区域空气质量模拟中查表法的应用研究

在自行开发完善的区域空气质量模式系统RegSRRMS中应用查表法,模拟中国典型城市群对流层大气主要污染物的浓度变化,评估该方法在大气复合污染事件预测和控制中的有效性.首先,利用具有国际先进水平的空气质量模式WRF-CHEM中的化学模块建立了包含完善气相化学、气溶胶过程的箱模式WRFBOX.其次,利用WRFBOX进行化学反应敏感性分析,基于影响污染物的重要因子分别建立了臭氧(O3)及其前体物、无机盐气溶胶和二次有机气溶胶(SOA)查算表数据库,并检验其有效性.最后,将此查算表数据库引入RegSRRMS,建立简化的查表算法.利用直接耦合机制法和查表法对2000年3月珠三角地区污染个例中主要大气污染物浓度进行模拟.通过比较2种方法的模拟结果,显示查表法计算效率提高了57%,能够反映大气光化学反应的非线性特征、气溶胶及其前体物的平衡关系,具有高分辨率、高时效性,能够方便快捷地给出源和受体之间的响应关系,结果可靠.在区域空气质量模式中应用查表法有利于大气污染事件的快速预测以及大气污染控制的快速决策.

Using Look-up Table Method in the Simulation of Regional Atmospheric Environment

Look-up tables of main air pollutants were coupled in our self-developed regional air quality model system RegSRRMS. With the aid of the model, tropospheric air quality over the typical city cluster in China was studied, and the capacity of look-up table method to predict air pollution complex episodes was evaluated. Firstly, based on the state-of-the-art gas phase chemical modules and aerosol modules in WRF-CHEM, a new box model named WRFBOX was built. Secondly, the key physical and chemical factors that may affect tropospheric photochemistry and the formation of aerosols were investigated by using WRFBOX. And then, the look-up tables for photochemical reactions, formation of inorganic aerosols and formation of secondary organic aerosols were constructed by calculating the concentrations of pollutants in various conditions according to these key factors. Finally, the look-up tables were applied in RegSRRMS to simulate concentrations of trace gases and aerosols in Pearl River Delta Region and its surrounding areas during an air pollution complex episode in March 2000. The results showed that the look-up table scheme could not only keep the basic features of atmospheric chemical reactions, but also significantly increase the computational efficiency by saving 57% operation time. Using look-up table scheme in regional air quality models can be propitious to the fast response of air pollution complex in city clusters.