This study reviewed the status of PM2.5 and tropospheric O3 observations in China(15e55N, 72e136E). Initially, the distribution of tropospheric O3 over the globe and China was determined based on satellite observation...This study reviewed the status of PM2.5 and tropospheric O3 observations in China(15e55N, 72e136E). Initially, the distribution of tropospheric O3 over the globe and China was determined based on satellite observations made during 2010e2013. The annual mean values were 29.78 DU and 33.97 DU over the globe and China, respectively. The distribution of PM2.5 and seasonal changes in concentrations in China were then simulated using an aerosol chemistry e climate coupled model system, with an annual mean value of 0.51×10-8kg mà3. The contributions from five different aerosols to the simulated PM2.5 concentrations in different seasons were also determined. The relationships among the emissions of aerosols, greenhouse gases and their precursors and radiative forcings were determined with reference to the(IPCC AR5) Intergovernmental Panel on Climate Change the Fifth Assessment Report. From these relationships, the possible effects of controlling O3 precursors and(PM) particulate matter on the climate were considered. The influence of the control of O3 precursors was not totally clear, and reducing emissions of short-lived greenhouse gases and black carbon was considered a secondary measure for short-term(the next 50years) climate-change mitigation. Reducing emissions of CO2 is still the best strategy for meeting the target of a global average rise in surface air temperature of less than 2C. Near- and short-term emission reduction strategies are important for both effective environmental protection and climate-change mitigation.展开更多
During the period between 18 August and 22 September 2006, an ultraviolet photometric O3 analyzer, a NO-NO2-NOx chemiluminescence analyzer, and a quartz micro-oscillating-scale particle concentration analyzer were sim...During the period between 18 August and 22 September 2006, an ultraviolet photometric O3 analyzer, a NO-NO2-NOx chemiluminescence analyzer, and a quartz micro-oscillating-scale particle concentration analyzer were simultaneously used for monitoring at three different heights each at Beijing （325-m tower） and Tianjin （255-m tower）. These towers belong to the Institute of Atmospheric Physics （IAP） of the Chinese Academy of Sciences （CAS） and to the Tianjin Municipal Meteorological Bureau, respectively. These measurements were used to continuously measure the atmospheric O3 and NOx volume-by-volume concentrations and the PM2.5 mass concentration within a vertical gradient. When combined with meteorological data and information on the variation of vertical characteristics of the various atmospheric pollutants in the two cities, analysis shows that these two cities were seriously polluted by both PM2.5 and O3 during summer and autumn. The highest daily-average concentrations of PM2.5 near the ground in Beijing and Tianjin reached 183 μgm a and 165 μg m^-3, respectively, while the 03 concentrations reached 52 ppb and 77 ppb, and NOx concentrations reached 48 ppb and 62 ppb for these two cities, respectively. The variations in the daily-average concentrations of PM2.5 between Beijing and Tianjin were demonstrated to be consistent over time. The concentrations of PM2.5 measured in Beijing were found to be higher than those in Tianjin. However, the overall O3 concentrations near the ground in Tianjin were higher than in Beijing. NOx concentrations in Tianjin were consistently lower than in Beijing. It was also found that PMz5 pollution in Beijing＇s atmosphere may also be affected by the pollutants originating in and delivered from Tianjin, and that Tianjin was impacted by Beijing＇s pollutants at a significantly reduced level.展开更多
基金funded by the National Basic Research Program of China (2011CB403405)
文摘This study reviewed the status of PM2.5 and tropospheric O3 observations in China(15e55N, 72e136E). Initially, the distribution of tropospheric O3 over the globe and China was determined based on satellite observations made during 2010e2013. The annual mean values were 29.78 DU and 33.97 DU over the globe and China, respectively. The distribution of PM2.5 and seasonal changes in concentrations in China were then simulated using an aerosol chemistry e climate coupled model system, with an annual mean value of 0.51×10-8kg mà3. The contributions from five different aerosols to the simulated PM2.5 concentrations in different seasons were also determined. The relationships among the emissions of aerosols, greenhouse gases and their precursors and radiative forcings were determined with reference to the(IPCC AR5) Intergovernmental Panel on Climate Change the Fifth Assessment Report. From these relationships, the possible effects of controlling O3 precursors and(PM) particulate matter on the climate were considered. The influence of the control of O3 precursors was not totally clear, and reducing emissions of short-lived greenhouse gases and black carbon was considered a secondary measure for short-term(the next 50years) climate-change mitigation. Reducing emissions of CO2 is still the best strategy for meeting the target of a global average rise in surface air temperature of less than 2C. Near- and short-term emission reduction strategies are important for both effective environmental protection and climate-change mitigation.
基金supported by the Beijing Municipal Commission for items including transportation and transformation of air pollutants in Beijing and its neighboring areasBeijing’s air quality objectives research+2 种基金the National Key Basic Research and Development Plan (973 project) (2007CB407303)the grant of the Knowledge Innovation Program of Chinese Academy of Sciences (approved # KZCX1-YW-06-01)the Hi-tech Research and Development Program of China (Grant No.2006AA06A301)
文摘During the period between 18 August and 22 September 2006, an ultraviolet photometric O3 analyzer, a NO-NO2-NOx chemiluminescence analyzer, and a quartz micro-oscillating-scale particle concentration analyzer were simultaneously used for monitoring at three different heights each at Beijing （325-m tower） and Tianjin （255-m tower）. These towers belong to the Institute of Atmospheric Physics （IAP） of the Chinese Academy of Sciences （CAS） and to the Tianjin Municipal Meteorological Bureau, respectively. These measurements were used to continuously measure the atmospheric O3 and NOx volume-by-volume concentrations and the PM2.5 mass concentration within a vertical gradient. When combined with meteorological data and information on the variation of vertical characteristics of the various atmospheric pollutants in the two cities, analysis shows that these two cities were seriously polluted by both PM2.5 and O3 during summer and autumn. The highest daily-average concentrations of PM2.5 near the ground in Beijing and Tianjin reached 183 μgm a and 165 μg m^-3, respectively, while the 03 concentrations reached 52 ppb and 77 ppb, and NOx concentrations reached 48 ppb and 62 ppb for these two cities, respectively. The variations in the daily-average concentrations of PM2.5 between Beijing and Tianjin were demonstrated to be consistent over time. The concentrations of PM2.5 measured in Beijing were found to be higher than those in Tianjin. However, the overall O3 concentrations near the ground in Tianjin were higher than in Beijing. NOx concentrations in Tianjin were consistently lower than in Beijing. It was also found that PMz5 pollution in Beijing＇s atmosphere may also be affected by the pollutants originating in and delivered from Tianjin, and that Tianjin was impacted by Beijing＇s pollutants at a significantly reduced level.
