大气科学进展(英文版)
大氣科學進展(英文版)
대기과학진전(영문판)
ADVANCES IN ATMOSPHERIC SCIENCES
2010年
3期
705-714
,共10页
杨复沫%Jefrey BROOK%贺克斌%段风魁%马永亮
楊複沫%Jefrey BROOK%賀剋斌%段風魁%馬永亮
양복말%Jefrey BROOK%하극빈%단풍괴%마영량
时空变异%气溶胶%多伦多%大城市%北京%碳
時空變異%氣溶膠%多倫多%大城市%北京%碳
시공변이%기용효%다륜다%대성시%북경%탄
total carbon%PM2.5%temporal variation%carbonaceous aerosol%Beijing%Toronto
Time-series of weekly total carbon (TC) concentrations of fine aerosol particles (PM2.5) in Beijing and Toronto were compared to investigate their respective levels and temporal patterns over two years from August 2001 through July 2003. In addition to this comparison, differences in the factors contributing to the observed concentrations and their temporal variations are discussed. Based upon past knowledge about the two megacities with highly contrasting air pollutant levels, it is not surprising that the average TC concentration in Belling (31.5 μg C m^-3) was greater than that in Toronto by a factor of 8.3. Despite their large concentration differences, in both cities TC comprised a similarly large component of PM2.5. TC concentrations exhibited very different seasonal patterns between the two cities. In Beijing, TC experienced higher levels and greater weekly fluctuations in winter whereas in Toronto this behavior was seen in summer. As a result, the greatest gap in TC concentrations between Beijing and Toronto (by a factor of 12.7) occurred in winter, while the smallest gap (a factor of 4.6) was in summer. In Beijing, seasonal variations in the emissions probably played a greater role than meteorology in influencing the TC seasonality, while in Toronto during the warm months more than 80% of the hourly winds were recorded from the south, along with many potential anthropogenic sources for the days with high TC concentrations. This comparison of the differences provides insight into the major factors affecting carbonaceous aerosol in each city.