An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer 2006.Using routinely measured O3 and NOx conce...An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer 2006.Using routinely measured O3 and NOx concentrations,the spatial and temporal variation of O3 and of the total oxidant concentrations was characterized.According to the spatial variability of NO2/NO,the two super sites were found to be representative of polluted urban and downwind suburban conditions.In addition,both sites were located in high O3 regions.In-depth diagnostic of photochemical ozone production processes and their key controlling factors are achieved with an observation-based model(OBM) to gain regional perspectives.Budget analysis and sensitivity model runs show that aldehyde and HONO chemistry had significant impacts on local photochemical ozone production rates.The analysis of calculated Relative Incremental Reactivities shows that photochemical ozone production rates are mainly sensitive to anthropogenic hydrocarbons(HCs) in the polluted urban areas.In the suburban areas,sensitivity to nitrogen oxide(NO) concentrations dominated.Key anthropogenic HCs in both areas are alkenes and aromatics.Significant differences of ozone production efficiencies are identified between the urban and suburban regions,consistent with the OBM diagnosed results.展开更多
基金support from the National Natural Science Foundation of China (Grant No 40675072)National Basic Research Program of China (Grant No 2002CB410801)
文摘An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer 2006.Using routinely measured O3 and NOx concentrations,the spatial and temporal variation of O3 and of the total oxidant concentrations was characterized.According to the spatial variability of NO2/NO,the two super sites were found to be representative of polluted urban and downwind suburban conditions.In addition,both sites were located in high O3 regions.In-depth diagnostic of photochemical ozone production processes and their key controlling factors are achieved with an observation-based model(OBM) to gain regional perspectives.Budget analysis and sensitivity model runs show that aldehyde and HONO chemistry had significant impacts on local photochemical ozone production rates.The analysis of calculated Relative Incremental Reactivities shows that photochemical ozone production rates are mainly sensitive to anthropogenic hydrocarbons(HCs) in the polluted urban areas.In the suburban areas,sensitivity to nitrogen oxide(NO) concentrations dominated.Key anthropogenic HCs in both areas are alkenes and aromatics.Significant differences of ozone production efficiencies are identified between the urban and suburban regions,consistent with the OBM diagnosed results.
