中国PM2.5跨区域传输特征数值模拟研究

基于CAMx空气质量模型的颗粒物来源追踪技术(PSAT)定量模拟了全国PM2.5及其化学组分的跨区域输送规律,建立了全国31个省市(源)向333个地级城市(受体)的PM2.5及其化学组分传输矩阵.基于此传输矩阵,从区域、省、城市3个空间尺度解析了PM2.5及其主要组分,包括一次PM2.5、硫酸盐、硝酸盐和铵盐的空间来源.结果表明,跨区域传输对重点区域、省及京津冀典型城市的PM2.5污染均有显著贡献,其中京津冀、长江三角洲、珠江三角洲区域及成渝城市群PM2.5年均浓度受区域外省市的贡献分别达到22%、37%、28%、14%;海南、上海、江苏、浙江、吉林、江西等省PM2.5年均浓度受省外源贡献超过45%;北京、天津、石家庄PM2.5年均浓度受省外源影响分别达到37%、42%、33%.

Numerical study on the characteristics of regional transport of PM2.5 in China

In order to study the pattern of regional transport of PM2.5 and its chemical components, we developed a transport matrix of PM2.5 and its chemical components from the 31provinces (source) to 333cities (receptor) by applying the Particulate Source Apportionment Technology (PSAT) of CAMx model. The regional contribution of ambient PM2.5 and its key components, such as primary PM, sulfate, nitrate, and ammonium, are identified and quantified at region, province, and city level. The results indicate significant contribution of regional transport to ambient PM2.5 pollution in key regions and typical cities in Jing-Jin-Ji area. 22%, 37%, 28%, and 14% of ambient PM2.5in Jin-Jing-Ji, Yangtze River Delta, Pearl River Delta, Chengdu-Chongqing area, respectively, is contributed by emissions from outside region. Regional transport of pollutants contributes to more than 45% of annual average PM2.5 concentration in some provinces such as Hainan, Shanghai, Jiangsu, Zhejiang, Jilin and Jiangxi, and contributes to 37%, 42% and 33% of annual average PM2.5 concentration in Beijing, Tianjin, and Shijiazhuang City.