中国氨减排对控制PM_(2.5)污染的敏感性研究

Sensitivity analysis of PM_(2.5) pollution to ammonia emission control in China

采用WRF-CMAQ模型,通过研究不同NH_3减排情景下PM_(2.5)年均浓度变化情况,定量分析NH_3减排对控制PM_(2.5)污染的敏感性.模拟结果表明,NH_3减排对全国城市硫酸盐的影响相对较小,但对控制PM_(2.5)及硝酸盐、铵盐的敏感性较强,且随NH_3控制力度增加而敏感度上升,PM_(2.5)及硝酸盐、铵盐年均浓度加速下降.当全国NH_3减排比例分别为20%、40%、60%、80%和100%时,PM_(2.5)对NH_3减排的敏感度分别为0.14、0.16、0.19、0.24和0.30,PM_(2.5)年均浓度下降比例分别为2.7%、6.3%、11.3%、19.0%和29.8%.NH_3减排对PM_(2.5)浓度影响的空间差异性显著,对于河北、河南、湖北、湖南以及成渝等PM_(2.5)污染较重,NH_3排放量大且相对集中的地区,NH_3减排对控制PM_(2.5)污染的效果更加明显.

The air quality modelling system WRF-CMAQ was applied to study the sensitivity of annual PM2.5concentration to NH3emission control with the scenario analysis approach.The results showed reducing NH3emissions would lead to significant drop of PM2.5,nitrate and ammonium concentration,but relatively less impact on sulfate concentration.And annual average concentrations of PM2.5,nitrate,ammonium were estimated to decline faster when emission of NH3are further controlled.The sensitivity of PM2.5to NH3were0.14,0.16,0.19,0.24and0.30,when NH3emission is cut by20%,40%,60%,80%and100%,respectively,and the concentration of PM2.5would decline by2.7%,6.3%,11.3%,19.0%and29.8%thereby.Strong spatial features were observed on the impact of NH3emissions on PM2.5concentration.Control of NH3would promote reducing PM2.5pollution in regions with high NH3emission,such as Hebei,Henan,Hubei and Hunan Province and Chengdu-Chongqing region.