TY - JOUR
T1 - Spatial distribution and seasonal variation of char-EC and soot-EC in the atmosphere over China
AU - Han, Y. M.
AU - Lee, S. C.
AU - Cao, J. J.
AU - Ho, K. F.
AU - An, Z. S.
PY - 2009
Y1 - 2009
N2 - A previous study on PM2.5 carbonaceous aerosols measured with the thermal optical reflectance (TOR) method in fourteen Chinese cities is extended by subdividing total EC into char-EC and soot-EC. Average char-EC concentrations show great differences between the fourteen cities and between winter and summer periods, with concentrations of 8.67 and 2.41 μg m-3 in winter and summer, respectively. Meanwhile spatial and seasonal soot-EC variations are small, with average concentrations of 1.26 and 1.21 μg m-3 in winter and summer, respectively. Spatial and temporal distributions of char-EC, similar to EC, are mainly influenced by local fuel consumption, as well as the East Asian monsoon and some meteorological factors such as the mixing height and wet precipitation. The small spatial and seasonal variation of soot-EC is consistent with its regional-to-global dispersion, which may suggest that soot carbon is not local carbon, but regional carbon. Char-EC/soot-EC ratios show summer minimum and winter maximum in all cities, which is in good agreement with the difference in source contributions between the two periods. As OC/EC ratio is affected by the formation of the secondary organic aerosol (SOA), char-EC/soot-EC ratio is a more effective indicator for source identification of carbonaceous aerosol than previously used OC/EC ratio.
AB - A previous study on PM2.5 carbonaceous aerosols measured with the thermal optical reflectance (TOR) method in fourteen Chinese cities is extended by subdividing total EC into char-EC and soot-EC. Average char-EC concentrations show great differences between the fourteen cities and between winter and summer periods, with concentrations of 8.67 and 2.41 μg m-3 in winter and summer, respectively. Meanwhile spatial and seasonal soot-EC variations are small, with average concentrations of 1.26 and 1.21 μg m-3 in winter and summer, respectively. Spatial and temporal distributions of char-EC, similar to EC, are mainly influenced by local fuel consumption, as well as the East Asian monsoon and some meteorological factors such as the mixing height and wet precipitation. The small spatial and seasonal variation of soot-EC is consistent with its regional-to-global dispersion, which may suggest that soot carbon is not local carbon, but regional carbon. Char-EC/soot-EC ratios show summer minimum and winter maximum in all cities, which is in good agreement with the difference in source contributions between the two periods. As OC/EC ratio is affected by the formation of the secondary organic aerosol (SOA), char-EC/soot-EC ratio is a more effective indicator for source identification of carbonaceous aerosol than previously used OC/EC ratio.
KW - Carbonaceous aerosols
KW - Char
KW - China
KW - Soot
KW - Spatial distribution
UR - https://www.scopus.com/pages/publications/71849101407
U2 - 10.1016/j.atmosenv.2009.08.018
DO - 10.1016/j.atmosenv.2009.08.018
M3 - 文章
AN - SCOPUS:71849101407
SN - 1352-2310
VL - 43
SP - 6066
EP - 6073
JO - Atmospheric Environment
JF - Atmospheric Environment
IS - 38
ER -