase nitrate in PM2.5, PM2.5-10. Seasonal variability of acidity of PM2.5 was mainly attributed to fraction of water-soluble secondary inorganics and source regions.
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U2 - 10.1016/j.envpol.2017.11.089
DO - 10.1016/j.envpol.2017.11.089
M3 - Article
C2 - 29599060
AN - SCOPUS:85044263177
SN - 0269-7491
VL - 237
SP - 868
EP - 877
JO - Environmental Pollution
JF - Environmental Pollution
ER -