成都秋冬季气溶胶散射吸湿增长模型研究

The Model of Aerosol Scattering Hygroscopic Growth During Autumn and Winter in Chengdu

气溶胶散射吸湿增长对大气环境有重要影响,而相关研究在川西地区尚不多见。利用成都市2017年10-12月浊度仪和黑碳仪的逐时观测资料以及同时次的环境气象监测数据〔大气能见度、相对湿度(RH)和NO2质量浓度〕,计算了该区域秋冬季气溶胶散射吸湿增长因子f(RH),进而分析该因子随相对湿度的变化特征。主要结论如下:通过多模型对比,确定了二次多项式是表征研究区秋冬季气溶胶散射吸湿增长的最优模型。基于该最优模型的诊断发现,f(RH)随RH的增加而增大,陡增点出现在RH值为86%~87%时。成都地区f(RH)低于珠三角地区,但总体高于京津冀、长三角地区、巴西和葡萄牙的计算值。

Aerosol scattering hygroscopic growth has an important impact on the atmospheric environment.However,there is little relevant research on the west of Sichuan Province.In this study,the hourly atmospheric observations by nephelometer and aethalometer and the environmental and meteorological datasets of Chengdu from October to December 2017 were used.Based on above dataset which include atmospheric visibility,relative humidity(RH)and NO2 mass concentration.Based on above datasets,the corresponding aerosol scattering hygroscopic growth factor f(RH)was calculated.Furthermore,the variations associated with RH were analyzed.The results show that firstly,quadratic polynomial is determined as the optimal aerosol scattering hygroscopic growth model through the comparisons between multi models;secondly,based on this optimal model,the f(RH)increased with RH,and the sharply increased point appears when the RH reached between 86%and 87%;thirdly,the f(RH)of Chengdu is less than that of Pearl River Delta,but it is generally greater than those of Beijing-Tianjin-Hebei region,Yangtze River Delta,as well as Brazil and Portugal.