耦合气溶胶双参数化方案的大气能见度数值改进算法

将气溶胶复折射率（Aerosol Complex Refractive Index，ACRI）和气溶胶粒径吸湿增长因子（Growth Factor，Gf（RH））参数化方案进行耦合，提出了一种基于Mie散射模型的大气能见度数值改进算法.并利用成都市2017年10~12月WS600一体式气象站、AURORA-3000积分浊度计、AE-31黑碳仪以及GRIMM180环境颗粒物监测仪分别观测获得的相对湿度（RH），干气溶胶散射系数（b_sp），干气溶胶吸收系数（b_sp），气溶胶质量浓度（PM₁₀，PM_2.5，PM₁）及其数浓度粒径分布（Nr（RH）]）的地面逐时观测资料，通过与两种能见度计算模型（经验参数的Mie散射模型和统计模型）在不同能见度区间（<2km，2~5km，5~10km，>10km）模拟结果的对比分析，评估了该改进算法的适用性.结果表明：三种能见度计算方法均能较好地模拟出能见度的变化特征；改进算法通过本地化参数化方案更准确地估计出DACRI和Gf（RH），从而可更准确地模拟出四类能见度区间，对应模拟值与实测值的相关系数（R）分别为0.62，0.90，0.89，0.93，平均相对误差（MRE）分别为9.86%，10.39%，9.94%，14.06%.

An improved numerical algorithm for simulating atmosphere visibility by coupling two aerosol parameterization schemes

Based on the Mie theory, an improved numerical algorithm for simulating atmosphere visibility was proposed by coupling the parameterization schemes of aerosol complex refractive index (DACRI) and aerosol hygroscopic growth factor Gf(RH). By utilizing the monitored data at an hourly time step recorded by WS600 integrated weather station, AURORA-3000 integrating nephelometer, AE-31aethalometer and GRIMM180 environment particle monitors from October to December in 2017 in Chengdu, the applicability of the improved algorithm was futher evaluated by compared with those of two visibility calculation methods, which are Mie theory model with empirical parameters and statistical model, in different visibility intervals (<2km, 2~5km, 5~10km, >10km). The results show that the three visibility calculation methods can capture the variation characteristics of visibility well; The improved algorithm better simulate visibility by adopting localization parameterization schemes to estimate DACRI and Gf(RH). The corresponding correlation coefficients (R) between the simulation and the observation are 0.62, 0.90, 0.89, and 0.93, respectively. The mean relative error (MRE) are 9.86%, 10.39%, 9.94%, and 14.06%, respectively.