Using the global chemistry and transport model MOZART, the simulated distributions of tropospheric hydroxyl free radicals （OH） over China and its sensitivities to global emissions of carbon monoxide （CO）, nitrogen...Using the global chemistry and transport model MOZART, the simulated distributions of tropospheric hydroxyl free radicals （OH） over China and its sensitivities to global emissions of carbon monoxide （CO）, nitrogen oxide （NOx）, and methane （CH4） were investigated in this study. Due to various distributions of OH sources and sinks, the concentrations of tropospheric OH in east China are much greater than in west China. The contribution of NO ＋ perhydroxyl radical （HOs） reaction to OH production in east China is more pronounced than that in west China, and because of the higher reaction activity of non-methane volatile organic compounds （NMVOCs）, the contributions to OH loss by NMVOCs exceed those of CO and take the dominant position in summer. The results of the sensitivity runs show a significant increase of tropospheric OH in east China from 1990 to 2000, and the trend continues. The positive effect of double emissions of NOx on OH is partly offset by the contrary effect of increased CO and CH4 emissions： the double emissions of NOx will cause an increase of OH of 18.1% 30.1%, while the increases of CO and CH4 will cause a decrease of OH of 12.2% 20.8% and 0.3% 3.0%, respectively. In turn, the lifetimes of CH4, CO, and NOx will increase by 0.3%-3.1% with regard to double emissions of CH4, 13.9% 26.3% to double emissions of CO and decrease by 15.3% 23.2% to double emissions of NOx.展开更多
A new method is developed to calculate monthly CO emission data using MOZART modeled and MOPITT observed CO data in 2004. New CO emission data were obtained with budget analysis of the processes controlling CO concent...A new method is developed to calculate monthly CO emission data using MOZART modeled and MOPITT observed CO data in 2004. New CO emission data were obtained with budget analysis of the processes controlling CO concentration such as surface emission, transport, chemical transform and dry deposition. MOPITT data were used to constrain the model simulation. New CO emission data agree well with Horowitz’s emissions in the spatial distributions. Horowitz’s emissions are found to underes- timate CO emissions significantly in the industrial areas of Asia and North America, where high CO emissions are mainly due to the anthropogenic activities. New CO emissions can better reflect the more recent CO actual emissions than Horowitz’s.展开更多
基金supported by the Bureau of Xiamen Science and Technology Research Program(Grant No.3502Z20092020)the Research and Development Special Fund for Public Welfare Industry(Meteorology)(Grant Nos.GYHY200906018and GYHY201006038-03)
文摘Using the global chemistry and transport model MOZART, the simulated distributions of tropospheric hydroxyl free radicals （OH） over China and its sensitivities to global emissions of carbon monoxide （CO）, nitrogen oxide （NOx）, and methane （CH4） were investigated in this study. Due to various distributions of OH sources and sinks, the concentrations of tropospheric OH in east China are much greater than in west China. The contribution of NO ＋ perhydroxyl radical （HOs） reaction to OH production in east China is more pronounced than that in west China, and because of the higher reaction activity of non-methane volatile organic compounds （NMVOCs）, the contributions to OH loss by NMVOCs exceed those of CO and take the dominant position in summer. The results of the sensitivity runs show a significant increase of tropospheric OH in east China from 1990 to 2000, and the trend continues. The positive effect of double emissions of NOx on OH is partly offset by the contrary effect of increased CO and CH4 emissions： the double emissions of NOx will cause an increase of OH of 18.1% 30.1%, while the increases of CO and CH4 will cause a decrease of OH of 12.2% 20.8% and 0.3% 3.0%, respectively. In turn, the lifetimes of CH4, CO, and NOx will increase by 0.3%-3.1% with regard to double emissions of CH4, 13.9% 26.3% to double emissions of CO and decrease by 15.3% 23.2% to double emissions of NOx.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 40575060 and 40318001)
文摘A new method is developed to calculate monthly CO emission data using MOZART modeled and MOPITT observed CO data in 2004. New CO emission data were obtained with budget analysis of the processes controlling CO concentration such as surface emission, transport, chemical transform and dry deposition. MOPITT data were used to constrain the model simulation. New CO emission data agree well with Horowitz’s emissions in the spatial distributions. Horowitz’s emissions are found to underes- timate CO emissions significantly in the industrial areas of Asia and North America, where high CO emissions are mainly due to the anthropogenic activities. New CO emissions can better reflect the more recent CO actual emissions than Horowitz’s.
