PM2.5 pollution in sive attention in recent years, Beijing has attracted extensive attention in recent years, but research on the detailed spatiotemporal characteristics of PM2.5 is critically lacking for effective po...PM2.5 pollution in sive attention in recent years, Beijing has attracted extensive attention in recent years, but research on the detailed spatiotemporal characteristics of PM2.5 is critically lacking for effective pollution control. In our study, hourly PM2.5 concentration data of 35 fixed monitoring sites in Beijing were collected continuously from October 2012 to September 2013, for exploring the diurnal and seasonal characteristics of PM2.5 at traffic, urban, and background environments. Spatial trend and regional contribution of PM2.5 under different pollution levels were also investigated. Results show that the average PM2.5 concentration of all the 35 sites （including 5 traffic sites） was 88.6 μg/m^3. Although PM2.5 varied largely with the site location and seasons, a clear spatial trend could be observed with the PM2.5 concentration decreasing linearly from south to north, with a gradient of -0.46 μg/m^3/km for average days, -0.83 μg/m^3/km for heavily-severely polluted days, -0.52μg/m^3/km at lightly-moderately polluted days, and -0.26 μg/m^3/km for excellent-good days. PM2.5 at traffic sites was varied, but was generally over 10 % higher than at the nearby urban assessment sites.展开更多
基金supported by the Key Research Program of Chinese Academy of Sciences (KZZDEW-13)the Gong-Yi Program of Chinese Ministry of Environmental Protection (200909016, 201209008)+1 种基金the National Natural Science Foundation of China (21377127, 41201038)the President Fund of University of Chinese Academy of Sciences (UCAS)
文摘PM2.5 pollution in sive attention in recent years, Beijing has attracted extensive attention in recent years, but research on the detailed spatiotemporal characteristics of PM2.5 is critically lacking for effective pollution control. In our study, hourly PM2.5 concentration data of 35 fixed monitoring sites in Beijing were collected continuously from October 2012 to September 2013, for exploring the diurnal and seasonal characteristics of PM2.5 at traffic, urban, and background environments. Spatial trend and regional contribution of PM2.5 under different pollution levels were also investigated. Results show that the average PM2.5 concentration of all the 35 sites （including 5 traffic sites） was 88.6 μg/m^3. Although PM2.5 varied largely with the site location and seasons, a clear spatial trend could be observed with the PM2.5 concentration decreasing linearly from south to north, with a gradient of -0.46 μg/m^3/km for average days, -0.83 μg/m^3/km for heavily-severely polluted days, -0.52μg/m^3/km at lightly-moderately polluted days, and -0.26 μg/m^3/km for excellent-good days. PM2.5 at traffic sites was varied, but was generally over 10 % higher than at the nearby urban assessment sites.
