To realistically simulate the impacts of marine isoprene and primary organic aerosols (POA) on atmospheric chemistry, a unified model framework with online emissions, comprehensive treatment of gas-phase chemistry, an...To realistically simulate the impacts of marine isoprene and primary organic aerosols (POA) on atmospheric chemistry, a unified model framework with online emissions, comprehensive treatment of gas-phase chemistry, and advanced aerosol microphysics is required. In this work, the global-through-urban WRF/Chem model (GU-WRF/Chem) implemented with the online emissions of marine isoprene and size-resolved marine POA is applied to examine such impacts. The net effect of these emissions was increased surface concentrations of isoprene and organic aerosols and decreased surfaced concentrations of hydroxyl radical and ozone over most marine regions. With the inclusion of these emissions, GU-WRF/Chem better predicted the surface concentrations of isoprene and organic aerosols and the aerosol number size distribution when compared to measurements in clean marine conditions.展开更多
Particulate pollution was a critical challenge to the promise of good air quality during the 2008 Beijing Olympic Games,which took place from August 8th to 24th.To ensure good air quality for the Games,several tempora...Particulate pollution was a critical challenge to the promise of good air quality during the 2008 Beijing Olympic Games,which took place from August 8th to 24th.To ensure good air quality for the Games,several temporary emission control measures were implemented in Beijing and surrounding areas.Ambient particulate matter concentration decreased significantly during the Olympic period;however,it is difficult to distinguish the effectiveness of those control measures since meteorology also affects ambient PM_(2.5) concentration.In this work,a multiple linear regression model based on continuous field monitoring at a roadside site was conducted to evaluate the effects of meteorology and emission control measures on the reduction of PM_(2.5) during the 2008 Olympic Games.The hourly data set was divided into two time periods,the no control period,June 22nd to July 4th,and the control period,July 28th to August 21st.The response variable was PM_(2.5) and the meteorology covariates used in the model were hourly temperature,dew point temperature,wind speed and precipitation.Wind direction was not a significant predictor of PM_(2.5) levels in either the control or the no control period.Using the meteorologically-based regression coefficients from the two time periods,meteorology was found to contribute to at least a 16%reduction in PM_(2.5) levels in the roadside microenvironment;while the pollution control measures contributed to at least a 43%reduction in PM_(2.5) levels.展开更多
文摘To realistically simulate the impacts of marine isoprene and primary organic aerosols (POA) on atmospheric chemistry, a unified model framework with online emissions, comprehensive treatment of gas-phase chemistry, and advanced aerosol microphysics is required. In this work, the global-through-urban WRF/Chem model (GU-WRF/Chem) implemented with the online emissions of marine isoprene and size-resolved marine POA is applied to examine such impacts. The net effect of these emissions was increased surface concentrations of isoprene and organic aerosols and decreased surfaced concentrations of hydroxyl radical and ozone over most marine regions. With the inclusion of these emissions, GU-WRF/Chem better predicted the surface concentrations of isoprene and organic aerosols and the aerosol number size distribution when compared to measurements in clean marine conditions.
基金The research described in this paper is supported by the National Natural Science Foundation of China(Grant Nos.50908121 and 20521140077).
文摘Particulate pollution was a critical challenge to the promise of good air quality during the 2008 Beijing Olympic Games,which took place from August 8th to 24th.To ensure good air quality for the Games,several temporary emission control measures were implemented in Beijing and surrounding areas.Ambient particulate matter concentration decreased significantly during the Olympic period;however,it is difficult to distinguish the effectiveness of those control measures since meteorology also affects ambient PM_(2.5) concentration.In this work,a multiple linear regression model based on continuous field monitoring at a roadside site was conducted to evaluate the effects of meteorology and emission control measures on the reduction of PM_(2.5) during the 2008 Olympic Games.The hourly data set was divided into two time periods,the no control period,June 22nd to July 4th,and the control period,July 28th to August 21st.The response variable was PM_(2.5) and the meteorology covariates used in the model were hourly temperature,dew point temperature,wind speed and precipitation.Wind direction was not a significant predictor of PM_(2.5) levels in either the control or the no control period.Using the meteorologically-based regression coefficients from the two time periods,meteorology was found to contribute to at least a 16%reduction in PM_(2.5) levels in the roadside microenvironment;while the pollution control measures contributed to at least a 43%reduction in PM_(2.5) levels.
