2013年中国硫沉降数值模拟研究

Numerical simulation of sulfur deposition in China in 2013

利用CAMx(5.4)空气质量模型模拟分析了2013年中国大陆地区硫沉降的分布、输送特征。结果表明:模拟的SO_24-、SO_2呈现明显的时空分布特征,SO_2浓度冬季最高,SO^(2-)_4浓度夏季最高;SO^(2-)_4、SO_2浓度较高地区主要分布在经济较发达、人为活动较强烈的东部沿海及四川盆地。模拟的中国大陆地区2013年硫沉降总量为7.03×10~6 t,其中湿沉降量占硫沉降总量的62%左右,SO_2的干沉降和SO^(2-)_4湿沉降是硫沉降的主要方式。源追踪技术(PAST)计算结果显示:跨区域传输对重点区域、省(市)的SO_2、SO^(2-)_4有显著贡献;2013年北京、天津、河北SO_2年均浓度受外来源贡献分别占74%、63%、38%,而外来源对北京、天津、河北SO^(2-)_4年均浓度贡献分别为47%、49%、45%。

Distribution and transportation characteristics of sulfur deposition in China in 2013 were analyzed using the Community Multiscale Air Quality Modeling System CAMx（5.4）in this paper.Results showed that simulated distribution of sulfur deposition presented obvious seasonal characteristics;concentration of SO_2 was highest in winter while concentration of SO^（2-）_4was highest in summer.Spatial distribution of SO_2 and SO^（2-）_4were higher in the eastern coast and Sichuan basin where was more developed and contained more man-made activities compared to other districts.Calculated total amount deposition of sulfur was 7.03×106 t in 2013 in mainland of China and wet deposition accounted about 62% of the total sulfur deposition.SO_2 dry deposition and wet deposition of SO^（2-）_4were the main ways to the sulfur deposition.PAST results indicated significant contribution of regional transport to concentrations of SO_2,SO^（2-）_4in key regions and typical cities in Beijing,Tianjin and Hebei area;regional transport contributed to 74%,63%,38% of annual average SO_2 concentration in Beijing,Tianjin and Hebei province while it contributed to 47%,49%,45% respectively of annual average SO^（2-）_4concentration.